Synthesis of mononuclear and dinuclear palladium (II) complexes containing oxadithioether ligands and their catalytic activities in norbornene polymerization

Received: 14 May 2021

DOI: 10.1002/aoc.6381

Revised: 1 July 2021

Accepted: 6 July 2021

R E S E A R C H A R T I C L E

Synthesis of mononuclear and dinuclear palladium

(II) complexes containing oxadithioether ligands and their

catalytic activities in norbornene polymerization

Dmitry S. Suslov¹

| Zorikto D. Abramov¹

| Ilya A. Babenko¹

|

Viktor A. Bezborodov¹

Marina V. Pakhomova¹

Gennadii V. Ratovskii¹

| Tatyana N. Borodina²

| Vladimir I. Smirnov²

| Igor A. Ushakov²

| Mikhail V. Bykov¹

| Anastasia V. Suchkova¹

| Alexey I. Vilms¹

|

¹Faculty of Chemistry and Research

Institute of Oil and Coal Chemical

Synthesis, Irkutsk State University, ul.

K. Marksa, 1, Irkutsk, 664003, Russia

²A.E. Favorsky Irkutsk Institute of

Chemistry SB RAS, Favorsky st., 1,

Irkutsk, 664033, Russia

Abstract

The Pd (II) complexes trans-[PdCl₂(μ-L)]₂and [Pd(acac)(L)][BF₄] (L = RS

(CH₂)₂O(CH₂)₂SR, R = Me, Et, ⁿPr, Pr, ⁿBu, Bu, n-hexyl, benzyl) were

obtained through the reaction of Pd(cod)Cl₂or [Pd(acac)(MeCN)₂][BF₄] with

one equivalent of oxadithioether (L). The structural features of these com-

plexes were analyzed by nuclear magnetic resonance (NMR) and Fourier-

transform infrared spectroscopy (FTIR), as well as electrospray ionisation mass

spectrometry and density functional theory calculations. The complexes di-

μ-(2,10-dimethyl-6-oxa-3,9-dithiaundecane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] and (acetylacetonate-κ²O,O⁰)(2,10-dimethyl-6-oxa-3,9-dithiaundecane-κ²S,

S⁰)palladium (II) tetrafluoroborate were characterized by X-ray diffractometry.

The X-ray structures of each complex indicate an axial M–O interaction

formed by the endodentate conformation of the oxadithioether ligand. Palla-

dium (II) dichloride complexes with oxadithioethers were demonstrated to

have a 16-membered dinuclear structure with a trans-configured S₂PdCl₂frag-

ment. In the case of cationic palladium acetylacetonate complexes, only mono-

nuclear complexes with a cis configuration of the oxadithioether fragment

i

Correspondence

D.S. Suslov, Faculty of Chemistry and

Research Institute of Oil and Coal

Chemical Synthesis, Irkutsk State

University, ul. K. Marksa, 1, Irkutsk,

Russia, 664003.

Email: suslov@chem.isu.ru;

suslov.dmitry@gmail.com

Funding information

The reported study was funded by RFBR,

Grant/Award Number: project number

20-33-70139

were observed. Variable temperature H and ¹³C NMR studies of the com-

1

plexes demonstrate dynamic bonding of the oxadithioether ligands consistent

with the presence of diastereoisomers that differ in the orientation of the S-R

groups along with both endodentate and exodentate bonding modes in solu-

tion. FTIR studies of the complexes indicate the presence of isomers in the

solid state. The palladium catalyst precursors trans-[PdCl₂(μ-L)]₂and

[Pd (acac)(L)][BF₄] were found to be active in the addition polymerization of

norbornene. In the presence of cocatalysts, such as diisobutylaluminum chlo-

ride and boron trifluoride etherate, Pd (II) complexes exhibited activities in the

range of 10⁵to 10⁷g of polymer (mol of Pd)^ꢀ1

h

^ꢀ1. The catalyst systems

Appl Organomet Chem. 2021;e6381.

wileyonlinelibrary.com/journal/aoc

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https://doi.org/10.1002/aoc.6381

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SUSLOV ET AL.

showed good thermostability with a high activity of 1.43 ꢁ 10⁷g of polymer

(mol of Pd)^ꢀ1h^ꢀ1at 75^ꢂC. These complexes are examples of Pd (II) complexes

bearing thioether ligands, which are rarely observed in the field of olefin

polymerization.

K E Y W O R D S

acetylacetonate, norbornene, palladium, polymerization, thioethers

1 | INTRODUCTION

polymerization of phenylacetylene,^[40]selective dimeriza-

tion or hydroamination of vinylarenes,^[39,41]and

Transition metal complexes with thioethers as ligands

have been studied intensively for over five decades.^[1–3]

Among these complexes, particular attention has

recently been given to palladium (II) complexes with

sulfur-containing compounds, especially thiacrown

ligands.^[4–14]These compounds have interesting proper-

ties, including the stabilization of rare mononuclear

trivalent oxidation states, C–H bond activation, anion

recognition, photophysical properties, intermolecular π–π

stacking motifs, and axial ligand–metal interactions in

square planar complexes.^{[8,9,15–25]}The last structural

property for Pd (II) complexes are of theoretical interest,

as these complexes may contain a weak bonding

component and serve as important models in associative

mechanisms for ligand substitution reactions in d⁸square

planar complexes.^[8,10]

Sulfur species are poisons for many catalytic pro-

cesses; therefore, sulfur-containing compounds are not

usually employed as ligands in transition metal-catalyzed

reactions. In contrast to phosphorus, sulfur atoms in

thioether ligands have only two substituents, which can

create a less hindered environment.^[3]Nevertheless, the

application of palladium complexes with thioether

ligands as precatalysts for allylic substitution, Suzuki–

Miyaura coupling, and copolymerization of olefins with

carbon monoxide has been reported.^[3,13]Moreover, in

recent years, various organic SNS-, SOS-, and SSS-type

ligands have been shown to be useful in ethylene oligo-

merization catalyst systems based on chromium com-

plexes.^[26–30]In the past decades, palladium (II) catalysts

for olefin (co)polymerization have attracted considerable

attention in both the academic and industrial fields. This

is mainly due to the great tolerance of palladium versus

polar functional groups and their great reactivity toward

polar comonomers.^[31–35]However, Pd (II) complexes

with bidentate oxadithioether ligands as catalysts for

olefin polymerization have only rarely been applied. In

previous research, our group reported the synthesis of

various cationic acetylacetonate palladium complexes,

as well their usage as efficient precursors for the

polymerization of norbornene and its derivatives,^[36–39]

telomerization of butadiene with methanol.^[42]

In this report, we describe the results of the syn-

thesis of novel palladium complexes with SOS-type

ligands trans-[PdCl₂(μ-L)]₂and [Pd(acac)(L)][BF₄]

(L = RS(CH₂)₂O(CH₂)₂SR, R = Me, Et, ⁿPr, ⁱPr, ⁿBu,

ⁱBu, n-hexyl, benzyl). Sixteen new compounds were

fully characterized, and crystal structures of [di-

μ-(2,10-dimethyl-6-oxa-3,9-dithiaundecane-κ²S,S⁰)-bis

[trans-dichloropalladium (II)] and (acetylacetonate-

κ²O,O⁰)(2,10-dimethyl-6-oxa-3,9-dithiaundecane-κ²S,S⁰)

palladium (II) tetrafluoroborate were determined by

X-ray diffraction. Nuclear magnetic resonance (NMR)

and infrared (IR) spectroscopic features of the prepared

complexes are discussed. To examine the influence of

the structural features of trans-[PdCl₂(μ-L)]₂and [Pd

(acac)(L)][BF₄] on their catalytic properties, the addi-

tion polymerization of norbornene with these com-

plexes was also investigated in the presence of

BF₃ꢃOEt₂or AlⁱBu₂Cl.

2 | EXPERIMENTAL SECTION

2.1 | General procedures and materials

All air- and/or moisture-sensitive compounds were

manipulated by using standard high-vacuum line,

Schlenk, or cannula techniques under an argon

atmosphere. Argon (Arnika-Prom-Service) was purified

before feeding to the reactor by passing through

columns packed with oxygen scavenger and molecular

sieve 4A (Aldrich). Diethyl ether, petroleum ether,

and toluene (ZAO Vekton) were distilled from

sodiumꢀbenzophenone. CH₂Cl₂(ZAO Vekton), CH₃CN

(ZAO Vekton), and methanol (ZAO Vekton) were

distilled from CaH₂. Solvents were stored over molecu-

lar sieves. Other chemicals were obtained from Acros

Organic, Sigma-Aldrich, or ABCR and employed with-

out drying or any further purification. All glassware

and steel reactors were dried for at least 3 h in a

150^ꢂC oven and cooled under an argon atmosphere.

SUSLOV ET AL.

3 of 27

Pd(acac)₂was synthesized according to a published

procedure^[43]and recrystallized from acetone. The com-

plexes [Pd(acac)(MeCN)₂]BF₄and Pd(cod)Cl₂were

prepared according to published procedures.^[39,40,44]

5-methoxycarbonylnorbornene was synthesized in stain-

less steel autoclave by the Diels–Alder reactions of

dicyclopentadiene with methyl acrylate (t = 180^ꢂC, 6 h).

The crude products were twice distilled over CaH₂under

argon. The mononomer endo/exoratios were determined

by GC. All other reagents were obtained commercially

and used as received. All NMR spectra were recorded at

room temperature on a Bruker DPX-400 spectrometer. IR

spectra were recorded on a Simex Infralum FT 801

spectrometer. HPLC analyses were performed on a

Thermo-Dionex HPLC system. GC-FID and GC–MS

analyses were performed on Chromatec Crystall 5000.2

(SGE BPX-5 capillary column, benzene internal standard)

and Shimadzu QP2010 Ultra (GSBP-5 MS capillary

column), respectively. TGA/DSC measurements were

performed with a Netzsch STA 449-F3 instrument

with crucibles made of aluminum (sample masses were

in the range of 3–4 mg) at a heating rate of 10 K/min in

nitrogen atmosphere.

L1: Yield: 68%. T_b= 90–92^ꢂC (2 mmHg). ¹H NMR

(400 MHz, CDCl₃, 25^ꢂC): δ 3.65 (t, 4H), 2.68 (t, 4H), 2.14

13

(s, 6H). C{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ 70.35,

33.61, 16.12. IR (liquid film, KBr plates, cm^ꢀ1): 2956

ν_as(C–H from S-CH₃); 2916 ν_as(C–H from S-CH₂and

O-CH₂) and ν_s(C–H from S-CH₃); 2861 ν_s(C–H from

S-CH₂and O-CH₂); 1436 δ_as(C–H from S-CH₃); 1428 δ

(HCH from O-CH₂, scissoring); 1406 δ (HCH from

S-CH₂, scissoring); 1358 δ (CCH from O-CH₂-CH₂,

wagging) with δ (HCH from S-CH₂, scissoring); 1321

δ_s(C–H from S-CH₃); 1288, 1233 δ (CCH from S-CH₂-

CH₂, wagging) with δ (CCH from O-CH₂-CH₂, twisting);

1204, 1193 δ (CCH from S-CH₂-CH₂and O-CH₂-CH₂,

twisting); 1109 ν_as(C–O–C); 1042 ν(C–C–O); 959 ν_s(C–O–

C) and δ(C–H from S–CH₃, rocking, not the main contri-

bution); 857 δ(C–H from S–CH₃, rocking) and skeletal

stretching vibrations; 815, 773, 724 δ(C–H from S-CH₂-

СH₂-O, rocking); 700 ν_as(C–S–C); 660 ν_s(C–S–C).

L2: Yield: 72%. T_b= 80–82^ꢂC (1 mmHg). ¹H NMR

(400 MHz, CDCl₃, 25^ꢂC): δ 3.61 (t, 4H), 2.70 (t, 4H),

2,56 (m, 4H), 1.24 (t, 6H). ¹³C{¹H} NMR (101 MHz,

CDCl₃, 25^ꢂC): δ 70.54, 30.87, 26.26, 14.73. IR (liquid

film, KBr plates, cm^ꢀ1): 2963 ν_as(C–H from CH₃); 2924

ν_as(C–H from S-CH₂and O-CH₂); 2868 ν_s(C–H

from CH₃) and ν_s(C–H from S-CH₂and O-CH₂); 1453

δ_as(C–H from C-CH₃); 1426 δ (HCH from O-CH₂,

scissoring); 1405 δ (HCH from S-CH₂, scissoring); 1374

δ_s(C–H from C-CH₃); 1357 δ (CCH from O-CH₂-C,

wagging) with δ (HCH from S-CH₂, scissoring); 1294 δ

(CCH from S-CH₂-CH₂, wagging) with δ (CCH from

O-CH₂-CH₂, twisting); 1266 δ (CCH from S-CH₂-CH₃,

wagging); 1235 δ (CCH from O-CH₂-CH₂, twisting) with

δ (CCH from S-CH₂-CH₂, wagging); 1203, 1195 δ (CCH

from S-CH₂-CH₂and O-CH₂-CH₂, twisting); 1107

ν_as(C–O–C); 1063 ν(C–C–O); 1043, 1002 ν_s(C–O–C);

974 ν(C–C–S from S-CH₂-CH₃) and δ(C–H from CH₃,

rocking); 783, 754 δ(C–H from S-CH₂-СH₂-O, rocking);

694 ν_as(C–S–C); 656 ν_s(C–S–C).

2.2 | Synthesis of ligands

Attention! These experimental methods for ligand syn-

thesis carry the risk of producing mustard analogs. We

have not studied the biological activity and toxicological

properties of the substances. During the synthesis process

and further use of these compounds, it is necessary to

take appropriate precautions: use personal protective

equipment for hands and respiratory organs, and all

manipulations with these substances should be carried

out in a fume hood. If these substances come in contact

with exposed skin, rinse immediately with plenty of cold

water and seek medical attention.

2.2.1 | General procedure for the synthesis

of 5-oxa-2,8-dithianonane (L1) and 6-oxa-

3,9-dithiaundecane (L2)^[45]

2.2.2 | General procedure for the synthesis

of dithioether ligands L3–L8

To an ethanol (95%) solution of RSH and KOH (molar

ratio 1:1), an equimolar amount of bis(2-chloroethyl)

ether (10% solution in EtOH) was added dropwise for

30 min. The reaction mixture was stirred for 3 h at 80^ꢂC.

The reaction mixture was cooled to 25^ꢂC and later neu-

tralized using H₂SO₄. All volatiles were removed under

reduced pressure. The product was extracted with diethyl

ether (2 ꢁ 50 ml), and the extract was dried over CaCl₂.

The solvent was removed, and the residue was distilled in

a vacuum.

KOH solution in hydrazine hydrate and R₂S₂(molar ratio

KOH:R₂S₂= 5:1) was stirred for 4 h at 90^ꢂC. The reaction

mixture was cooled to 25^ꢂC, and an equimolar amount

of bis(2-chloroethyl) ether was added dropwise. The

resulting mixture was stirred for 2 h at 90^ꢂC. The reaction

product was extracted with diethyl ether (2 ꢁ 50 ml), and

the extract was dried over CaCl₂. The solvent was

removed under reduced pressure. The residue was

distilled in a vacuum.

4 of 27

SUSLOV ET AL.

7-oxa-4,10-dithiatridecane (L3): Yield: 89%. T_b= 119–

ν_as(C–H from CH₃); 2928 ν_as(C–H from СH₂-groups);

2870, 2862 (sh) ν_s(C–H from CH₃) and ν_s(C–H from

СH₂-groups); 1463, 1440 (sh) δ_as(C–H from C-CH₃) and

δ (HCH from CH₂-CH₂-CH₃, scissoring); 1424 δ (HCH

from O-CH₂, scissoring); 1405 δ (HCH from S-CH₂,

scissoring); 1378 δ_s(C–H from C-CH₃); 1357 δ (HCH

from S-CH₂, scissoring) with δ (CCH from O-CH₂-C,

wagging); 1290, 1275 δ (CCH from S-CH₂-CH₂, wag-

ging) with δ (CCH from O-CH₂-CH₂, twisting) and δ

(CCH from CH₂-CH₂-CH₂-CH₃, wagging); 1223 δ (CCH

from CH₂-CH₂-CH₂-CH₃, twisting) and δ (CCH from

O-CH₂-CH₂, twisting) with δ (CCH from S-CH₂-CH₂,

wagging); 1203, 1192 (sh) δ (CCH from S-CH₂-CH₂and

O-CH₂-CH₂, twisting) and δ (CCH from CH₂-CH₂-CH₂-

CH₃, twisting); 1110, 1100 (sh) ν_as(C–O–C); 1055 ν(C–

C–O); 1036, 1014 ν_s(C–O–C); 968 ν(C–C–S from S-CH₂-

CH₂-CH₂-CH₃); 950 (sh) δ(C–H from CH₃, rocking);

914, 877 ν(C–C–C from CH₂-CH₂-CH₂-CH₃); 785, 756,

745, 721 (sh) δ(C–H from СH₂-groups, rocking);

691 ν_as(C–S–C); 661 ν_s(C–S–C).

1

120^ꢂC (1.5 mmHg). H NMR (400 MHz, CDCl₃, 25^ꢂC): δ

3.62 (t, 4H), 2.70 (t, 4H), 2.54 (m, 4H), 1.61 (m, 4H), 0.99

13

(t, 6H). C{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ 70.81,

34.71, 31.50, 23.14, 13.48. IR (liquid film, KBr plates,

cm^ꢀ1): 2960 ν_as(C–H from CH₃); 2927 ν_as(C–H from СH₂-

groups); 2870 ν_s(C–H from CH₃) and ν_s(C–H from СH₂-

groups); 1460 δ_as(C–H from C-CH₃) and δ (HCH from

CH₂-CH₃, scissoring); 1424 δ (HCH from O-CH₂, scissor-

ing); 1406 δ (HCH from S-CH₂, scissoring); 1376 δ_s(C–H

from C-CH₃); 1357 δ (HCH from S-CH₂, scissoring) with

δ (CCH from O-CH₂-C, wagging); 1289 δ (CCH from

S-CH₂-CH₂, wagging) with δ (CCH from O-CH₂-CH₂,

twisting) and δ (CCH from CH₂-CH₂-CH₃, wagging);

1235 δ (CCH from O-CH₂-CH₂, twisting) with δ (CCH

from S-CH₂-CH₂, wagging); 1202, 1190 δ (CCH from S-

CH₂-CH₂and O-CH₂-CH₂, twisting) and δ (CCH from

CH₂-CH₂-CH₃, twisting); 1109, 1100 (sh) ν_as(C–O–C);

1071 (sh), 1054 ν(C–C–O); 1035, 1009 ν_s(C–O–C);

969 (sh) ν(C–C–S from S-CH₂-CH₂-CH₃); 953 δ(C–H from

CH₃, rocking); 896 ν(C–C from CH₂-CH₂-CH₃); 849 (sh),

835 skeletal stretching vibrations; 783, 740, 726 (sh) δ(C–H

from СH₂-groups, rocking); 687 ν_as(C–S–C); 662, 649

ν_s(C–S–C).

2,12-dimethyl-7-oxa-4,10-dithiatridecane (L6): Yield:

1

80%. T_b= 150–153^ꢂC (3.5 mmHg). H NMR (400 MHz,

CDCl₃, 25^ꢂC): δ 3.62 (t, 4H), 2.69 (t, 4H), 2.44 (d, 4H),

1.80 (m, 2H), 0.99 (d, 12H). ¹³C{¹H} NMR (101 MHz,

CDCl₃, 25^ꢂC): δ 70.80, 41.99, 32.15, 28.79, 22.03. IR

(liquid film, KBr plates, cm^ꢀ1): 2956 ν_as(C–H from CH₃);

2926 ν_as(C–H from S-CH₂and O-CH₂) and ν(C–H from

CH); 2869 ν_s(C–H from CH₃) and ν_s(C–H from S-CH₂

and O-CH₂); 1464 δ_as(C–H from C-CH₃); 1428 δ (HCH

from O-CH₂, scissoring); 1418 δ (HCH from S-CH₂in

iBu, scissoring); 1405 (sh) δ (HCH from S-CH₂, scissor-

ing); 1382 and 1365 δ_s(C–H from C-CH₃, doublet); 1365

additional δ (HCH from S-CH₂, scissoring) with δ (CCH

from O-CH₂-C, wagging); 1334 δ(C–H from CH in iBu);

1291 δ (CCH from S-CH₂-CH₂, wagging) with δ (CCH

from O-CH₂-CH₂, twisting); 1247 δ (CCH from O-CH₂-

CH₂, twisting) with δ (CCH from S-CH₂-CH₂, wagging);

1230 (sh) δ (CCH from S-CH₂-CH (CH₃)₂, twisting); 1204,

1191 δ (CCH from S-CH₂-CH₂and O-CH₂-CH₂, twisting);

1168 δ(C–H from CH₃, rocking); 1108 ν_as(C–O–C); 1068

(sh) ν(C–C–O); 1037, 1015 ν_s(C–O–C); 945 ν(C–C–S from

S-CH₂-CH-(CH₃)₂); 922 δ(C–H from CH₃, rocking);

859 ν(C–C–C from CH₂-CH-(CH₃)₂); 805,764, 735, 722

δ(C–H from СH₂-groups, rocking); 694 (sh) ν_as(C–S–C);

675 ν_s(C–S–C).

2,10-dimethyl-6-oxa-3,9-dithiaundecane (L4): Yield:

92%. T_b= 117–119^ꢂC (2 mmHg). ¹H NMR (400 MHz,

CDCl₃, 25^ꢂC): δ 3.62 (t, 4H), 2.73 (t, 4H), 2.97 (m, 2H),

13

1.27 (d, 12H). C{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ

70.91, 35.26, 29.98, 23.52. IR (liquid film, KBr plates,

cm^ꢀ1): 2959 ν_as(C–H from CH₃); 2924 ν_as(C–H from

S-CH₂and O-CH₂); 2896 (sh) ν(C–H from CH); 2866

ν_s(C–H from CH₃) and ν_s(C–H from S-CH₂and O-CH₂);

1460, 1455(sh) δ_as(C–H from C-CH₃); 1427 δ (HCH from

O-CH₂, scissoring); 1405 δ (HCH from S-CH₂, scissoring);

1382 and 1365 δ_s(C–H from C-CH₃, doublet); 1365

additional δ (HCH from S-CH₂, scissoring) with δ (CCH

from O-CH₂-C, wagging); 1291 δ (CCH from S-CH₂-CH₂,

wagging) with δ (CCH from O-CH₂-CH₂, twisting); 1244

δ (CCH from O-CH₂-CH₂, twisting) with δ (CCH from

S-CH₂-CH₂, wagging); 1201, 1191 δ (CCH from S-CH₂-

CH₂and O-CH₂-CH₂, twisting); 1155 δ(C–H from

CH₃, rocking); 1113 (sh), 1103 ν_as(C–O–C); 1055

ν(C–C–O); 1035, 1010 ν_s(C–O–C); 949 (sh) ν(C–C–S

from S-CH-(CH₃)₂); 927 δ(C–H from CH₃, rocking);

882 ν(C–C–C from CH-(CH₃)₂); 768 δ(C–H from СH₂-

groups, rocking); 698 (sh) and 683 ν_as(C–S–C);

645 (sh) and 635 ν_s(C–S–C).

10-oxa-7,13-dithianonadecane (L7): Yield: 90%.

1

T_b= 178–181^ꢂC (1 mmHg). H NMR (400 MHz, CDCl₃,

8-oxa-5,11-dithiapentadecane (L5): Yield: 90%.

25^ꢂC): δ 3.80 (t, 4H), 2.77 (t, 4H), 2.58 (t, 4H), 1.67 (m,

1

T_b= 150–153^ꢂC (2 mmHg). H NMR (400 MHz, CDCl₃,

4H), 1.49 (m, 4H), 1.35 (m, 4H), 1.20 (m, 4H), 0.89 (t,

13

25^ꢂC): δ 3.83 (t, 4H), 2.90 (t, 4H), 2.76 (t, 4H), 1.78

(m, 4H), 1.63 (m, 4H), 1.13 (t, 6H). ¹³C{¹H} NMR

(101 MHz, CDCl₃, 25^ꢂC): δ 71.21, 32.68, 32.30, 31.89,

22.37, 14.13. IR (liquid film, KBr plates, cm^ꢀ1): 2957

6H). C{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ 71.52,

35.59, 34.22, 31.89, 28.31, 24.78, 22.35, 14.05. IR (liquid

film, KBr plates, cm^ꢀ1): 2955 ν_as(C–H from CH₃); 2926

ν_as(C–H from СH₂-groups); 2870 (sh), 2856 ν_s(C–H from

SUSLOV ET AL.

5 of 27

CH₃) and ν_s(C–H from СH₂-groups); 1464, 1441

2.3 | Synthesis of palladium complexes

(sh) δ_as(C–H from C-CH₃) and

δ

(HCH from

SCH₂-(CH₂)₄-CH₃, scissoring); 1424 δ (HCH from O-CH₂,

scissoring); 1405 δ (HCH from S-CH₂, scissoring); 1377

δ_s(C–H from C-CH₃); 1356 δ (HCH from S-CH₂, scissor-

ing) with δ (CCH from O-CH₂-C, wagging); 1287, 1260 δ

(CCH from S-CH₂-CH₂, wagging) with δ (CCH from O-

CH₂-CH₂, twisting) and δ (CCH from SCH₂-(CH₂)₄-CH₃,

wagging); 1240 δ (CCH from SCH₂-(CH₂)₄-CH₃, twist-

ing); 1206, 1190 (sh) δ (CCH from S-CH₂-CH₂and

O-CH₂-CH₂, twisting) and δ (CCH from SCH₂-(CH₂)₄-

CH₃, twisting); 1109 ν_as(C–O–C); 1057 (sh) ν(C–C–O);

1037, 1007 (sh) ν_s(C–O–C); 962 (sh) ν(C–C–S from S-CH₂-

CH₂-(CH₂)₃-CH₃) and δ(C–H from CH₃, rocking);

923, 890, 873, 857 ν(C–C–C from CH₂-(CH₂)₄-CH₃);

804 (sh), 760, 720 δ(C–H from СH₂-groups, rocking);

690 (sh) ν_as(C–S–C); 664 ν_s(C–S–C).

The preparation of di-μ-(5-oxa-2,8-dithianonane-κ²S,S⁰)-

bis[trans-dichloropalladium (II)] (1a) was as follows.

5-Oxa-2,8-dithianonane (115 mg, 0.10 ml, 0.692 mmol)

was dissolved in 10 ml of CH₂Cl₂, and PdCl₂(cod)

(144 mg, 0.500 mmol) was added, forming an orange

solution. The reaction mixture was stirred for 1.5 h at

room temperature. The resulting yellow solution was

concentrated to approximately 3 ml under vacuum. The

addition of diethyl ether (10 ml) resulted in an orange

oily precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to pro-

duce complex 1a as a yellow powder (91 mg, 53%). Anal.

Calcd for C₆H₁₄Cl₂OPdS₂: C, 20.97; H, 4.11; S, 18.66.

Found: C, 20.24; H, 4.58; S, 17.66. Electrospray ionisation

mass spectrometry (ESI-MS) (positive ion mode, MeCN):

m/z 308.92 [M⁺ꢀ Cl]. ¹H NMR (400 MHz, CDCl₃, 25^ꢂC):

δ 4.15 (t, J = 6.3 Hz, 4H, CH₂O), 3.07 (t, J = 6.3 Hz, 4H,

CH₂S), 2.39 (s, 6H, CH₃S). ¹H NMR (400 MHz, DMSO-d₆,

80^ꢂC): δ 3.82 (s, br, 4H, CH₂O), 2.94 (s, br, 4H, CH₂S),

2.29 (s, br, 6H, CH₃S). ¹³C{¹H} NMR (101 MHz, DMSO-

d₆, 80^ꢂC): δ 67.87 (s, CH₂O), 35.54 (s, CH₂S), 17.50 (s,

CH₃S). IR (KBr disk, cm^ꢀ1): 3009, 2986 ν_as(C–H

from S-CH₃); 2919 ν_as(C–H from S-CH₂and O-CH₂) and

ν_s(C–H from S-CH₃); 2888 ν_s(C–H from S-CH₂); 2865

ν_s(C–Hfrom O-CH₂); 1478, 1464 δ_as(C–H from S-CH₃);

1423 δ (HCH from O-CH₂, scissoring); 1407 δ (HCH from

S-CH₂, scissoring); 1357 δ (CCH from O-CH₂-CH₂, wag-

ging) with δ (HCH from S-CH₂, scissoring); 1318 δ_s(C–H

from S-CH₃); 1295, 1284 (sh), 1234 δ (CCH from S-CH₂-

CH₂, wagging) with δ (CCH from O-CH₂-CH₂, twisting);

1202 (sh), 1189 δ (CCH from S-CH₂-CH₂and O-CH₂-

CH₂, twisting); 1125, 1107 (sh) ν_as(C–O–C); 1069, 1057,

1041ν(C–C–O); 964, 950 ν_s(C–O–C); 857 δ(C–H from

S–CH₃, rocking) and skeletal stretching vibra-

tions; 783, 734 δ(C–H from S-CH₂-СH₂-O, rocking);

655 ν_as(C–S–C); 640 ν_s(C–S–C).

5-oxa-1,9-diphenyl-2,8-dithianonane (L8): Yield:

1

89%. H NMR (400 MHz, CDCl₃, 25^ꢂC): δ 7.30–7.22

(m, 10H), 3.73 (s, 4H), 3.51 (t, 4H), 2.57 (t, 4H). ¹³C

{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ 138.32, 128.88,

128.46, 127.00, 70.00, 36.61, 33.23. IR (liquid film, KBr

plates, cm^ꢀ1): 3101 (sh), 3083, 3060, 3027, 3005

(sh) ν(C–H from Ph); 2950 ν_as(C–H from S-CH₂-Ph);

2916 ν_as(C–H from S-CH₂and O-CH₂); 2858 ν_s(C–H

from S-CH₂and O-CH₂) and ν_s(C–H from S-CH₂-Ph);

1601, 1584 ν_as(C=C from Ph); 1493 ν_as(C=C from Ph)

and δ (CCH from Ph); 1472 δ (HCH from S-CH₂-Ph,

scissoring); 1453 δ (CCH from Ph) and ν_as(C=C from

Ph); 1423 δ (HCH from O-CH₂, scissoring); 1404 δ

(HCH from S-CH₂, scissoring); 1357 δ (HCH from

S-CH₂, scissoring) with δ (CCH from O-CH₂-CH₂, wag-

ging) and δ (CCH from S-CH₂-Ph, wagging); 1335

(weak), 1319 δ (CCH from Ph, plane); 1291 δ (CCH

from S-CH₂-CH₂, wagging) with δ (CCH from O-CH₂-

CH₂, twisting); 1239 δ (CCH from S-CH₂-Ph, twisting)

and δ (CCH from S-CH₂-CH₂, twisting); 1200 δ (CCH

from O-CH₂-CH₂and S-CH₂-CH₂, twisting); 1185, 1154,

1146, 917 δ (CCH from Ph, plane); 1108 ν_as(C–O–C);

1073 ν(C–C–O) and δ (CCH from Ph, plane); 1028

ν_s(C–O–C) and δ (CCH from Ph, plane); 1040 (sh),

1018 (sh) ν_s(C–O–C); 1004 (sh) ν_s(C=C from Ph) with

δ (CCH from Ph, plane) and ring deformations; 958 ν

(C_Ar–C–S); 877 ν(C–C–S from S-CH₂-CH₂-O) and skele-

tal stretching vibrations; 845 δ (CCH from Ph, off-

plane); 818, 804 skeletal stretching vibrations and

δ(C–H from S-CH₂-СH₂-O, rocking); 767, 701 δ (CCH

from Ph, off-plane) and δ(C–H from S-CH₂-СH₂-O,

rocking); 676 (sh) ν_as(C–S–C); 655 (sh) ν_s(C–S–C);

620, 564 ring deformations (off-plane).

The preparation of (acetylacetonate-κ²O,O⁰)(5-oxa-

2,8-dithianonane-κ²S,S⁰)palladium (II) tetrafluoroborate

(1b) was as follows. [Pd (acac)(MeCN)₂]BF₄(185 mg,

0.495 mmol) was dissolved in 15 ml of CH₂Cl₂, and

5-oxa-2,8-dithianonane (1 ml of solution (0.495 M),

0.495 mmol) was added to this solution, forming an

orange solution. The reaction mixture was stirred for

1.0 h at room temperature. The resulting orange solution

was concentrated to approximately 3 ml under vacuum.

The addition of diethyl ether (15 ml) resulted in an

orange precipitate, which was collected, washed with

diethyl ether (2 ꢁ 10 ml), and dried (8 h) under vacuum

to produce complex 1b as an orange powder (177 mg,

Further spectroscopic details are given in

Figures S41–S50, S60–S67, and S107–S111 (see electronic

supporting information file, SI).

1

78%). The product contained traces (< 2%) of Et₂O by H

NMR analysis. Anal. Calcd for C₁₁H₂₁BF₄O₃PdS₂: C,

6 of 27

SUSLOV ET AL.

28.81; H, 4.62; S, 13.98. Found: C, 29.02; H, 4.65; S, 14.51.

ESI-MS (positive ion mode, MeCN): m/z 370.99 [M⁺]. ¹H

NMR (400 MHz, CD₃CN, 25^ꢂC): δ 5.67 (s, 0.15H, CH_acac),

5.66 (s, 0.85H, CH_acac), 4.3–3.5 (m, 4H, CH₂O), 3.09 (t, br,

J ≈ 12 Hz, 2H, H^a, CH₂S), 2.84 (d, br, J = 12.9 Hz, 2H,

H^a, CH₂S), 2.4–2.2 (m, 6H, CH₃S), 2.12 (s, 0.9H, CH_3,acac).

2.11 (s, 5.1H, CH_3,acac). ¹³C{¹H} NMR (101 MHz, CD₃CN,

25^ꢂC): δ 187.24 (s, C_CO-acac), 187.21 (s, minor isomer sig-

nal, hereinafter referred to as “minor”), C_CO-acac), 100.96

(s, C_CH-acac), 100.83 (s, minor, C_CH-acac), 66.86 (s, minor,

CH₂O), 66.46(s, CH₂O), 65.33 (s, minor, CH₂O), 39.61(s,

CH₂S), 39.37 (s, minor, CH₂S), 25.70 (s, minor, C_Me-acac),

25.62 (s, C_Me-acac), 18.20 (s, minor, CH₃S), 16.69 (s, minor,

CH₃S), 14.59 (s, CH₃S). IR (film, KBr plate, cm^ꢀ1): 3109

ν(C–H from CH in acac); 3015 ν_as(C–H from S-CH₃);

2931 ν_as(C–H from S-CH₂-СH₂-O), ν_s(C–H from S-CH₃)

and ν_as(C–H from CH₃in acac); 2872 ν_s(C–H from S-

CH₂-СH₂-O); 1561 ν(C=O and C=C in acac); 1521

ν(C=C and C=O in acac); 1475 δ_as(C–H from S-CH₃and

C-CH₃in acac); 1425 δ (HCH from S-CH₂-СH₂-O, scissor-

ing) and δ(C–H from CH in acac, plane); 1369 δ_s(C–H

from C-CH₃in acac) and δ (CCH from O-CH₂-CH₂, wag-

ging) with δ (HCH from S-CH₂, scissoring); 1322 δ_s(C–H

from S-CH₃); 1277 δ (CCH from S-CH₂-CH₂, wagging)

with δ (CCH from O-CH₂-CH₂, twisting); 1243 (sh) acac-

chelate deformations; 1202 δ (CCH from S-CH₂-CH₂and

O-CH₂-CH₂, twisting); 1100 ν_as(B–F) and ν_as(C–O–C);

1056 ν_as(B–F) and ν(C–C–O); 1034 ν_as(B–F) and ν(C–C–

O) and δ(C–H from CH₃in acac, rocking) and acac-

chelate deformations; 974 ν_s(C–O–C); 940 acac-chelate

deformations and ν_as(C–CH₃in acac); 866 δ(C–H from S–

CH₃, rocking) and ν(C–C–S, from S-CH₂-СH₂-O) with

skeletal stretching vibrations; 815 δ(C–H from CH in

acac, off-plane) and δ(C–H from S-CH₂-СH₂-O, rocking);

790 ν_s(B–F) and δ(C–H from S-CH₂-СH₂-O,

rocking); 766, 731 δ(C–H from S-CH₂-СH₂-O, rocking);

694 ν_as(C–S–C); 663 acac-chelate deformations and ν_s(C–

CH₃in acac); 636 ν_s(C–S–C).

The preparation of di-μ-(6-oxa-3,9-dithiaundecane-

κ²S,S⁰)-bis[trans-dichloropalladium (II)] (2a) was as fol-

lows. 6-Oxa-3,9-dithiaundecane (100 mg, 0.10 ml,

0.515 mmol) was dissolved in 5 ml of CH₂Cl₂, and

PdCl₂(cod) (143 mg, 0.502 mmol) was added, forming an

orange solution. The reaction mixture was stirred for 3 h

at room temperature. The resulting orange suspension

was concentrated to approximately 3 ml under vacuum.

The addition of diethyl ether (15 ml) resulted in a yellow

precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to pro-

duce complex 2a as a yellow powder (150 mg, 80%). Anal.

Calcd for C₈H₁₈Cl₂OPdS₂: C, 25.85; H, 4.88; S, 17.25.

Found: C, 25.87; H, 4.87; S, 16.82. ESI-MS (positive ion

mode, MeCN): m/z 336.95 [M⁺ꢀ Cl]. ¹H NMR

(400 MHz, DMSO-d₆, 90^ꢂC): δ 3.76 (s, br, 4H, CH₂O),

2.88 (s, br, 4H, CH₂S), 2.74 (q, br, J = 7.4 Hz, 4H, CH₂S)

1.30 (t, J = 7.3 Hz, 6H, CH₃). ¹³C{¹H} NMR (101 MHz,

DMSO-d₆, 90^ꢂC): δ 69.25 (s, CH₂O), 34.48 (s, br, CH₂S),

29.33 (s, br, CH₂S), 14.18 (s, CH₃). IR (KBr disk, cm^ꢀ1):

2974, 2967 ν_as(C–H from CH₃); 2933 ν_as(C–H from

S-CH₂); 2921 (sh) ν_as(C–H from O-CH₂); 2885 ν_s(C–H

from CH₃); 2866 ν_s(C–H from S-CH₂); 2856 (sh) ν_s(C–H

from O-CH₂); 1465 (sh), 1451 δ_as(C–H from C-CH₃); 1418

δ (HCH from O-CH₂, scissoring) and δ (HCH from S-

CH₂, scissoring); 1377 δ_s(C–H from C-CH₃); 1359 δ (HCH

from S-CH₂, scissoring) with δ (CCH from O-CH₂-C,

wagging); 1291 δ (CCH from S-CH₂-CH₂, wagging) with

δ (CCH from O-CH₂-CH₂, twisting); 1267 δ (CCH from

S-CH₂-CH₃, wagging); 1235 δ (CCH from O-CH₂-CH₂,

twisting) with δ (CCH from S-CH₂-CH₂, wagging); 1202,

1192 δ (CCH from S-CH₂-CH₂and O-CH₂-CH₂, twist-

ing); 1120 ν_as(C–O–C); 1073, 1053 ν(C–C–O); 1023,

1011 ν_s(C–O–C); 974, 963 ν(C–C–S from S-CH₂-CH₃) and

δ(C–H from CH₃, rocking); 860 ν(C–C–S from S-CH₂-

CH₂-O) and skeletal stretching vibrations; 779, 768,

757 δ(C–H from S-CH₂-СH₂-O, rocking); 686 ν_as(C–S–C);

627 ν_s(C–S–C).

The preparation of (acetylacetonate-κ²O,O⁰)(6-oxa-

3,9-dithiaundecane-κ²S,S⁰)palladium

(II) tetrafluoroborate (2b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(140 mg, 0.375 mmol) was dissolved in

19 ml of CH₂Cl₂, and 6-oxa-3,9-dithiaundecane (0.8 ml of

solution (0.470 M), 0.375 mmol) was added, forming an

orange solution. The reaction mixture was stirred for

3.0 h at room temperature. The resulting orange solution

was concentrated to approximately 3 ml under vacuum.

The addition of diethyl ether (15 ml) resulted in an

orange oily precipitate, which was collected, washed with

diethyl ether (2 ꢁ 10 ml), and dried (8 h) under vacuum

to produce complex 2b as an orange oil (162 mg, 89%).

Anal. Calcd for C₁₃H₂₅BF₄O₃PdS₂: C, 32.08; H, 5.18; S,

13.18. Found: C, 31.96; H, 5.21; S, 13.22. ¹H NMR

(400 MHz, CD₃CN, 25^ꢂC): δ 5.71 (s, 0.2H, CH_acac), 5.68

(s, 0.8H, CH_acac), 4.4–3.5 (m, 4H, CH₂O), 3.3–2.9 (m, 4H,

CH₂S), 2.9–2.5 (m, 4H, CH₂S), 2.14 (s, 1.4H, CH_3,acac).

2.12 (s, 4.6H, CH_3,acac), 1.5–1.3 (m, 6H, CH₃). ¹³C{¹H}

NMR (101 MHz, CD₃CN, 25^ꢂC): δ 187.25 (s, C_CO-acac),

187.22 (s, minor, C_CO-acac), 100.78 (s, C_CH-acac), 67.15

(s, CH₂O), 66.65 (s, minor, CH₂O), 38.26 (s, br, CH₂S),

29.99(s, br, CH₂S), 25.72 (s, minor, C_Me-acac), 25.67

(s, C_Me-acac), 12.46 (s, CH₃), 11.86 (s, minor, CH₃). IR

(film, KBr plate, cm^ꢀ1): 3108 ν(C–H from CH in acac);

2971 ν_as(C–H from CH₃); 2934 ν_as(C–H from S-CH₂-СH₂-

O) and ν_as(C–H from CH₃in acac); 2873 ν_s(C–H from

S-CH₂-СH₂-O); 1560 ν(C=O and C=C in acac); 1521

ν(C=C and C=O in acac); 1473 (sh), 1453 δ_as(C–H from

C-CH₃); 1428 δ (HCH from S-CH₂-СH₂-O, scissoring) and

SUSLOV ET AL.

7 of 27

δ(C–H from CH in acac, plane); 1367 δ_s(C–H from

C-CH₃) and δ (CCH from O-CH₂-CH₂, wagging) with δ

(HCH from S-CH₂, scissoring); 1294, 1276 δ (CCH from

S-CH₂-CH₂, wagging) with δ (CCH from O-CH₂-CH₂,

twisting); 1244 (sh) acac-chelate deformations; 1199, 1186

(sh) δ (CCH from S-CH₂-CH₂and O-CH₂-CH₂, twisting);

1101 ν_as(B–F) and ν_as(C–O–C); 1057 ν_as(B–F) and ν(C–C–

O); 1034 ν_as(B–F) and ν_s(C–O–C) and δ(C–H from CH₃in

acac, rocking) and acac-chelate deformations; 980 ν(C–

C–S from S-CH₂-CH₃) and δ(C–H from CH₃, rocking);

940 acac-chelate deformations and ν_as(C–CH₃in acac);

864 ν(C–C–S, from S-CH₂-СH₂-O) and skeletal stretching

vibrations; 817 δ(C–H from CH in acac, off-plane)

and δ(C–H from S-CH₂-СH₂-O, rocking); 782 ν_s(B–F)

and δ(C–H from S-CH₂-СH₂-O, rocking); 733 δ(C–H

from S-CH₂-СH₂-O, rocking); 693 ν_as(C–S–C); 680, 666

acac-chelate deformations and ν_s(C–CH₃in acac);

636 ν_s(C–S–C).

The preparation of di-μ-(7-oxa-4,10-dithiatridecane-

κ²S,S⁰)-bis[trans-dichloropalladium (II)] (3a) was as

follows. 7-Oxa-4,10-dithiatridecane (88 mg, 0.394 mmol)

was dissolved in 11 ml of CH₂Cl₂, and PdCl₂(cod)

(112 mg, 0.392 mmol) was added, forming a yellow sus-

pension. The reaction mixture was stirred for 3 h at room

temperature. The resulting yellow solution was concen-

trated to approximately 2 ml under vacuum. The addition

of diethyl ether (20 ml) resulted in a yellow precipitate,

which was collected, washed with diethyl ether

(2 ꢁ 10 ml), and dried (8 h) under vacuum to produce

complex 3a as a yellow powder (113 mg, 72%). Anal.

Calcd for C₁₀H₂₂Cl₂OPdS₂: C, 30.05; H, 5.55; S, 16.04.

Found: C, 30.86; H, 5.55; S, 15.78. ESI-MS (positive ion

mode, MeCN): m/z 364.98 [M⁺ꢀ Cl]. ¹H NMR

(400 MHz, CDCl₃, 25^ꢂC): δ 4.20 (t, J = 6.6 Hz, 3.2H,

CH₂O), 4.04 (t, J = 6.1 Hz, 0.8H, CH₂O), 3.05 (t, br, over-

lapping, J ≈ 6.0 Hz, 0.9H, CH₂S), 2.99 (t, J = 6.6 Hz,

3.1H, CH₂S), 2.84 (m, br, 4H, CH₂S), 1.80 (h, J = 7.4 Hz,

4H, CH₂), 1.05 (t, J = 7.4 Hz, 6H, CH₃). ¹³C{¹H} NMR

(101 MHz, CDCl₃, 25^ꢂC): δ 69.80 (s, CH₂O), 69.22

(s, minor, CH₂O), 38.78 (s, minor, CH₂S), 38.16 (s, CH₂S),

35.96 (s, minor, CH₂S), 35.61 (s, minor, CH₂S), 21.85

(s, minor, CH₂), 21.51 (s, CH₂), 13.54 (s, minor, CH₃),

13.44 (s, CH₃). IR (KBr disk, cm^ꢀ1): 2964 ν_as(C–H from

CH₃); 2929 ν_as(C–H from СH₂-groups); 2870 ν_s(C–H from

CH₃) and ν_s(C–H from СH₂-groups); 1459 δ_as(C–H from

C-CH₃) and δ (HCH from CH₂-CH₃, scissoring); 1415 δ

(HCH from O-CH₂, scissoring); 1405 δ (HCH from S-

CH₂, scissoring); 1380 δ_s(C–H from C-CH₃); 1360 δ (HCH

from S-CH₂, scissoring) with δ (CCH from O-CH₂-C,

wagging); 1340 δ (CCH from CH₂-CH₂-CH₃, wagging);

1293 δ (CCH from S-CH₂-CH₂, wagging) with δ (CCH

from O-CH₂-CH₂, twisting) and δ (CCH from CH₂-CH₂-

CH₃, wagging); 1240 δ (CCH from O-CH₂-CH₂, twisting)

with δ (CCH from S-CH₂-CH₂, wagging) and δ (CCH

from CH₂-CH₂-CH₃, twisting); 1202, 1184 δ (CCH

from S-CH₂-CH₂and O-CH₂-CH₂, twisting) and δ

(CCH from CH₂-CH₂-CH₃, twisting); 1112, 1098

(sh) ν_as(C–O–C); 1078 (sh), 1061 ν(C–C–O); 1040, 1021

ν_s(C–O–C); 985 ν(C–C–S from S-CH₂-CH₂-CH₃);

964 δ(C–H from CH₃, rocking); 901 ν(C–C from CH₂-

CH₂-CH₃); 859 ν(C–C–S from S-CH₂-CH₂-O) and skeletal

stretching vibrations; 787, 739 δ(C–H from СH₂-groups,

rocking); 672 (sh), 659 ν_as(C–S–C); 622 ν_s(C–S–C).

The preparation of (acetylacetonate-κ²O,O⁰)(7-oxa-

4,10-dithiatridecane-κ²S,S⁰)palladium

(II) tetrafluoroborate (3b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(133 mg, 0.356 mmol) was dissolved in

16.5 ml of CH₂Cl₂, and 7-oxa-4,10-dithiatridecane (0.8 ml

of solution (0.446 M), 0.356 mmol) was added, forming a

yellow solution. The reaction mixture was stirred for

3.0 h at room temperature. The resulting yellow solution

was concentrated to approximately 4 ml under vacuum.

The addition of diethyl ether (25 ml) resulted in a yellow

precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to pro-

duce complex 3b as a yellow powder (121 mg, 66%). Anal.

Calcd for C₁₅H₂₉BF₄O₃PdS₂: C, 35.00; H, 5.68; S, 12.46.

Found: C, 34.61; H, 5.67; S, 11.87. ESI-MS (positive ion

mode, MeCN): m/z 427.06 [M⁺]. ¹H NMR (400 MHz,

CDCl₃, 25^ꢂC): δ 5.57 (s, 0.4H, CH_acac), 5.54 (s, 0.6H,

CH_acac), 4.5–3.5 (m, 4H, CH₂O), 3.4–2.9 (m, 4H, CH₂S),

2.9–2.4 (m, 4H, CH₂S), 2.13 (s, 2.4H, CH_3,acac), 2.09 (s,

3.6H, CH_3,acac), 1.09 (dt, J = 7.3 Hz, 6H, CH₃). ¹³C{¹H}

NMR (101 MHz, CDCl₃, 25^ꢂC): δ 187.05 (s, minor, C_CO-

_acac), 186.68 (s, C_CO-acac), 101.39 (s, minor, C_CH-acac),

101.28 (s, C_CH-acac), 67.46 (s, br, CH₂O), 66.60 (s, minor,

CH₂O), 37.08 (s, br, CH₂S), 36.85 (s, br, CH₂S), 36.20

(s, br, CH₂S), 33.98 (s, br, CH₂S), 26.71 (s, minor, C_Me-

_acac), 26.61 (s, C_Me-acac), 21.71 (br, CH₂), 21.20 (s, br,

CH₂), 13.52 (s, minor, CH₃), 13.38 (s, CH₃). IR (film, KBr

plate, cm^ꢀ1): 3106 ν(C–H from CH in acac); 2965 ν_as(C–H

from CH₃); 2934 ν_as(C–H from СH₂-groups) and ν_as(C–H

from CH₃in acac); 2870 ν_s(C–H from CH₃) and ν_s(C–H

from СH₂-groups); 1561 ν(C=O and C=C in acac); 1521

ν(C=C and C=O in acac); 1478 (sh), 1461 δ_as(C–H from

C-CH₃) and δ (HCH from CH₂-CH₃, scissoring); 1426 δ

(HCH from O-CH₂and S-CH₂, scissoring) and δ(C–H

from CH in acac, plane); 1368 δ_s(C–H from C-CH₃) and δ

(CCH from O-CH₂-CH₂, wagging) with δ (HCH from S-

CH₂, scissoring); 1294 (sh), 1276 δ (CCH from S-CH₂-

CH₂, wagging) with δ (CCH from O-CH₂-CH₂, twisting)

and

δ (CCH from CH₂-CH₂-CH₃, wagging); 1247

(sh) acac-chelate deformations and δ (CCH from O-CH₂-

CH₂, twisting) with δ (CCH from S-CH₂-CH₂, wagging)

and δ (CCH from CH₂-CH₂-CH₃, twisting); 1200, 1186 δ

(CCH from S-CH₂-CH₂and O-CH₂-CH₂, twisting) and

8 of 27

SUSLOV ET AL.

δ (CCH from CH₂-CH₂-CH₃, twisting); 1102 ν_as(B–F) and

ν_as(C–O–C); 1054 ν_as(B–F) and ν(C–C–O); 1034 ν_as(B–F)

and ν_s(C–O–C) and δ(C–H from CH₃in acac, rocking)

and acac-chelate deformations; 963 ν(C–C–S from S-CH₂-

CH₂-CH₃) and δ(C–H from CH₃, rocking); 940 acac-

chelate deformations and ν_as(C–CH₃in acac); 904 ν(C–C

from CH₂-CH₂-CH₃); 869 (sh) ν(C–C–S from S-CH₂-CH₂-

O) and skeletal stretching vibrations; 817 δ(C–H from

CH in acac, off-plane) and δ(C–H from S-CH₂-СH₂-O,

rocking); 789 ν_s(B–F) and δ(C–H from S-CH₂-СH₂-O,

rocking); 765, 744 δ(C–H from СH₂-groups,

rocking); 693 ν_as(C–S–C); 664 acac-chelate deformations

and ν_s(C–CH₃in acac); 636 ν_s(C–S–C).

The preparation of di-μ-(2,10-dimethyl-6-oxa-

3,9-dithiaundecane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] (4a) was as follows. 2,10-Dimethyl-6-oxa-

3,9-dithiaundecane (97 mg, 0.436 mmol) was dissolved

in 10 ml of CH₂Cl₂, and PdCl₂(cod) (124 mg,

0.434 mmol) was added, forming an orange solution.

The reaction mixture was stirred for 2 h at room tem-

perature. The resulting yellow solution was concen-

trated to approximately 3 ml under vacuum. The

addition of diethyl ether (16 ml) resulted in a yellow

precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to

produce complex 4a as a yellow powder (154 mg,

89%). Anal. Calcd for C₁₀H₂₂Cl₂OPdS₂: C, 30.05; H,

5.55; S, 16.04. Found: C, 30.88; 5.58, S, 15.79.

976, 971 ν(C–C–S from S-CH-(CH₃)₂); 953 δ(C–H from

CH₃, rocking), 931, 877 ν(C–C–C from CH-(CH₃)₂);

852 ν(C–C–S from S-CH₂-CH₂-O) and skeletal

stretching vibrations; 803, 776 δ(C–H from СH₂-

groups, rocking); 686 and 665 ν_as(C–S–C); 632 and

619 ν_s(C–S–C).

The

preparation

of

(acetylacetonate-κ²O,O⁰)

(2,10-dimethyl-6-oxa-3,9-dithiaundecane-κ²S,S⁰)palla-

dium (II) tetrafluoroborate (4b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(136 mg, 0.363 mmol) was dissolved

in 16 ml of CH₂Cl₂, and 2,10-dimethyl-6-oxa-

3,9-dithiaundecane (0.8 ml of solution [0.453 M],

0.363 mmol) was added, forming a yellow solution. The

reaction mixture was stirred for 3 h at room temperature.

The resulting yellow solution was concentrated to

approximately 3 ml under vacuum. The addition of

diethyl ether (25 ml) resulted in a yellow precipitate,

which was collected, washed with diethyl ether

(2 ꢁ 10 ml), and dried (8 h) under vacuum to produce

complex 4b as a yellow powder (147 mg, 77%). Anal.

Calcd for C₁₅H₂₉BF₄O₃PdS₂: C, 35.00; H, 5.68; S, 12.46.

Found: C, 35.45; H, 5.75; S, 12.14. T_m= 118^ꢂC (with

decomposition). ESI-MS (positive ion mode, MeCN): m/z

427.06 [M⁺]. ¹H NMR (400 MHz, CDCl₃, 25^ꢂC): δ 5.52 (s,

1H, CH_acac), 4.65–3.55 (m, br, 4H, CH₂O), 3.55–3.30

(m, 2H, CHS), 3.30–2.65 (m, 4H, CH₂S), 2.08 (s, 6H,

CH_3,acac), 1.60–1.40 (m, 12H, CH₃). ¹³C{¹H} NMR

(101 MHz, CDCl₃, 25^ꢂC): δ 186.64 (s, C_CO-acac), 101.63 (s,

C_CH-acac), 67.08 (s, br, CH₂O), 39.29 (s, br, CH₂S), 35.90

(s, br, CHS), 26.63 (s, C_Me-acac), 23.22 (s, CH₃), 20.48 (s,

CH₃). IR (film, KBr plate, cm^ꢀ1): 3114, 3066 ν(C–H from

CH in acac); 2969 ν_as(C–H from CH₃); 2929 ν_as(C–H from

S-CH₂-СH₂-O) and ν_as(C–H from CH₃in acac); 2871 ν(C–

H from CH) and ν_s(C–H from CH₃) and ν_s(C–H from S-

CH₂and O-CH₂); 1560 ν(C=O and C=C in acac); 1521

ν(C=C and C=O in acac); 1460 δ_as(C–H from C-CH₃);

1429 δ (HCH from O-CH₂, scissoring) with δ (HCH from

S-CH₂, scissoring) and δ(C–H from CH in acac, plane);

1411 δ (HCH from S-CH₂, scissoring) and δ (HCH

from O-CH₂, scissoring); 1387 (sh) and 1369 δ_s(C–H from

C-CH₃in i-Pr, doublet); 1367 additional δ_s(C–H from

C-CH₃in acac) and δ (CCH from O-CH₂-CH₂, wagging)

with δ (HCH from S-CH₂, scissoring); 1293(sh) δ (CCH

from S-CH₂-CH₂, wagging) with δ (CCH from O-CH₂-

CH₂, twisting); 1276 δ (CCH from O-CH₂-CH₂, twisting)

T

_m= 164^ꢂC. ESI-MS (positive ion mode, MeCN): m/z

364.98 [M⁺ꢀ Cl]. H NMR (400 MHz, CDCl₃, 25^ꢂC): δ

4.24 (t, J = 6.4 Hz, 3.2H, CH₂O), 4.11 (t, J = 6.1 Hz,

0.7H, CH₂O), 4.05 (br, 0.1H CH₂O), 3.56 (hept,

J = 6.4 Hz, 2H, CHS), 2.99 (br, 4H, CH₂S), 1.50 (m,

1

12H, CH₃). C{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ

13

69.67 (s, CH₂O), 68.96 (s, minor, CH₂O), 41.43

(s, minor, CH₂S), 40.94 (s, CH₂S), 34.34 (s, CHS), 34.03

(s, minor, CHS), 20.04 (br, CH₃). IR (KBr disk, cm^ꢀ1):

2975(sh), 2970 ν_as(C–H from CH₃); 2926 ν_as(C–H from

S-CH₂and O-CH₂); 2877 (sh) ν(C–H from CH); 2866

ν_s(C–H from CH₃) and ν_s(C–H from S-CH₂and

O-CH₂); 1465, 1447 δ_as(C–H from C-CH₃); 1402 δ

(HCH from S-CH₂, scissoring) and δ (HCH from

O-CH₂, scissoring); 1385 and 1368 δ_s(C–H from C-CH₃,

doublet); 1368 additional δ (HCH from S-CH₂, scissor-

ing) with δ (CCH from O-CH₂-C, wagging) and δ(C–H

from CH); 1296 δ (CCH from S-CH₂-CH₂, wagging)

with δ (CCH from O-CH₂-CH₂, twisting); 1252 δ (CCH

from O-CH₂-CH₂, twisting) with δ (CCH from S-CH₂-

CH₂, wagging); 1236 δ(C–H from CH₃, rocking); 1203,

with

δ

(CCH from S-CH₂-CH₂, wagging); 1257

(sh) acac-chelate deformations and δ(C–H from CH₃,

rocking); 1199, 1182 δ (CCH from S-CH₂-CH₂and

O-CH₂-CH₂, twisting); 1157 δ(C–H from CH₃,

rocking); 1096 ν_as(B–F) and ν_as(C–O–C); 1055 ν_as(B–F)

and ν(C–C–O); 1036 ν_as(B–F) and ν_s(C–O–C) and δ(C–H

from CH₃in acac, rocking) and acac-chelate deforma-

tions;962 δ(C–H from CH₃, rocking); 940 acac-chelate

1184

δ

(CCH from S-CH₂-CH₂and O-CH₂-CH₂,

twisting);

1154 δ(C–H from CH₃, rocking);

1121, 1104 ν_as(C–O–C); 1059 ν(C–C–O); 1034, 1020

(sh) ν_s(C–O–C); 980 δ(C–H from CH₃, rocking);

SUSLOV ET AL.

9 of 27

deformations and ν_as(C–CH₃in acac); 876, 866 ν(C–C–C

from CH-(CH₃)₂); 855 ν(C–C–S from S-CH₂-CH₂-O) and

skeletal stretching vibrations; 819 δ(C–H from CH in

acac, off-plane) and δ(C–H from S-CH₂-СH₂-O, rocking);

789 ν_s(B–F) and δ(C–H from S-CH₂-СH₂-O, rocking);

765 (sh), 732 δ(C–H from СH₂-groups, rocking);

695 ν_as(C–S–C); 666 acac-chelate deformations and ν_s(C–

CH₃in acac); 636 ν_s(C–S–C).

CH₃); 849 ν(C–C–S from S-CH₂-CH₂-O) and skeletal

stretching vibrations, 802, 780, 747, 729 δ(C–H from

СH₂-groups, rocking); 667 ν_as(C–S–C); 638, 614 (very

weak) ν_s(C–S–C).

The preparation of (acetylacetonate-κ²O,O⁰)(8-oxa-

5,11-dithiapentadecane-κ²S,S⁰)palladium

(II) tetrafluoroborate (5b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(117 mg, 0.314 mmol) was dissolved in

16 ml of CH₂Cl₂, and 8-oxa-5,11-dithiapentadecane

(0.8 ml of solution (0.492 M), 0.314 mmol) was added,

forming a yellow solution. The reaction mixture was

stirred for 3.0 h at room temperature. The resulting yel-

low solution was concentrated to approximately 3 ml

under vacuum. The addition of diethyl ether (25 ml)

resulted in a yellow precipitate, which was collected,

washed with diethyl ether (2 ꢁ 10 ml), and dried (8 h)

under vacuum to produce complex 5b as a yellow powder

(115 mg, 68%). Anal. Calcd for C₁₇H₃₃BF₄O₃PdS₂: C,

37.62; H, 6.13; S, 11.81. Found: C, 37.26; H, 6.10; S, 11.35.

ESI-MS (positive ion mode, MeCN): m/z 455.09 [M⁺]. ¹H

NMR (400 MHz, CDCl₃, 25^ꢂC): δ 5.59 (s, 0.2H, CH_acac),

5.57 (s, 0.4H, CH_acac), 5.54 (s, 0.4H, CH_acac), 4.5–3.6 (m,

4H, CH₂O), 3.4–3.0 (m, 4H, CH₂S), 3.0–2.4 (m, 4H,

CH₂S), 2.13 (s, 3.6H, CH_3,acac), 2.09 (s, 2.4H, CH_3,acac),

1.9–1.6 (m, 4H, CH₂), 1.6–1.4 (m, 4H, CH₂), 0.95

(t, J = 7.4 Hz, 6H, CH₃). ¹³C{¹H} NMR (101 MHz, CDCl₃,

25^ꢂC): δ 187.07 (s, minor, C_CO-acac), 186.68 (s, C_CO-acac),

101.42 (s, minor, C_CH-acac), 101.31 (s, C_CH-acac), 67.57

(s, br, CH₂O), 66.62 (s, minor, CH₂O), 39.11 (s, br, CH₂S),

37.04 (s, minor, CH₂S), 34.96 (s, CH₂S), 30.25 (s, minor,

CH₂), 29.73 (s, br, CH₂), 26.74 (s, minor, C_Me-acac), 26.63

(s, C_Me-acac), 22.19 (s, minor, CH₂), 22.02 (s, CH₂), 13.62

(s, minor, CH₃), 13.58 (s, CH₃). IR (film, KBr plate,

cm^ꢀ1): 3107 ν(C–H from CH in acac); 2958 ν_as(C–H from

CH₃); 2932 ν_as(C–H from S-CH₂-СH₂-O) and ν_as(C–H

from CH₃in acac); 2873 ν_s(C–H from CH₃) and ν_s(C–H

from СH₂-groups); 1560 ν(C=O and C=C in acac); 1521

ν(C=C and C=O in acac); 1465 δ_as(C–H from C-CH₃)

and δ (HCH from CH₂-CH₂-CH₃, scissoring); 1425 δ

(HCH from S-CH₂-СH₂-O, scissoring) and δ(C–H from

CH in acac, plane); 1369 δ_s(C–H from C-CH₃) and δ

(CCH from O-CH₂-CH₂, wagging) with δ (HCH from S-

CH₂, scissoring); 1294 (sh), 1277 δ (CCH from S-CH₂-

CH₂, wagging) with δ (CCH from O-CH₂-CH₂, twisting)

and δ (CCH from CH₂-CH₂-CH₂-CH₃, wagging); 1257

(sh) acac-chelate deformations; 1232 δ (CCH from CH₂-

CH₂-CH₂-CH₃, twisting) and δ (CCH from O-CH₂-CH₂,

twisting) with δ (CCH from S-CH₂-CH₂, wagging); 1198,

1186 (sh) δ (CCH from S-CH₂-CH₂and O-CH₂-CH₂,

twisting) and δ (CCH from CH₂-CH₂-CH₂-CH₃, twist-

ing); 1099 ν_as(B–F) and ν_as(C–O–C); 1056 ν_as(B–F) and

ν(C–C–O); 1036 ν_as(B–F) and ν_s(C–O–C) and δ(C–H from

CH₃in acac, rocking) and acac-chelate deformations;

The

preparation

of

di-μ-(8-oxa-5,-

11-dithiapentadecane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] (5a) was as follows. 8-Oxa-5,11-dithiapentadecane

(94 mg, 0.373 mmol) was dissolved in 10 ml of CH₂Cl₂,

and PdCl₂(cod) (106 mg, 0.372 mmol) was added, for-

ming a yellow solution. The reaction mixture was stirred

for 6 h at room temperature. The resulting yellow solu-

tion was concentrated to approximately 4 ml under vac-

uum. The addition of diethyl ether (20 ml) resulted in a

yellow precipitate, which was collected, washed with

diethyl ether (2 ꢁ 10 ml), and dried (8 h) under vacuum

to produce complex 5a as a yellow powder (121 mg, 76%).

Anal. Calcd for C₁₂H₂₆Cl₂OPdS₂: C, 33.69; H, 6.13; S,

14.99. Found: C, 33.61; H, 6.11; S, 14.55. ESI-MS (positive

ion mode, MeCN): m/z 393.01 [M⁺ꢀ Cl]. ¹H NMR

(400 MHz, CDCl₃, 25^ꢂC): δ 4.19 (t, J = 6.6 Hz, 2.5H,

CH₂O), 4.06 (m (t, overlapping, J = 6.6 Hz), 1.5H,

CH₂O), 3.30–3.00 (m, br, overlapping, 1.5H, CH₂S), 2.99

(t, br, overlapping, J = 6.4 Hz, 2.5H, CH₂S), 1.80–1.69

(m (p, overlapping, J = 7.4 Hz), 4H, CH₂), 1.46

(m (h, overlapping, J = 7.3 Hz), 4H, CH₂), 0.92

(m (t, overlapping, J = 7.3 Hz, 6H, CH₃). ¹³C{¹H} NMR

(101 MHz, CDCl₃, 25^ꢂC): δ 69.79 (s, CH₂O), 69.21

(s, minor, CH₂O), 36.69 (s, minor, CH₂S), 36.06 (s, CH₂S),

36.01 (sh, minor, CH₂S), 35.68 (s, CH₂S), 30.35 (s, minor,

CH₂), 30.01 (s, CH₂), 22.09 (s, minor, CH₂), 22.02

(s, CH₂), 13.73 (s, minor, CH₃), 13.68 (s, CH₃). IR (KBr

disk, cm^ꢀ1): 2958 ν_as(C–H from CH₃); 2929 ν_as(C–H from

СH₂-groups); 2870 ν_s(C–H from CH₃) and ν_s(C–H from

СH₂-groups); 1462 δ_as(C–H from C-CH₃) and δ (HCH

from CH₂-CH₂-CH₃, scissoring); 1416 δ (HCH from

O-CH₂, scissoring); 1402 δ (HCH from S-CH₂, scissoring);

1380 δ_s(C–H from C-CH₃); 1360 δ (HCH from S-CH₂,

scissoring) with δ (CCH from O-CH₂-C, wagging); 1314

(sh), 1290, 1275, 1242 (sh) δ (CCH from S-CH₂-CH₂, wag-

ging) with δ (CCH from O-CH₂-CH₂, twisting) and δ

(CCH from CH₂-CH₂-CH₂-CH₃, wagging); 1226 δ (CCH

from CH₂-CH₂-CH₂-CH₃, twisting) and δ (CCH from

O-CH₂-CH₂, twisting) with δ (CCH from S-CH₂-CH₂,

wagging); 1203, 1192 (sh) δ (CCH from S-CH₂-CH₂

and O-CH₂-CH₂, twisting) and δ (CCH from CH₂-CH₂-

CH₂-CH₃, twisting); 1111 (sh), 1100 ν_as(C–O–C); 1077,

1057 ν(C–C–O); 1042, 1023 ν_s(C–O–C); 986, 968 ν(C–C–S

from S-CH₂-CH₂-CH₂-CH₃); 953 δ(C–H from CH₃,

rocking); 942, 915, 877 ν(C–C–C from CH₂-CH₂-CH₂-

10 of 27

SUSLOV ET AL.

992 (sh) ν(C–C–S from S-CH₂-CH₂-CH₂-CH₃); 940 acac-

chelate deformations and ν_as(C–CH₃in acac); 923, 872

ν(C–C–C from CH₂-CH₂-CH₂-CH₃); 858 (sh) ν(C–C–S

from S-CH₂-CH₂-O) and skeletal stretching vibrations;

823 δ(C–H from CH in acac, off-plane) and δ(C–H from

S-CH₂-СH₂-O, rocking); 787 ν_s(B–F) and δ(C–H from S-

CH₂-СH₂-O, rocking); 763, 744, 739 (sh) δ(C–H from

СH₂-groups, rocking); 693 ν_as(C–S–C); 665 acac-chelate

deformations and ν_s(C–CH₃in acac), 636 ν_s(C–S–C).

729 δ(C–H from СH₂-groups, rocking); 664 ν_as(C–S–C);

638 (sh), 619 ν_s(C–S–C).

The

preparation

of

(acetylacetonate-κ²O,O⁰)

(2,12-dimethyl-7-oxa-4,10-dithiatridecane-κ²S,S⁰)palla-

dium (II) tetrafluoroborate (6b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(118 mg, 0.316 mmol) was dissolved

in 15 ml of CH₂Cl₂, and 2,12-dimethyl-7-oxa-

4,10-dithiatridecane (0.8 ml of solution [0.395 M],

0.316 mmol) was added, forming a yellow solution. The

reaction mixture was stirred for 3 h at room temperature.

The resulting yellow solution was concentrated to

approximately 3 ml under vacuum. The addition of

diethyl ether (25 ml) resulted in a yellow precipitate,

which was collected, washed with diethyl ether

(2 ꢁ 10 ml), and dried (8 h) under vacuum to produce

complex 6b as a yellow powder (107 mg, 62%). Anal.

Calcd for C₁₇H₃₃BF₄O₃PdS₂: C, 37.62; H, 6.13; S, 11.81.

Found: C, 37.31; H, 6.13; S, 11.63. ESI-MS (positive ion

mode, MeCN): m/z 455.09 [M⁺]. ¹H NMR (400 MHz,

CDCl₃, 25^ꢂC): δ 5.57 (s, 0.6H, CH_acac), 5.54 (s, 0.4H,

CH_acac), 4.6–3.6 (m, br, 4H, CH₂O), 3.50–3.05 (m, 4H,

CH₂S), 3.05–2.50 (m, 4H, CH₂S), 2.20–2.00 (m, 8H,

CH_3,acac+CH), 1.09 (d, J = 7.2 Hz, 12H, CH₃). ¹³C{¹H}

NMR (101 MHz, CDCl₃, 25^ꢂC): δ 187.10 (s, C_CO-acac),

186.67 (s, minor, C_CO-acac), 101.44 (s, C_CH-acac), 101.29 (s,

minor, C_CH-acac), 66.59 (s, br, CH₂O), 43.58 (s, CH₂S),

37.64 (s, CH₂S), 28.16 (s, CH), 26.75 (s, minor, C_Me-acac),

26.60 (s, C_Me-acac), 23.00–21.00 (m, br, CH₃). IR (film, KBr

plate, cm^ꢀ1): 3115 ν(C–H from CH in acac); 2960 ν_as(C–H

from CH₃); 2933 ν_as(C–H from S-CH₂-СH₂-O) and ν_as(C–

H from CH₃in acac); 2874 ν(C–H from CH) and ν_s(C–H

from CH₃) and ν_s(C–H from S-CH₂and O-CH₂); 1560

ν(C=O and C=C in acac); 1521 ν(C=C and C=O in acac);

1466 δ_as(C–H from C-CH₃); 1422 δ (HCH from S-CH₂-

СH₂-O, scissoring) and δ(C–H from CH in acac, plane);

1385 (sh) and 1368 δ_s(C–H from C-CH₃, doublet); 1368

additional δ_s(C–H from C-CH₃) and δ (CCH from O-CH₂-

CH₂, wagging) with δ (HCH from S-CH₂, scissoring);

1324 δ (CCH from S-CH₂-CH₂in iBu, wagging); 1293

(sh) δ (CCH from S-CH₂-CH₂, wagging) with δ (CCH

from O-CH₂-CH₂, twisting); 1277 δ (CCH from O-CH₂-

CH₂, twisting) with δ (CCH from S-CH₂-CH₂, wagging)

and δ (CCH from S-CH₂-CH (CH₃)₂, twisting); 1262

(sh) acac-chelate deformations δ (CCH from S-CH₂-CH₂

and O-CH₂-CH₂, twisting); 1200, 1181 δ (CCH from S-

CH₂-CH₂and O-CH₂-CH₂, twisting); 1170 δ(C–H

from CH₃, rocking); 1103 ν_as(B–F) and ν_as(C–O–C); 1057

ν_as(B–F) and ν(C–C–O); 1036 ν_as(B–F) and ν_s(C–O–C) and

δ(C–H from CH₃in acac, rocking) and acac-chelate defor-

mations; 991(sh) δ(C–H from CH₃, rocking);

The preparation of di-μ-(2,12-dimethyl-7-oxa-

4,10-dithiatridecane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] (6a) was as follows. 2,12-Dimethyl-7-oxa-

4,10-dithiatridecane (100 mg, 0.398 mmol) was dissolved

in 5 ml of CH₂Cl₂, and PdCl₂(cod) (113 mg, 0.397 mmol)

was added, forming a yellow solution. The reaction

mixture was stirred for 3 h at room temperature. The

resulting yellow solution was concentrated to approxi-

mately 2 ml under vacuum. The addition of diethyl ether

(20 ml) resulted in a yellow precipitate, which was

collected, washed with diethyl ether (2 ꢁ 10 ml), and

dried (8 h) under vacuum to produce complex 6a as a

yellow powder (134 mg, 79%). Anal. Calcd for

C₁₂H₂₆Cl₂OPdS₂: C, 33.69; H, 6.13; S, 14.99. Found: C,

33.63; H, 6.11; S, 14.70 ESI-MS (positive ion mode,

MeCN): m/z 393.01 [M⁺ꢀ Cl]. ¹H NMR (400 MHz,

CDCl₃, 25^ꢂC): δ 4.22 (t, J = 6.7 Hz, 3.2H, CH₂O), 4.09

(t, J = 6.7 Hz), 0.8H, CH₂O), 3.03 (s, br, 0.8H, CH₂S), 2.97

(t, J = 6.7 Hz, 3.2H, CH₂S), 2.74 (s, br, 4H, CH₂S), 2.08

(hept, J = 6.8 Hz, 1.6H, CH), 1.93 (s, br, 0.4H, CH), 1.06

(two overlapping doublets, J = 6.7 Hz), 12H, CH₃). ¹³C

{¹H} NMR (101 MHz, CDCl₃, 25^ꢂC): δ 69.99 (s, CH₂O),

69.35 (s, minor, CH₂O), 45.45 (s, minor, CH₂S), 44.91

(s, CH₂S), 36.99 (s, minor, CH₂S), 36.93 (s, CH₂S), 27.57

(s, CH), 22.18 (s, minor, CH₃), 22.12 (s, CH₃). IR (KBr

disk, cm^ꢀ1): 2958 ν_as(C–H from CH₃); 2929 ν_as(C–H from

S-CH₂and O-CH₂); 2897 ν(C–H from CH); 2870 ν_s(C–H

from CH₃) and ν_s(C–H from S-CH₂and O-CH₂); 1464

δ_as(C–H from C-CH₃); 1412 δ (HCH from S-CH₂in iBu,

scissoring) and δ (HCH from O-CH₂, scissoring); 1403 δ

(HCH from S-CH₂, scissoring); 1386 and 1366 δ_s(C–H

from C-CH₃, doublet); 1366 additional δ (HCH from

S-CH₂, scissoring) with δ (CCH from O-CH₂-C, wagging);

1338 δ(C–H from CH in iBu); 1323 δ (CCH from S-CH₂-

CH₂in iBu, wagging); 1291 δ (CCH from S-CH₂-CH₂,

wagging) with δ (CCH from O-CH₂-CH₂, twisting); 1261

δ (CCH from O-CH₂-CH₂, twisting) with δ (CCH from

S-CH₂-CH₂, wagging) and δ (CCH from S-CH₂-CH

(CH₃)₂, twisting); 1222, 1202 δ (CCH from S-CH₂-CH₂

and O-CH₂-CH₂, twisting); 1172 δ(C–H from CH₃,

rocking); 1114 (sh), 1101 ν_as(C–O–C); 1082, 1058 ν(C–C–

O); 1042, 1021 ν_s(C–O–C); 984 δ(C–H from CH₃,

rocking); 968 ν(C–C–S from S-CH₂-CH-(CH₃)₂); 954, 928,

863 ν(C–C–C from CH₂-CH-(CH₃)₂); 815, 783, 736 (sh),

965

(sh)

ν(C–C–S

from

S-CH₂-CH-(CH₃)₂);

940 acac-chelate deformations and ν_as(C–CH₃in acac);

895 ν(C–C–C from CH₂-CH-(CH₃)₂); 814 δ(C–H from CH

SUSLOV ET AL.

11 of 27

in acac, off-plane) and δ(C–H from СH₂-groups, rocking);

S-CH₂-CH₂-O) and skeletal stretching vibrations;

813, 789, 760, 725 δ(C–H from СH₂-groups,

rocking); 674 (sh), 666 ν_as(C–S–C); 644 (sh), 624 (very

weak) ν_s(C–S–C).

788

ν_s(B–F)

and

δ(C–H

from

СH₂-groups,

rocking); 764, 729 δ(C–H from СH₂-groups,

rocking); 693 ν_as(C–S–C); 665 acac-chelate deformations

and ν_s(C–CH₃in acac); 636 ν_s(C–S–C).

The preparation of (acetylacetonate-κ²O,O⁰)(10-oxa-

7,13-dithianonadecane-κ²S,S⁰)palladium

The

preparation

of

di-μ-(10-oxa-7,-

13-dithianonadecane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] (7a) was as follows. 10-oxa-7,13-dithianonadecane

(94 mg, 0.307 mmol) was dissolved in 10 ml of CH₂Cl₂,

and PdCl₂(cod) (87 mg, 0.305 mmol) was added, forming

a yellow solution. The reaction mixture was stirred for

3 h at room temperature. The resulting yellow solution

was concentrated to approximately 2 ml under vacuum.

The addition of diethyl ether (20 ml) resulted in a yellow

precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to pro-

duce red brick powder. The residue was recrystallized

from CH₂Cl₂-diethyl ether mixture to give 7a (73 mg,

50%). Anal. Calcd for C₁₆H₃₄Cl₂OPdS₂: C, 39.71; H,

7.08; S, 13.25. Found: C, 39.65; H, 7.12; S, 12.94. ESI-MS

(II) tetrafluoroborate (7b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(83 mg, 0.222 mmol) was dissolved in

16 ml of CH₂Cl₂, and 10-oxa-7,13-dithianonadecane

(0.8 ml of solution (0.279 M) in CH₂Cl₂, 0.223 mmol)

was added, forming a yellow solution. The reaction

mixture was stirred for 3.0 h at room temperature. The

resulting yellow solution was concentrated to approxi-

mately 2 ml under vacuum. The addition of n-pentane

(12 ml) resulted in a yellow precipitate, which was

collected, washed with n-pentane (2 ꢁ 10 ml), and dried

(8 h) under vacuum to produce complex 7b as a

yellow oily powder (81 mg, 60%). Anal. Calcd for

C₂₁H₄₁BF₄O₃PdS₂: C, 42.11; H, 6.90; S, 10.71. Found: C,

42.17; H, 6.88; S, 10.15. ESI-MS (positive ion mode,

1

(positive ion mode, MeCN): m/z 449.08 [M⁺ꢀ Cl]. H

MeCN): m/z 511.15 [M⁺]. H NMR (400 MHz, CDCl₃,

NMR (400 MHz, CDCl₃, 25^ꢂC): δ 4.18 (t, J = 6.6 Hz,

2.5H, CH₂O), 4.10–3.70 (m (t, overlapping, J = 6.1 Hz),

1.5H, CH₂O), 3.25–3.00 (m, br, overlapping, 1.5H, CH₂S),

2.98 (t, br, overlapping, J = 6.6 Hz, 2.5H, CH₂S), 2.90–

2.65 (m, br, 4H, CH₂S), 1.97–1.68 (m (p, overlapping,

J = 7.8 Hz), 4H, CH₂), 1.50–1.36 (m, br, 4H, CH₂), 1.34–

1.19 (m, br, 8H, CH₂), 0.92 (m, br, 6H, CH₃). ¹³C{¹H}

NMR (101 MHz, CDCl₃, 25^ꢂC): δ 69.79 (s, CH₂O), 69.72

(s, minor, CH₂O), 36.97 (s, minor, CH₂S), 36.35 (s, CH₂S),

36.02 (minor, CH₂S), 35.66 (s, CH₂S), 31.38 (s, minor,

CH₂), 31.33 (s, CH₂), 28.58 (s, minor, CH₂), 28.44 (s,

CH₂), 28.31 (s, minor, CH₂), 27.96 (s, CH₂), 22.53

(s, minor, CH₂), 22.50 (s, CH₂), 14.04 (m, br, CH₃). IR

(KBr disk, cm^ꢀ1): 2957 ν_as(C–H from CH₃); 2926 ν_as(C–H

from СH₂-groups); 2870 (sh), 2858 ν_s(C–H from CH₃) and

ν_s(C–H from СH₂-groups); 1461 (sh), 1456 (sh) δ_as(C–H

from C-CH₃) and δ (HCH from SCH₂-(CH₂)₄-CH₃, scis-

soring); 1416 δ (HCH from O-CH₂, scissoring); 1403 δ

(HCH from S-CH₂, scissoring); 1377 δ_s(C–H from

C-CH₃); 1371 δ (HCH from S-CH₂, scissoring) with δ

(CCH from O-CH₂-C, wagging); 1362 δ (CCH from

25^ꢂC): δ 5.60 (s, 0.8H, CH_acac), 5.56 (s, 0.2H, CH_acac), 4.5–

3.5 (m, 4H, CH₂O), 3.4–3.1 (m, 4H, CH₂S), 3.1–2.4 (m,

4H, CH₂S), 2.15 (s, 4.9H, CH_3,acac), 2.11 (s, 1.1H,

CH_3,acac), 1.81 (s, br, 4H, CH₂), 1.48 (s, br, 4H, CH₂), 1.32

(s, br, 8H, CH₂), 0.90 (s, br, 6H, CH₃). ¹³C{¹H} NMR

(101 MHz, CDCl₃, 25^ꢂC): δ 187.07 (s, minor, C_CO-acac),

186.68 (s, C_CO-acac), 101.32 (s, C_CH-acac), 100.51 (s, minor,

C_CH-acac), 67.58 (s, br, CH₂O), 67.13 (s, br, minor, CH₂O),

39.17 (s, br, CH₂S), 38.10 (s, br, minor, CH₂S), 35.22

(s, br, minor, CH₂S), 34.42 (s, br, CH₂S), 32.17 (s, br,

CH₂), 31.24 (s, br, minor, CH₂), 28.48 (s, br, CH₂), 28.35–

27.25 (m, br, CH₂), 26.73 (s, minor, C_Me-acac), 26.63

(s, C_Me-acac), 22.44 (s, br, CH₂), 13.98 (s, br, CH₃). IR (film,

KBr plate, cm^ꢀ1): 3113 ν(C–H from CH in acac); 2955

ν_as(C–H from CH₃); 2929 ν_as(C–H from СH₂-groups) and

ν_as(C–H from CH₃in acac); 2869, 2859 ν_s(C–H from CH₃)

and ν_s(C–H from СH₂-groups); 1560 ν(C=O and C=C in

acac); 1521 ν(C=C and C=O in acac); 1465, 1459

(sh) δ_as(C–H from C-CH₃) and δ (HCH from SCH₂-

(CH₂)₄-CH₃, scissoring); 1425 δ (HCH from S-CH₂-

СH₂-O, scissoring); 1401 δ(C–H from CH in acac, plane);

1369 δ_s(C–H from C-CH₃) and δ (CCH from O-CH₂-CH₂,

wagging) with δ (HCH from S-CH₂, scissoring); 1294

(sh), 1279 δ (CCH from S-CH₂-CH₂, wagging) with δ

(CCH from O-CH₂-CH₂, twisting) and δ (CCH from

SCH₂-(CH₂)₄-CH₃, twisting); 1245 (sh) acac-chelate defor-

mations; 1201, 1186 δ (CCH, twisting, from O-CH₂-CH₂,

SCH₂-(CH₂)₄-CH₃and S-CH₂-CH₂, respectively); 1098

ν_as(B–F) and ν_as(C–O–C); 1057 ν_as(B–F) and ν(C–C–O);

1036 ν_as(B–F) and ν_s(C–O–C) and δ(C–H from CH₃in

SCH₂-(CH₂)₄-CH₃, wagging); 1344

δ

(CCH from

O-CH₂-C, wagging) with δ (HCH from S-CH₂, scissoring);

1292, 1263 δ (CCH from S-CH₂-CH₂, wagging) with δ

(CCH from O-CH₂-CH₂, twisting) and δ (CCH from

SCH₂-(CH₂)₄-CH₃, twisting); 1215, 1205, 1174 δ (CCH,

twisting, from O-CH₂-CH₂, SCH₂-(CH₂)₄-CH₃and S-CH₂-

CH₂, respectively); 1122 (sh), 1103 ν_as(C–O–C); 1077,

1052 (sh) ν(C–C–O); 1045, 1034, 1018 ν_s(C–O–C);

984, 967 (sh) ν(C–C–S from S-CH₂-CH₂-(CH₂)₃-CH₃);

952 δ(C–H from CH₃, rocking); 917, 888 (sh), 874 (sh),

ν(C–C–C from CH₂-(CH₂)₄-CH₃); 863 ν(C–C–S from

acac,

rocking)

and

acac-chelate

deformations;

984 (sh) ν(C–C–S from S-CH₂-CH₂-(CH₂)₃-CH₃);

12 of 27

SUSLOV ET AL.

940 acac-chelate deformations and ν_as(C–CH₃in acac);

865 ν(C–C–S from S-CH₂-CH₂-O) and skeletal stretching

vibrations; 816 δ(C–H from CH in acac, off-plane)

and δ(C–H from S-CH₂-СH₂-O, rocking); 788 ν_s(B–F)

and δ(C–H from S-CH₂-СH₂-O, rocking); 763, 728 δ(C–H

818, 804 skeletal stretching vibrations and δ(C–H from

S-CH₂-СH₂-O, rocking); 769, 698 δ (CCH from Ph, off-

plane) and δ(C–H from S-CH₂-СH₂-O, rocking);

668 (sh) ν_as(C–S–C); 642 (sh) ν_s(C–S–C); 619, 591, 564 ring

deformations (off-plane).

from

СH₂-groups,

rocking);

693

ν_as(C–S–C);

The preparation of (acetylacetonate-κ²O,O⁰)(5-oxa-

666 acac-chelate deformations and ν_s(C–CH₃in acac);

635 ν_s(C–S–C).

1,9-diphenyl-2,8-dithianonane-κ²S,S⁰)palladium

(II) tetrafluoroborate (8b) was as follows. [Pd (acac)

(MeCN)₂]BF₄(103 mg, 0.275 mmol) was dissolved in

15 ml of CH₂Cl₂, and 5-oxa-2,8-dithianonane (0.8 ml of

solution (0.345 M), 0.276 mmol) was added, forming a

yellow solution. The reaction mixture was stirred for

1.0 h at room temperature. The resulting orange solution

was concentrated to approximately 3 ml under vacuum.

The addition of diethyl ether (25 ml) resulted in a yellow

precipitate, which was collected, washed with diethyl

ether (2 ꢁ 10 ml), and dried (8 h) under vacuum to pro-

duce complex 8b as a yellow powder (143 mg, 85.0%).

The

preparation

of

di-μ-(5-oxa-1,9-diphenyl-

2,8-dithianonane-κ²S,S⁰)-bis[trans-dichloropalladium

(II)] (8a) was as follows. 5-Oxa-1,9-diphenyl-

2,8-dithianonane (112 mg, 0.10 ml, 0.350 mmol) was dis-

solved in 10 ml of CH₂Cl₂, and PdCl₂(cod) (100 mg,

0.350 mmol) was added, forming an orange solution. The

reaction mixture was stirred for 7 h at room temperature.

The resulting orange solution was concentrated to

approximately 3 ml under vacuum. The addition of

diethyl ether (15 ml) resulted in an orange precipitate,

which was collected, washed with diethyl ether

(2 ꢁ 10 ml), and dried (8 h) under vacuum to produce

complex 8a as an orange powder (134 mg, 69%). Anal.

Calcd for C₁₈H₂₂Cl₂OPdS₂C, 43.60; H, 4.47; S, 12.93.

Found: 43.98; H, 4.42; S, 13.49. ESI-MS (positive ion

mode, MeCN): m/z 460.98 [M⁺ꢀ Cl]. ¹H NMR

(400 MHz, DMSO-d₆, 70^ꢂC): δ 7.60–7.20 (m, br, 10H, Ph),

3.97 (s, br, 4H, CH₂O), 3.68 (s, br, 4H, CH₂S), 2.79 (s, br,

1

The product contained races (<2%) of Et₂O by H NMR

analysis. Anal. Calcd for C₂₃H₂₉BF₄O₃PdS₂: C, 45.22; H,

4.79; S, 10.50. Found: C, 45.50; H, 4.85; S, 10.16. ESI-MS

1

(positive ion mode, MeCN): m/z 523.06 [M⁺]. H NMR

(400 MHz, CDCl₃, 25^ꢂC): δ 7.1–7.6 (m, 10H, Ph), 5.58 (s,

0.6H, CH_acac), 5.54 (s, 0.4H, CH_acac), 4.4–2.6 (m, br, 12H,

CH₂O), 2.15 (s, 3.6H, overlapping, CH_3,acac). 2.11 (s, 2.4H,

overlapping, CH_3,acac). ¹³C{¹H} NMR (101 MHz, CDCl₃,

25^ꢂC): δ 187.04 (s, C_CO-acac), 130.12 (s, Ph), 129.97(s, Ph),

129.32 (s, Ph), 129.01 (s, Ph), 128.93 (s, Ph), 101.37

(s, C_CH-acac), 68.52 (s, br, CH₂O), 26.80 (s, C_Me-acac). IR

(film, KBr plate, cm^ꢀ1): 3106 ν(C–H from CH in acac)

and ν(C–H from Ph); 3087, 3062, 3030, 3003 (sh) ν(C–H

from Ph); 2994 ν_as(C–H from S-CH₂-Ph); 2931 ν_as(C–H

from S-CH₂-СH₂-O) and ν_as(C–H from CH₃in acac); 2871

ν_s(C–H from S-CH₂-Ph)and ν_s(C–H from S-CH₂and

O-CH₂) and ν_s(C–H from CH₃in acac); 1599

(sh) ν_as(C=C from Ph); 1558 ν(C=O and C=C in acac);

1520 ν(C=C and C=O in acac); 1496 ν_as(C=C from Ph)

and δ (CCH from Ph); 1474 δ (HCH from S-CH₂-Ph, scis-

soring) and δ_as(C–H from C-CH₃); 1455 δ (CCH from Ph)

and ν_as(C=C from Ph); 1425 δ (HCH from S-CH₂-СH₂-O,

scissoring) and δ(C–H from CH in acac, plane); 1367

δ_s(C–H from C-CH₃) and δ (CCH from S-CH₂-Ph,

wagging) and δ (CCH from O-CH₂-CH₂, wagging) with δ

(HCH from S-CH₂, scissoring); 1294 (sh), 1277 δ (CCH

from S-CH₂-CH₂, wagging) with δ (CCH from O-CH₂-

CH₂, twisting) and δ (CCH from S-CH₂-Ph, twisting);

1247 (sh) acac-chelate deformations; 1199 δ (CCH

from O-CH₂-CH₂and S-CH₂-CH₂, twisting); 1184,

1159 (sh) δ (CCH from Ph, plane); 1098 ν_as(B–F) and

ν_as(C–O–C); 1056 ν_as(B–F) and ν(C–C–O); 1036 ν_as(B–F)

and ν_s(C–O–C) and δ(C–H from CH₃in acac, rocking)

and acac-chelate deformations; 1002 (sh) ν_s(C=C from

Ph); 940 acac-chelate deformations and ν_as(C–CH₃in

13

4H, CH₂S). C{¹H} NMR (101 MHz, DMSO-d₆, 70^ꢂC): δ

129.78 (s, Ph), 128.99 (s, Ph), 127.88 (s, Ph), 69.40 (s, br,

CH₂O). IR (KBr disk, cm^ꢀ1): 3105 (sh), 3085, 3061, 3029,

3002 (sh) ν(C–H from Ph); 2975 ν_as(C–H from S-CH₂-Ph);

2925 ν_as(C–H from S-CH₂and O-CH₂); 2880 ν_s(C–H from

S-CH₂-Ph); 2860 ν_s(C–H from S-CH₂and O-CH₂); 1602,

1584 ν_as(C=C from Ph); 1494 ν_as(C=C from Ph) and δ

(CCH from Ph); 1473 δ (HCH from S-CH₂-Ph, scissoring);

1454 δ (CCH from Ph) and ν_as(C=C from Ph); 1418 δ

(HCH from S-CH₂, scissoring) and δ (HCH from O-CH₂,

scissoring); 1365 δ (CCH from S-CH₂-Ph, wagging) and δ

(CCH from O-CH₂-CH₂, wagging) with δ (HCH from

S-CH₂, scissoring); 1359 δ (HCH from S-CH₂, scissoring)

with δ (CCH from O-CH₂-CH₂, wagging) and δ (CCH

from S-CH₂-Ph, wagging); 1342 (sh), 1323 (sh) δ

(CCH from Ph, plane); 1296 δ (CCH from S-CH₂-CH₂,

wagging) with δ (CCH from O-CH₂-CH₂, twisting); 1246

δ (CCH from S-CH₂-Ph, twisting) and δ (CCH from

S-CH₂-CH₂, twisting); 1202 δ (CCH from O-CH₂-CH₂and

S-CH₂-CH₂, twisting); 1185, 1155 (sh), 1143 δ (CCH from

Ph, plane); 1110 ν_as(C–O–C); 1072 ν(C–C–O) and δ (CCH

from Ph, plane); 1045 (sh), 1018 (sh) ν_s(C–O–C); 1027

ν_s(C–O–C) and

δ (CCH from Ph, plane); 1004

(sh) ν_s(C=C from Ph) with δ (CCH from Ph, plane) and

ring deformations; 958 ν (C_Ar–C–S); 917 δ (CCH from Ph,

plane); 877 ν(C–C–S from S-CH₂-CH₂-O) and skeletal

stretching vibrations; 845 δ (CCH from Ph, off-plane);

SUSLOV ET AL.

13 of 27

acac) and ν (C_Ar–C–S); 925 (sh) δ (CCH from Ph, plane);

880 ν(C–C–S from S-CH₂-CH₂-O) and skeletal stretching

vibrations; 851 δ (CCH from Ph, off-plane); 820 (sh) δ(C–H

from CH in acac, off-plane) and δ(C–H from S-CH₂-

СH₂-O, rocking); 820 (sh) skeletal stretching vibrations

and δ(C–H from S-CH₂-СH₂-O, rocking); 804 ν_s(B–F) and

δ(C–H from S-CH₂-СH₂-O, rocking); 771, 704 δ (CCH

from Ph, off-plane); 731 δ(C–H from S-CH₂-СH₂-O,

rocking); 669 (sh) ν_as(C–S–C); 663 (sh) acac-chelate defor-

mations and ν_s(C–CH₃in acac); 637 (sh) ν_s(C–S–C);

619, 568 ring deformations (off-plane).

the SHELX program.^[58]Data were corrected for absorp-

tion effects using the multiscan method (SADABS).^[59]

All nonhydrogen atoms were refined anisotropically

using SHELX.^[58]The coordinates of the hydrogen atoms

were refined using a riding model. The resulting struc-

ture was refined by the least squares method using

SHELXL. Note for Alert Level B in checkCIF/PLATON

report for 4b. The R-factor for compound 4b is high, and

this is due to the data quality, which is a consequence of

the characteristics of the crystal. There have been

repeated attempts at recrystallization, but they did not

give the best results. Due to the poor quality of the data,

geometric restraints were not investigated, and disorder

was not considered. The crystal data and experimental

details are given in Table S1 (SI). The selective bond

lengths, bond angles, and torsion angles are given in

Tables S2 and S3 (SI). Table S1 (SI) contains the CCDC

reference number of the supplementary crystallographic

data for this paper. These data can be obtained free of

charge from The Cambridge Crystallographic Data Cen-

tre (http://www.ccdc.cam.ac.uk).

Further spectroscopic details are given in Figures S6–

S40, S68–S83, and S97ꢀS106 (see SI).

2.4 | Polymerization experiments

Polymerizations were performed in a 10-ml glass reactor

equipped with a magnetic stirrer under purified argon.

The reactor was filled with norbornene as a solution in

CH₂Cl₂; the solution was kept at the desired temperature

for 15 min before the palladium complex was added.

Polymerizations were initiated by the injection of boron

or aluminum compound. After stirring, the polymers

formed were precipitated in ethanol. The precipitated

polymers were washed three times with ethanol and

dried in vacuum at 80^ꢂC for 6 h.

3 | RESULTS AND DISCUSSION

3.1 | Synthesis of oxadithioether ligands

The synthetic strategies for the oxadithioether ligands

L1–L8 are shown in Scheme 1. Two well-known methods

of synthesis were employed based on bis(2-chloroethyl)

ether, thiols, or diorganyldisulfides in the presence of

KOH or hydrazine hydrate/base.^[60–63]Methyl- and ethyl-

substituted oxadithioethers (L1, L2) were synthesized by

the reaction of potassium alkyl sulfides prepared by the

reaction of R₂S₂(R = Me, Et) and hydrazine hydrate/

KOH with chlorex (Scheme 1). The reaction of bis

(2-chloroethyl) ether with RSH/KOH produced other

oxadithioethers L3–L8. The oxadithioethers L3, L4, and

L6 are new compounds, whereas L1, L2, L5, L7, and L8

are known.^{[45,60–62,64–68]}The compounds were fully

characterized by NMR and Fourier-transform infrared

spectroscopy (FTIR). Purity of the obtained ligands was

confirmed by GC.

2.5 | Calculations

All density functional theory calculations were performed

with the ORCA program.^[46]All geometry optimizations

were run with tight convergence criteria using the BP86

functional,^[47,48]using the resolution of the identity tech-

nique.^[49]The applicability of gradient-corrected func-

tionals such as BP86 for the structural prediction of

transition metal compounds and reliable determination

of the kinetic balance are well documented.^[50–55]The

WeigendꢀAhlrichs basis sets were used.^[56,57]Triple

ξ-quality basis sets with one set of polarization functions

(def2-TZVP) were used for palladium, chlorine, and

sulfur in connection with effective core potentials for

Pd. The remaining atoms were described by slightly

smaller def2-SVP basis sets.

3.2 | Synthesis of palladium

(II) dichloride complexes

2.6 | X-ray crystallographic studies

The synthesis of complexes 1a–8a was achieved by

reacting (1,5-cyclooctadiene)palladium (II) dichloride

with one equivalent of L1–L8 in dichloromethane, which

led to the formation of trans-[PdCl₂(μ-L)]₂(1a–8a, L –

oxadithioether ligands), as depicted in Scheme 2. Two

Data were collected on a BRUKER D8 VENTURE PHO-

TON 100 CMOS diffractometer with MoK_αradiation

(λ = 0.71073 Å) using the φ and ω scans technique. The

structures were solved by direct methods using

14 of 27

SUSLOV ET AL.

SCHEME 1 Routes for oxadithioether

ligand synthesis (L1–L8). Percentages in

parentheses represent yields

SCHEME 2 Synthesis of

palladium chlorido (1a–8a) and

cationic acetylacetonato

complexes (1b–8b) with

oxadithioether ligands.

Percentages in parentheses

represent yields

sulfur atoms coordinate to palladium (II), replacing the

labile cod ligand. The new complexes were fully

characterized by NMR and FTIR spectroscopy, ESI-MS,

and elemental analysis.

appear in the 2.8–3.6 ppm range. Notably, for a solution

of 2a in dimethyl sulfoxide, raising the temperature from

25^ꢂC to 90^ꢂC causes the broad multiple -CH₂O-signals to

coalesce to a single narrower band, and peaks in the

-SCH₂CH₃and -SCH₂CH₂O- regions have two narrower

resonances (Figure S51, SI). These observations are indic-

ative of dynamic behavior in solution. The signals due to

the methylene protons from the -CH₂O moiety obtained

in CDCl₃at room temperature are more informative. For

example, for 4a, three signals of different intensities are

observed between 4.05 and 4.24 ppm with J_H-Hcouplings

of 6.1–6.4 Hz (Figure 1). This observation demonstrates

the presence of at least three isomers in solution in a

3.2/0.8/0.1 ratio. Two major signals can be attributed to

the known pyramidal inversion of sulfur atoms occurring

1

The H and ¹³C{¹H} NMR spectra of 1a–8a in CDCl₃

or DMSO-d₆are generally consistent with the structure

presented in Scheme 2. For 1a and 2a, DMSO-d₆was the

most suitable solvent, as these complexes were poorly sol-

uble in other solvents. The formation of 16-membered

dinuclear complexes is supported by an X-ray study of 4a

1

(vide infra). In the H NMR spectra, the resonances in

the range of 3.6–4.3 ppm are attributable to the four

hydrogens of the -CH₂OCH₂- group and are at a lower

field than the corresponding resonances of the free

ligands. Signals from eight hydrogens in the -SCH₂- units

SUSLOV ET AL.

15 of 27

FIGURE 1 ¹H NMR of 4a in CDCl₃at room temperature

FIGURE 2 Plausible invertomers and

isomers of 1a–8a (ΔU₀– zero point energy from

DFT calculation for 1a)

in palladium oxadithioether complexes.^[69,70]As shown

in Figure 2, two diastereoisomers (invertomers) can exist

in solution, which differ in the orientation of the S-R

groups. The S-R groups are cis-arranged in the meso-

invertomer, whereas they are trans-arranged in the

d,l-invertomer. The presence of an additional isomer

may be associated with the formation of a mononuclear

Pd (II) complex chelated by an eight-membered

ring (Figure 2). Similar mononuclear complexes

and have been evidenced by X-ray studies.^[63,70]ESI-MS

analysis (positive mode, MeCN) of 1a–8a demonstrated

the molecular peaks of complex cations, which can be

attributed to mono- ([Pd(L)Cl]⁺) or dicationic

([Pd₂(L)₂Cl₂]²⁺

)

species, for example, 4a m/

z = 364.98 Da. For complexes 5a and 7a, ESI-MS analysis

also showed minor peaks of dimers with one chorine

dissociated ([Pd₂(L)₂Cl₃]⁺) and coordination oligomers

[Pd₃(L)₂Cl₅]⁺. Thus, the formation of di- or mononuclear

complexes in solution was not clear from ESI-MS

experiments.

(cis-[PdCl₂(1-oxa-4,7-dithiacyclononane)]

and

cis-

[PdCl₂{(PhSCH₂SiMe₂)₂O}]) are known in the literature

16 of 27

SUSLOV ET AL.

Therefore, we performed density functional

theory (DFT) calculations on the BP86/def2-TZVP_Pd,S,Cl

vibration band in the OCH₂groups decreases by 5–

10 cm^ꢀ1and appears as a shoulder on the vibration band

from the SCH₂groups, increasing 2–3 times in intensity

compared to free ligand. For example, upon coordination

to palladium, the intensity ratio I(δ_{HCH, scissoring})/I(ν_{as C–}

_O–C) increases 1.8, 2.5, 2.3, 2.7, and 3.5 times in L1, L2,

L3, L5, and L7, respectively. Bands of mixed wagging

and twisting vibrations of methylene groups at various

substituents are observed in the spectra at 1100–

1400 cm^ꢀ1. In this case, the bands, which are primarily

attributable to the vibrations of the SCH₂groups,

increase in intensity upon coordination to Pd. For exam-

ple, for L1, the 1190 cm^ꢀ1band appears in the spectrum

as a shoulder at 1200 cm^ꢀ1, but an increase in its inten-

sity is observed in the spectrum of complex 1a. Thus,

twisting vibrations in SCH₂groups make a greater contri-

bution to the 1190 cm^ꢀ1band.

/

def2-SVP_C,H,Olevel regarding the most plausible isomers

(meso-, d,l-invertomers) for mononuclear species related

to 1a and two conformational isomers of dinuclear 1a.

The energy gap between dinuclear 1a and its mononu-

clear version is greater than that between the meso- and

d,l-isomers (see Table S4, SI). The energy difference

between di- and mononuclear complexes calculated with

the DFT method is approximately 7 kcal/mol (Figure 2).

The energetic (Δ_rU₀) gap between the two optimized iso-

mers of 1a accounts for ≈1.7 kcal/mol. These calculations

confirm the coexistence of the two dinuclear isomers in

solution as a consequence of interconversion equilibrium.

The formation of monomeric cis-chelated palladium

complexes is energetically less favored, and such species

probably exist in negligible amounts in solution.

For oxadithioether ligands L1–L8 and complexes

1a–8a, IR spectroscopy enables the confirmation of

successful complex formation, as well as helping to eluci-

date their structural and spectroscopic features. In the

range of 2850–2960 cm^ꢀ1, stretching vibrations of CꢀH

bonds from CH₃, CH₂, and CH groups were observed; for

L1–L8, there are no deviations from the generally

accepted frequency values. However, upon coordination

to palladium, the bands of the stretching vibrations of

CꢀH bonds in groups at S are shifted toward higher fre-

quencies. Moreover, this effect weakens with an increase

in the length of the substituent chain and is practically

not observed for the groups located in the γ-position rela-

tive to the sulfur atom. For example, the band at

≈2960 cm^ꢀ1is caused by antisymmetric stretching vibra-

tions of CꢀH bonds in the methyl group in most organic

compounds. However, in complex 1a, this band splits

into two bands and shifts by 40 cm^ꢀ1(average value,

3009 and 2986 cm^ꢀ1). In complexes 2a and 4a, where the

methyl group is in the β-position, the band increases to

≈2970 cm^ꢀ1on average. A similar trend for the vibra-

tions of methylene groups was observed for complex 8a.

In L8, the antisymmetric CꢀH stretching vibrations of

the CH₂groups of the benzyl moiety appear as a band at

2950 cm^ꢀ1and do not overlap with bands from the S-

CH₂-CH₂-O-fragment. In the IR spectrum of 8a, the

frequency of this band increases to 2975 cm^ꢀ1. For L1,

characteristic bands at 1436 and 1320 cm^ꢀ1should be

noted, corresponding to bending antisymmetric and sym-

metric vibrations in S-CH₃, respectively.^[71]Upon coordi-

nation to Pd, the δ_as(C-H from S-CH₃) band is shifted up

to ≈1470 cm^ꢀ1and splits, while δ_sdoes not change its

position in the spectrum. In the IR spectra of L1–L8, the

bands of scissoring vibrations in the OCH₂groups

(≈1427 cm^ꢀ1) and SCH₂groups (≈1405 cm^ꢀ1) are also

observable. In the spectra of complexes 1a–8a, the

The IR spectrum of L1 contains an intense band of

antisymmetric stretching vibrations of CꢀOꢀC bonds at

1110 cm^ꢀ1, with a full width at half maximum (FWHM)

of 123 cm^ꢀ1. The large width of this line is due to the

presence of a significant number of conformational iso-

mers in equilibrium in L1. Upon coordination to palla-

dium, the geometric structure of L1 is stabilized, and as a

result, this band is narrowed by a factor of 2.5. Notably,

the FWHM of the 1110 cm^ꢀ1bands in the other ligands

is considerably narrower and decreases from 58 cm^ꢀ1for

L2 to 48 cm^ꢀ1for L8. In complexes 1a, 3a–8a, the

FWHM of the corresponding band decreases insignifi-

cantly (Δ (FWHM) = 2–12 cm^ꢀ1). An exception is 2a, for

which the narrowest ν_as(CꢀOꢀC) band with an FWHM

of 33 cm^ꢀ1was observed. This result may indicate the

stabilization of a small number of conformers. For com-

plex 4a, this band is split into two bands (the FWHM is

43 cm^ꢀ1), which indicates the formation of two types of

isomers (in the solid). In addition, splitting of the

ν_s(CꢀOꢀC) band was observed in the IR spectra of com-

plexes 1a–8a. It should be noted that the peak of

ν_as(CꢀOꢀC) in complexes 1a, 2a, 3a, 5a, and 7a shifts as

the substituent lengthens from 1125 cm^ꢀ1(for 1a) to

1003 cm^ꢀ1(for 7a). Weak bands from antisymmetric and

symmetric stretching vibrations of CꢀSꢀC bonds were

observed in the IR spectra of L1–L8 at 600–700 cm^ꢀ1

.

Moreover, the heavier the substituents on sulfur were,

the weaker the intensity of these bands was. The shift of

these bands to lower frequencies in the IR spectra

of complexes 1a–8a by 10–50 cm^ꢀ1confirms the coordi-

nation of ligands to palladium through sulfur atoms. This

shift was most clearly recorded for L1 (ν_as(CꢀSꢀC)

= 700 cm^ꢀ1and ν_s(CꢀSꢀC) = 660 cm^ꢀ1

)

and 1a

(655 and 640, respectively). Notably, for complex 4a,

splitting of the ν_as(CꢀSꢀC) and ν_s(C ꢀ S ꢀ C) bands in

the IR spectrum was observed (ν_as= 686, 665 cm^ꢀ1and

SUSLOV ET AL.

17 of 27

ν_s= 632, 619 cm^ꢀ1), which indicates the formation of at

least two types of isomers.

Surprisingly, the ligand 1,5-bis(tert-butylthio)pentane,

which is comparable to ligand L4, adopted an elongated

boat-like conformation when coordinated to palla-

dium.^[73]Most likely, a chair-like conformation is pre-

ferred due to a weak dative Pd1ꢃꢃꢃO1 bond in 4a. In the

crystal structure of 4a, the oxygen atom of L4 is oriented

toward palladium and lies inside the coordination mac-

rocycle at a Pd1ꢃꢃꢃO1 distance of 3.011 Å. The sum of the

van der Waals radii of the atoms in question is 3.10 Å.

3.3 | X-ray crystal structure of 4a

Single crystals of 4a suitable for X-ray crystallography

were obtained by slow vapor diffusion of diethyl ether

into 1,2-dichloroethane solutions of the complex.

Complex 4a contains two four-coordinate palladium

(II) centers.

The solid-state molecular structure of 4a is depicted

in Figure 3 with selected interatomic distances and

angles listed in the figure caption. The Pd–S bond lengths

of 2.331 and 2.325 Å are similar to those reported for

3.4 | Synthesis of cationic palladium

(II) Acetylacetonate complexes

The synthesis of complexes 1b–8b was achieved by

trans-[Pd₂Cl₄{μ-^tBuS (CH₂)₅S^tBu}₂] (d_Pd-S,

= 2.33 Å)

reacting

bis(acetonitrile)(acetylacetonate)palladium

av.

but longer than cis-[PdCl₂(1-oxa-4,7-dithiacyclononane)],

cis-[PdCl₂{(PhSCH₂SiMe₂)₂O}], and cis-[PdCl₂([9]aneS₃)],

with Pd–S bond lengths of 2.26–2.31 Å.^[63,70,72]The aver-

age Pd–Cl bond length (2.301 Å) lies in the usual range

found for four-coordinate Pd (II) complexes.^[1]

(II) tetrafluoroborate with one equivalent of L1–L8 in

dichloromethane, which led to the formation of [Pd(acac)

(L)][BF₄] (1b–8b), as depicted in Scheme 2. The new

complexes were fully characterized by NMR and FTIR

spectroscopy, ESI-MS and elemental analysis.

The two trans-arranged Cl atoms form a Cl1-Pd1-Cl2

angle of 179.347(19), and the angle between the sulfur

atoms of S1-Pd1-S2 of 173.760(16) indicates slight defor-

mation of the square planar geometry for palladium. The

16-member ring has a “parallelogram shape” when

viewed along the Cl–Pd bond with sides formed by the

extended S-(CH₂)₂O(CH₂)₂-S chains and the trans S-Pd-S

linkages. From an overhead point of view, the

16-membered ring adopts a chair-like conformation.

In contrast to 1a–8a, these complexes are most likely

mononuclear. In our opinion, this is due to destabiliza-

tion of the dinuclear 16-member ring structure forced by

the acac ligand cis-structure. DFT calculations regarding

the most plausible conformational isomers for the cation

of 1b (1b+) and dinuclear dication of 1b showed an

energy gap of ≈15 kcal/mol (Figure 4). Notably, the

geometrical conformers of [Pd(acac)(L)]BF₄can exist in

two exo- or endo-type conformations (Figure 4). In the

FIGURE 3 An ORTEP drawing of 4a with

thermal ellipsoids drawn at the 50% probability

level. Hydrogen atoms are omitted for clarity.

Details of the structure refinement are given in

Table S1, SI. Selected bond distances (Å) and

angles (^ꢂ): Pd1—S1 = 2.3253(4), Pd1—

S2 = 2.3311(5), Pd1—Cl1 = 2.3005(4), Pd1—

Cl2 = 2.3011(5); ∠Cl1—Pd1—S1 = 86.286(16),

∠Cl2—Pd1—S2 = 84.683(18), ∠S1—Pd1—

S2 = 173.760(16), ∠Cl1—Pd1—Cl2 = 179.347

(19)

18 of 27

SUSLOV ET AL.

FIGURE 4 Plausible invertomers

and isomers for cations of 1b–8b in

solution (ΔU₀– zero point energy from

DFT calculation for cations of 1b)

endocomplexes, an oxygen atom on the ligand is directed

toward the inner side of the central metal. The oxygen

atom of the endocomplex plays the role of a weak elec-

tron donor group to the central Pd (II) metal.^[74]As a

result, the DFT-calculated structures for 1b+ show that

the more stable conformers are endo-ones. The oxygen

atom in endo-1b+ lies above the coordination plane with

a (PdꢃꢃꢃO) distance of 2.991–3.101 Å. The average zero

point energy difference between endo- and exo-1a + -

(Figure 4) calculated with the DFT-BP86 method is

approximately 2.5 kcal/mol (see Table S4, SI). The forma-

tion of mononuclear complexes was also evident from

HPLC analysis of the complex solutions (MeCN). The

retention times (R_t) for 1b–8b were 1.70–1.95 min; for

dinuclear complexes 1a–8a, R_t= 2.20–2.65 min.

distribution. For example, when the ligand with the Me-S

group is used, the ratio of the integrals from CH-acac pro-

tons in the ¹H NMR spectrum (CDCl₃, 5.56 and

5.53 ppm) was 0.5; for 7b (n-hexyl-S group), the integral

ratio of the corresponding signals (5.60 and 5.56 ppm)

1

was 4.0. In general, the signals in the H NMR spectra

(at 25^ꢂC) are relatively broad, which is indicative of a

1

dynamic exchange process. The H,¹H NOESY spectra of

1b and 5b exhibit an exchange of cross-peaks arising

from the dynamic exchange between the -CH₂O- and

-CH₂S- groups of the chelated oxadithioether ligands

(Figure S52, SI). This result clearly indicates the presence

and interconversion of isomers in solution, which

differ in the orientation of the S–R groups, as well as in

structures involving a weak apical PdꢃꢃꢃO contact.

Since the small energy changes in solvent incorpora-

tion (especially coordinating forces) or crystal packing

forces may switch the endodentate and exodentate coor-

dinations of the Pd (II) metal cation with the ligands,^[74]

four isomeric complexes can be formed from 1b–8b in

solution. The ¹H and ¹³C{¹H} NMR spectra of 1b–8b

in CDCl₃or CD₃CN are consistent with the presence of

isomers (Figure 4) in a solution. The spectra of all com-

plexes ligated with the L1–L8 ligands show the presence

of two or more structures. In particular, resonances from

the Me-S fragment in the ¹H NMR spectrum of 1b appear

as four broad signals (2.37 (12%), 2.31 (19%), 2.24 (48%),

2.18 (21%) ppm). In the NMR spectra of 1b–8b, two or

three signals can be easily distinguished from the CH-

and CH₃-protons of acetylacetonate ligands.

To further investigate the dynamic behavior of the

oxadithioether ligands, we performed variable tempera-

ture ¹H NMR experiments with cationic complex 2b.

1

Figure 5a presents the region of the H NMR spectra in

CD₃CN or CDCl₃from ꢀ50^ꢂC to 70^ꢂC. In CD₃CN, the

fast exchange limit is almost reached at 70^ꢂC. All signals

in the spectrum decoalesce into two or more signals at

lower temperatures. The same trend was observed in the

¹³C NMR spectra of 2b (Figure 5b). Two signals from

-CH₂O-, -CH₂S-, and acac groups are apparent in the ¹³C

NMR spectrum of 2b at 25^ꢂC, with coalescence occurring

at ≈70^ꢂC in CD₃CN. The free energy of activation esti-

mated according to the equation ΔG^#= RT_c[22.96 + ln

(T_c/δ_ν)]^[10,75]for the dynamic fluxional behavior of 2b

from NMR at coalescence temperatures suggests a barrier

of approximately 16 kcal/mol. An activation energy ΔG^#

of 16.9 kcal/mol was determined for the process of pyra-

midal inversion of sulfur atoms occurring at the chelate

It was concluded from ¹H and ¹³C{¹H} NMR spectros-

copy that the length and structure of the alkyl group at

the sulfur atom of the ligand influence the isomer

SUSLOV ET AL.

19 of 27

FIGURE 5 NMR spectra of 2b at various

temperatures: ¹H [CD₃CN: 1–343 K, 2–298 K;

CDCl₃: 3–293 K, 4–283 K, 5–263 K, 6–253 K,

7–243 K, 8–233 K, 9–223 K] (a);¹³C{¹H} [CD₃CN:

1–298 K, 2–343 K] (b); and ¹H,¹H NOESY and

COSY [CDCl₃, 263 K] (c)

20 of 27

SUSLOV ET AL.

complex cis-[PdCl₂(MeSCH₂CH₂SMe)].^[69]The H NMR

spectra of 2b recorded in CDCl₃were notably compli-

cated (Figure 5). To elucidate the structural features of

the complex, correlation spectroscopy (COSY), nuclear

Overhauser effect spectroscopy (NOESY), and heter-

onuclear single-quantum correlation spectroscopy

(HSQC) 2D procedures were used in addition to analysis

of the one-dimensional ¹H and ¹³C NMR spectra.

exo-, meso- and d,l- forms overlap, further analysis of the

peaks is precluded.

1

Complexes 1b–8b were characterized by IR spec-

troscopy (see Section 2). The spectra contain all the

vibration bands of the fragments of the L1–L8 ligands

(vide supra), as well as intense bands of stretching

vibrations of C=O and C=C bonds of the ace-

tylacetonate chelate at 1560 and 1520 cm^ꢀ1. In addi-

tion, the spectra show two bands at 693 and 636 cm^ꢀ1

from antisymmetric and symmetric stretching vibra-

tions of CꢀSꢀC bonds, respectively. Moreover, the

position of these bands is unchanged in all complexes.

This evidences the formation of identical structures in

complexes 1b–8b. The 1150–1000 cm^ꢀ1region is uni-

nformative, since it is almost completely overlapped by

intense bands of antisymmetric stretching vibrations of

the [BF₄]^ꢀanion. Therefore, further analysis to deter-

mine populations of the two forms or more isomeric

forms is precluded in the solid phase. Notably, in all

spectra of the complexes at 780–790 cm^ꢀ1, there is a

band of symmetric stretching vibrations of the [BF₄]^ꢀ

anion, which is forbidden in the IR spectrum of an

ideal tetrahedron. This result indicates a distortion of

the ideal tetrahedral geometry of the anion molecule

caused by the interaction of the latter with the

fragments of the cation.

1

Analysis of the H NMR spectrum of 2b showed the

presence of four isomeric complexes. For example,

resonances from the Me fragment appear as four triplets

(1.54 (11%), 1.50 (19%), 1.47 (34%), and 1.41 (36%) ppm).

The complication of the spectral pattern in the aliphatic

region is also related to the restriction of the mobility of

oxadithioether units in the rigid spatial structure of 2b.

A similar phenomenon was reported^[7]for palladium

(II) complexes with benzothiacrown ethers as ligands.

Restriction of the ligand mobility in 2b results in

splitting of the proton signals of the oxadithioether

methylene groups. Chemical shifts for the axial and

equatorial protons in the spectrum of 2b were inter-

preted using quantum-chemical calculation of the

nitrobenzodithiacrown ether palladium (II) complexes

with similar structural SOS patterns.^[7]Figure 5 shows

fragments of the NOESY and COSY spectra of 2b,

where the cross-peaks correspond to coupling of the

methylene-group geminal and methylene-methyl-group

protons from four different isomers. In contrast to the

1

results obtained for 1b and 5b in CD₃CN, in the H,¹H

3.5 | X-ray crystal structure of 4b

NOESY spectra of 2b (ꢀ10^ꢂC, CDCl₃), there are no

exchange cross-peaks arising from the dynamic exchange

between -CH₂O- and -CH₂S- groups. This result suggests

that interconversions of the isomers, which differ in the

orientation of the weak apical PdꢃꢃꢃO contact, are slow

on the NMR timescale in CDCl₃at ꢀ10^ꢂC. An interpre-

tation of the major isomer peaks in the aliphatic

region suggests that these represent invertomers of an

endodentate conformation of the coordinated 6-oxa-

3,9-dithiaundecane. The resonances at 4.38 (m), 4.10

(dt) and 3.92 (t), 3.73 (dt) ppm are assigned as the two

axial and two equatorial hydrogens of the -CH₂O-group

from two invertomers of the endo-SOS-chelate and are

shifted downfield compared with the peak of the free

ligand (3.61 ppm). The resonances from 4.0 to 4.9 ppm

are assigned as invertomers of an exodentate conforma-

Single crystals of 4b suitable for X-ray crystallography

were obtained by slow vapor diffusion of diethyl ether

into 1,2-dichloroethane solutions of the complex.

Figure 6 shows the structure of 4b. Selected bond

lengths and angles are given in the figure captions.

Ligand L4 assumes a facial coordination mode in 4b.

Complex 4b has a distorted square planar geometry for

palladium, shown by the ∠O3—Pd1—O2 and ∠S1—

Pd1—S2 bond angles of 93.2(6)^ꢂand 91.23(18)^ꢂ, respec-

tively. The average Pd–S bond distance of 2.275 Å is

comparable with those found in other Pd (II) complexes

of macrocyclic thioethers.^[1,63,70]As in the case of 4a in

the crystal structure of 4b, the oxygen atom of L4 is ori-

ented toward palladium at a PdꢃꢃꢃO distance of 2.893 Å,

indicating weak dative PdꢃꢃꢃO bond formation. In addi-

tion, short contacts between the fluorine atoms of

[BF₄]^ꢀand the hydrogens of the methylene groups

(FꢃꢃꢃH-C, 2.449–2.661 Å) are observed in the crystallo-

graphic packing of 4b, presumably forming minor

C–HꢃꢃꢃF hydrogen bonds. Consequently, distortion of the

idealized tetrahedral geometry of the anion [BF₄]^ꢀ

(e.g., ∠F4—B1—F3 = 106(3)^ꢂ) leads to the appearance

of symmetric stretching vibration at 789 cm^ꢀ1in the IR

1

tion of L2. Notably, the signals observed in the H NMR

spectra of 2b from one of the major isomers (see

resonances at 4.19, 3.92, and 2.69 ppm, Figure 5)

broaden when the temperature drops below 263 K.

The resonances at 2.69 (dq) and 2.61 (dq) ppm are

assigned as the two equatorial hydrogens of the

-SCH₂CH₃-group from two major invertomers. As

several peaks of the -CH₂SCH₂-group attributed to endo-,

SUSLOV ET AL.

21 of 27

SCHEME 3

free cationic Pd-catalyzed systems with O^O-chelating

ligands (O^O = β-diketonates or carboxylates) activated

with Lewis acid such as BF₃ꢃOEt₂have shown promising

results for polymerization of norbornene and its deri-

vates.^{[36,38,39,80,81]}The main results are listed in Tables 1

and 2. All 1a–8a complexes produce polynorbornene,

showing moderate to high activities on the order of

1.5ꢃ10⁵–1.4ꢃ10⁷g_PNBmol_Pd

h

^ꢀ1. Table 1 shows that for

ꢀ1

oxadithioether-ligated complexes, the catalytic productiv-

ity under the same conditions decreased in the following

order: 6a, 5a, 3a > 4a > 1a, 8a > 2a, 7a. This can be

attributed to the influence of electronic or steric proper-

ties of oxadithioether ligands and to differences in the

reactivity of these ligands with AlⁱBu₂Cl if they dissociate.

Upon activation, oxadithioether ligands can be lost to

give a “naked” Pd as the active species. Hence, more

weakly bound ligands that can be removed faster will

lead to the more active palladium “naked” species more

quickly.^[82,83]In blank experiments, no activity was

observed with any of the complexes in the absence of the

cocatalyst or with AlⁱBu₂Cl alone. The use of BF₃ꢃOEt₂as

a cocatalyst to activate 1a–8a led to low catalytic activity.

In contrast to the results for 1a–8a, catalyst systems

(1b–8b)/BF₃ꢃOEt₂generally showed moderate polymeri-

zation activities (Table 2) of 1.2ꢃ10⁵–8.0ꢃ10⁵g_PNB(mol

FIGURE 6 An ORTEP drawing of 4b with thermal ellipsoids

drawn at the 50% probability level. Hydrogen atoms and BF₄

counterion are omitted for clarity. Details of the structure

refinement are given in Table S1, SI. Selected bond distances (Å)

and angles (^ꢂ): Pd1—O3 = 2.018(13), Pd1—O2 = 2.018(13), Pd1—

S1 = 2.278(5), Pd1—S2 = 2.273(5); ∠O2—Pd1—O3 = 93.2(6),

∠S1—Pd1—S2 = 91.23(18), ∠O2—Pd1—S2 = 178.0(5), ∠O3—

Pd1—S1 = 176.6(4)

spectrum of 4b, which is forbidden in the infrared

absorption spectrum.

3.6 | Catalytic studies

Pd)^ꢀ1^ꢀ1. The yield, as well as the catalyst activity, also

h

Bicyclo[2,2,1]hept-2-ene (norbornene, NB) can be poly-

merized in three different ways: ring opening metathesis

polymerization, cationic or radical polymerization, and

vinyl/addition polymerization. Addition polynorbornene

(PNB) has received considerable attention due to its

dielectric and mechanical properties for technical appli-

cation as an interlevel dielectric in microelectronics

applications.^[76–79]Catalyst systems based on palladium

and nickel complexes in different oxidation states exhibit

high activity (usually in the range of 10⁵–10⁷g_NBmol^ꢀ1

depends significantly on the reaction parameters applied,

such as the cocatalyst/catalyst ratio, monomer/catalyst

ratio, and reaction temperature (Table S5 and Figures S1

and S2, SI). Table 2 shows that the catalytic productivity

for n-alkyl-oxadithioether-ligated cis-complexes under

the same conditions decreased in the following order: 5b,

7b > 3b > 1b ꢄ 2b. The most active complex 5b was

chosen as the precatalyst for the study of the polymeriza-

tion in detail. A linear relation between activity and the

initial molar ratio of norbornene to 5b of up to [NB]₀/

[Pd]₀of 5000 was found (Figure S2, SI). A further

increase of [NB]₀/[Pd]₀lowered the activity. Such con-

centration effect of palladium precatalyst was reported

for norbornene polymerization by C. Janiak et al^[84]and

may be explained by impurities which are contained in

the monomer and eventually decrease the number of

active centers. Variation of the ratio of BF₃ꢃOEt₂to 5b

showed considerable effect on the catalytic activities

(Table 2, Entries 9–12). When the [B]/[Pd] ratio was

increased, the catalytic ability of 5b first increased rapidly

cat h^ꢀ1) in the addition polymerization of NB.^[76–79]

A

variety of palladium complexes have been reported to be

active for the polymerization of norbornene,^[76,79]but the

application of oxadithioether-chelated palladium com-

plexes in this reaction is not known to date. We studied

the polymerization of norbornene (Scheme 3) with

chlorido palladium complexes (1a–8a) in the presence of

typical Ziegler–Natta alkylating cocatalyst (AlⁱBu₂Cl).

Cationic acetylacetonate complexes (1b–8b) were acti-

vated with BF₃ꢃOEt₂. It is known that aluminum alkyl-

22 of 27

SUSLOV ET AL.

TABLE 1 Polymerization of

norbornene by (1a–8a)/nAlⁱBu₂Cl

Entry^a

Complex (R)

1a (Me)

[NB]₀: [Pd]₀

5000

[Cocat.]₀: [Pd]₀

Y/%^b

27

16

62

48

62

73

22

5

TON^c

1400

800

A^d

1

75

260

150

580

450

590

690

2

2a (Et)

3a (ⁿPr)

4a (ⁱPr)

5a (ⁿBu)

6a (ⁱBu)

5000

3

5000

75

3100

2400

3100

3700

11,200

26,800

75,900

800

4

5000

75

5

5000

75

6

5000

75

7^e

8^f

9^g

10

11

12^h

13^h

50,000

500,000

5000

250

2500

75

2110

5060

14,290

160

15

17

20

<0.1

2

7a (n-hexyl)

8a (benzyl)

4a (ⁱPr)

5000

75

1000

2

190

5000

50

0.4

20

6a (ⁱBu)

5000

50

90

^aReaction conditions: t = 25^ꢂС, 0.02 mol.% Pd, n_Pd= 4.9 μmol, dichloromethane, V₀= 9 ml, reaction

time—0.5 h.

^bYield of PNB.

^cTON in (mol NB) (mol Pd)^ꢀ1

.

^dAverage activity of the catalyst in (kg NB) (mol Pd h)^ꢀ1

^e0.002 mol.% Pd, n_Pd= 0.49 μmol.

.

^f2 ppm (mol.) Pd, n_Pd= 0.05 μmol.

^g2 ppm (mol.) Pd, n_Pd= 0.05 μmol, t = 75^ꢂС.

^hCocatalyst—BF₃ꢃOEt₂.

and then increases smoothly (also see Figure S1 (SI) for

the same trend with 1b as precatalyst). It was found that

the activity of 5b increased with increasing temperature

from 25^ꢂC to 100^ꢂC (Table 2, Entries 14, 18–20). The

highest activity was found at 100^ꢂC, indicating that

the active species is stable at high temperature. Along

with an increase of [NB]₀/[Pd]₀ratio and reaction time

at 100^ꢂC resulted in high TON of 44,000 with the

Notably, complexes 2b and 4b activated with boron

trifluoride etherate showed low activity in the polymeri-

zation of NB. Proposed mechanism of the formation of

the active species is shown in Figure 7. Beginning with

the BF₃adduct, the first step of the catalytic reaction

involves the transformation of κ²-O,O-acetylacetonate

to

a π-complex with a γ-bonded acetylacetonate

ligand.^[39,86–88]In the next step, insertion of the coordi-

nated NB into the Pd–C bond occurs (Figure 7). The reac-

tion of 1b–7b with BF₃ꢃOEt₂in the presence of hex-1-ene

as a model substrate was monitored by FTIR (see

Figures S84–S91, SI). The IR spectrum of the reaction

mixture 6b/20(hex-1-ene)/3BF₃ꢃOEt₂exhibits a decrease

in the intensity of the absorbance band at 1520 cm^ꢀ1

with the reaction time (Figure S91, SI). The band at

1520 cm^ꢀ1is due to stretching vibrations of the C=O and

C=C bonds in the chelate-bonded acac group.^[89]Upon

the addition of BF₃ꢃOEt₂to a solution of 6b and hex-

1-ene, new bands appear at 1555 and 580 cm^ꢀ1. The band

at 1555 cm^ꢀ1characterizes acac ligated with boron

trifluoride (C=OꢃBF₃).^[90]The band at 580 cm^ꢀ1can be

assigned to the stretching vibrations of the Pd–C bond.^[91]

When the reaction was performed using 4b/20(hex-

1-ene)/3BF₃ꢃOEt_2,similar results were obtained but with

substantially slower acac-group transformation from the

O^O-bonded to C-bonded form (Figure S87, SI). For

activity up to 2.7ꢃ10⁶g_PNB(mol Pd)^ꢀ1

h

^ꢀ1. Solvent

dependence of the polymer yields was found for catalyst

system 5b/nBF₃ꢃOEt₂. No activity was observed in polar

coordinating solvents such as acetonitrile and N,N-

dimethylformamide (Table 2, Entries 15 and 16), while in

weakly coordinating solvents (Table 2, Entries 14 and 17)

the catalyst activity was practically the same. The high-

temperature stability of the catalyst system 5b/nBF₃ꢃOEt₂

prompted us to investigate whether it also had high

activities toward polymerization of polar NB derivative

(5-methoxycarbonylnorbornene), but almost no polymer

of NB-COOCH₃was obtained. This is common for ester-

functionalized norbornene derivatives,^[77]for which the

carbonyl oxygen atom competes with the vinyl double

bond for the coordination. Thus, in contrast to the

known steric hindered phosphine-ligated palladium

catalysts,^[36,77,85]nonbulky n-alkyl-oxadithioether-ligated

palladium complexes cannot inhibit this chelation.

SUSLOV ET AL.

23 of 27

TABLE 2 Polymerization of norbornene by (1b–8b)/nBF₃ꢃOEt₂

Entry^a

Complex (R)

1b (Me)

[NB]₀: [Pd]₀

2000

[Cocat.]₀: [Pd]₀

t/ ^ꢂС

25

τ^b/h

0.5

1.0

1.5

0.5

1.5

5.0

0.5

Solvent

CH₂Cl₂

DCE^f

Y/%^c

63

5

TON^d

1260

100

A^e

1

30

10

30

70

100

70

50

240

20

2

2b (Et)

2000

25

3

3b (ⁿPr)

4b (ⁱPr)

2000

25

73

2

1460

40

280

10

4

2000

25

5

5b (ⁿBu)

6b (ⁱBu)

7b (n-hexyl)

8b (benzyl)

5b (ⁿBu)

4b (ⁱPr)

2000

25

89

80

79

41

24

57

93

96

7

1780

1600

1560

820

340

300

290

150

225

540

880

910

210

600

–

6

2000

25

7

2000

25

8

2000

25

9

5000

25

1200

2850

4650

4810

1100

3150

–

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24^h

25ⁱ

26ⁱ

5000

25

5000

25

5000

25

15,000

30,000

50,000

500

25

75

21

0

75

MeCN^g

DMF^g

75

0

–

g

75

CH₃NO₂

DCE^f

15

47

70

91

42

29

88

0

2250

7050

10,500

13,650

12,500

14,400

44,000

–

430

670

660

2580

2370

2730

2760

–

75

100

25

5000

CH₂Cl₂

20

19

1000

930

200

180

6b (ⁱBu)

5000

25

^aReaction conditions: n_NB= 24.6 mmol, V₀= 9 ml.

^bReaction time.

^cYield of PNB.

^dTON in (mol NB) (mol Pd)^ꢀ1

.

^eAverage activity of the catalyst in (kg NB) (mol Pd h)^ꢀ1

.

^fSolvent—1,2-dichloroethane.

^g80/20 v/v mixture of the solvent/1,2-dichloroethane was used.

^h5-methoxycarbonylnorbornene was used as monomer (exo/endo = 53/47).

ⁱCocatalyst—AlⁱBu₂Cl.

example, after 3 min, only 14% of the initial amount of

4b transformed, whereas more than 44% of the O^O-

bonded acac groups are transformed for 6b. For 1b, 2b,

3b, 5b, and 7b, the same trends in the FTIR monitoring

results were observed (Figures S84–S91, SI). We presume

that these observations indicate that the nature of the

oxadithioether ligand influences the acac-group activa-

tion step. Additional details of the activation hypothesis

were obtained from NMR (¹H and ¹⁹F) investigations (see

for spectroscopic details Figures S54–S59 and Tables S6–

S7, SI). The reaction of 4b and 6b with BF₃ꢃOEt₂(5 equiv)

in CDCl₃in an NMR tube at room temperature led to the

transformation of κ²-O,O-acetylacetonate ligand within

6 min (the conversion was 39% for 4b and 68% for 6b

1

based on H NMR data for CH-acac at 5.0–5.7 ppm) and

appearance of a new signal at 6.0 ppm attributed to

BF₂(acac). New signals from BF₄anion coordination

were also detected by ¹⁹F NMR (ꢀ150.83, ꢀ149.57 ppm),

BF₂(acac) (ꢀ138.71 ppm), and an unidentified signal that

was observed at ꢀ153.87 ppm. No Pd-black was observed.

The NMR data were assigned to “L_nPd(FꢃBF₃)” species

and BF₂(acac) by comparison with values in the

24 of 27

SUSLOV ET AL.

4 | CONCLUSIONS

Palladium complexes trans-[PdCl₂(μ-L)]₂and [Pd(acac)

(L)][BF₄] (L = RS (CH₂)₂O(CH₂)₂SR, R = Me, Et, ⁿPr,

i

ⁱPr, ⁿBu, Bu, n-hexyl, benzyl) were synthesized and

characterized by multinuclear NMR spectroscopy, FTIR

spectroscopy, and mass spectrometry. Two palladium

(II) complexes were characterized by X-ray crystallogra-

phy. Variable temperature NMR spectroscopic studies

and DFT calculations confirmed dynamic bonding

of the oxadithioether ligands, which was consistent

with the presence of diastereoisomers that differ in the

orientation of the S-R groups along with both

endodentate and exodentate bonding modes in solution.

The flexibility of oxadithioether ligands expressed as dif-

ferent conformations in different complexes parallels the

experience with the ligand series described in this report.

The catalytic potential of trans-[PdCl₂(μ-L)]₂and [Pd

(acac)(L)][BF₄] was demonstrated in the polymerization

of norbornene.

FIGURE 7 Proposed mechanism of the formation of the active

species using (1b–8b)/nBF₃ꢃOEt₂. The anion is omitted for clarity

literature.^[92–95]Observation of the signals from BF₂(acac)

suggests the formation of dicationic palladium species

(see Figure S53, SI) and, in our opinion, presents a cata-

lyst deactivation pathway that occurs in the catalyst sys-

tems under study. It should be noted that the significant

decrease in activity of the monuclear complexes com-

pared with the dinuclear complexes (e.g., 4a, 6a vs 4b,

and 6b) can also be explained by metal–metal coopera-

tivity effect, which was reported by C. Chen et al^[96–98]in

ethylene polymerization by dinuclear α-diimine Ni

(II) and Pd (II) complexes.

ELECTRONIC SUPPLEMENTARY

INFORMATION AVAILABLE

XRD, NMR, FTIR, ESI-MS, EI-MS spectral data, DFT

calculations and NB polymerization results.

ACKNOWLEDGMENTS

The reported study was funded by RFBR, project number

20-33-70139. The studies were performed utilizing

equipment from the Baikal Analytical Center of

Collective Use SB RAS (http://ckp-rf.ru/ckp/3050/), the

Center for Collective Use of Analytical Equipment of

Irkutsk State University (http://ckp-rf.ru/ckp/3264/),

and the Shared Research Facilities for Physical and

Chemical Ultramicroanalysis LIN SB RAS. We thank

Dr. A.V. Kuzmin for ESI-MS measurements.

The resulting polynorbornenes were insoluble in

common solvents, such as benzene, chloroform, methy-

lene

chloride,

THF,

toluene,

and

1,2,4-trichlorobenzene. Therefore, we cannot measure

the molecular weights of the polymers by GPC. Insolu-

bility of addition PNBs is frequently observed and con-

sidered indicative of high stereoregularity or the

existence of

a

cross-linking structure by the

C7-linkage, since intramolecular σ-bond metathesis

leads to a rigid helical structure of the PNB, which

strongly affects its solubility.^[83,99,100]IR (KBr disk)

analysis of polynorbornene (Figure S3, SI) showed no

absorbance in the 1600–1670 cm^ꢀ1range, indicating

that polymerization occurred via a vinyl addition path-

way.^[101]Notably, the IR spectrum of PNB obtained

using 4b showed the presence of weak bands at 1732

and 1717 cm^ꢀ1, indicative of C=O from the acac end

group in the polymer (Figure S3, SI). Ther-

mogravimetric analyses (Figures S4 and S5, SI) of the

polymers also yielded typical high decomposition tem-

peratures between 400^ꢂC and 420^ꢂC for the vinyl

addition PNB.

AUTHOR CONTRIBUTIONS

Dmitry Suslov: Conceptualization; investigation; super-

vision. Zorikto Abramov: Investigation. Ilya Babenko:

Investigation. Viktor Bezborodov: Investigation.

Tatyana Borodina: Investigation. Mikhail Bykov:

Investigation. Marina Pakhomova: Investigation.

Vladimir

Smirnov:

Investigation.

Anastasia

Ratovskii:

Suchkova:

Investigation.

Gennadii

Investigation. Igor Ushakov: Investigation. Alexey

Vilms: Investigation.

AUTHOR CONTRIBUTIONS

Conceptualization: D.S. Suslov (SDS); Investigation:

M.V.

Bykov

(BMV),

Z.D.

Abramov

(AZD),

SUSLOV ET AL.

25 of 27

[8] D. E. Janzen, D. G. VanDerveer, L. F. Mehne, D. A. da Silva

Filho, J.-L. Brédas, G. J. Grant, Dalton Trans. 2008, 2, 1872.

[9] T. P. Latendresse, S. J. Adams, G. J. Grant, J. P. Lee, A. G.

Oliver, Polyhedron 2016, 114, 80.

[10] D. E. Janzen, M. A. Bruening, A. A. Mamiya, L. E. Driscoll,

D. A. Da Silva Filho, Dalton Trans. 2019, 48, 11520.

M.V. Pakhomova, A.V. Suchkova (AVS), SDS,

I.A. Ushakov (UIA) (NMR), T.N. Borodina (BTN) (XRD),

V.I. Smirnov (SVI) (XRD), G.V. Ratovskii (FTIR),

A.I. Vilms (Ligands Syntheses), I.A. Babenko (Ligands

Syntheses), V.A. Bezborodov (Ligands Syntheses);

Writing - Original Draft: SDS; Writing - Review &

Editing: SDS, BMV, UIA, BTN, SVI, AZD, AVS, VAB;

Supervision: D.S. Suslov.

[11] S. Q. Bai, T. S. A. Hor, Chem. Commun. 2008, 3172.

ꢀ

[12] A. Tamayo, L. Escriche, J. Casabo, B. Covelo, C. Lodeiro,

Eur. J. Inorg. Chem. 2006, 2006, 2997.

[13] S. Kumar, G. K. Rao, A. Kumar, M. P. Singh, A. K. Singh,

Dalton Trans. 2013, 42, 16939.

[14] K. Nakajima, T. Kajino, M. Nonoyama, M. Kojima, Inorg.

Chim. Acta 2001, 312, 67.

[15] E. Stephen, A. J. Blake, E. Carter, D. Collison, E. S. Davies, R.

Edge, W. Lewis, D. M. Murphy, C. Wilson, R. O. Gould, A. J.

Holder, J. McMaster, M. Schröder, Inorg. Chem. 2012, 51,

1450.

DATA AVAILABILITY STATEMENT

The data that supports the findings of this study are

available in the supplementary material of this article

ORCID

Dmitry S. Suslov https://orcid.org/0000-0003-3835-0797

[16] D. E. Janzen, M. A. Bruening, C. A. Sutton, A. R. Sharma,

J. Organomet. Chem. 2015, 777, 31.

[17] G. J. Grant, D. A. Benefield, D. G. VanDerveer, Dalton Trans.

2009, 8605.

[18] G. J. Grant, D. A. Benefield, D. G. VanDerveer, J. Organomet.

Chem. 2010, 695, 634.

[19] S. Chatterjee, J. A. Krause, W. B. Connick, C. Genre, A.

Rodrigue-Witchel, C. Reber, Inorg. Chem. 2010, 49, 2808.

[20] T. W. Green, R. Lieberman, N. Mitchell, J. A. Krause Bauer,

W. B. Connick, Inorg. Chem. 2005, 44, 1955.

Zorikto D. Abramov https://orcid.org/0000-0002-1302-

7822

Ilya A. Babenko https://orcid.org/0000-0002-8754-1357

Viktor A. Bezborodov https://orcid.org/0000-0002-8363-

5698

Tatyana N. Borodina https://orcid.org/0000-0002-9034-

2930

Mikhail V. Bykov https://orcid.org/0000-0003-0899-

8760

[21] R. B. Bedford, M. Betham, C. P. Butts, S. J. Coles, M. B.

Hursthouse, P. Noelle Scully, J. H. R. Tucker, J. Wilkie, Y.

Willener, Chem. Commun. 2008, 2429.

[22] E. Stephen, A. J. Blake, E. S. Davies, J. McMaster, M.

Schröder, Chem. Commun. 2008, 5707.

Marina V. Pakhomova https://orcid.org/0000-0002-

7881-8078

Vladimir I. Smirnov https://orcid.org/0000-0002-2697-

3375

Anastasia V. Suchkova https://orcid.org/0000-0002-

2076-883X

[23] L. M. Mirica, J. R. Khusnutdinova, Coord. Chem. Rev. 2013,

257, 299.

Gennadii V. Ratovskii https://orcid.org/0000-0002-

4921-112X

[24] G. J. Grant, N. J. Spangler, W. N. Setzer, D. G. VanDerveer,

L. F. Mehne, Inorg. Chim. Acta 1996, 246, 31.

[25] J. P. Lee, C. L. Keller, A. A. Werlein, D. E. Janzen, D. G.

VanDerveer, G. J. Grant, Organometallics 2012, 31, 6505.

[26] C. Bariashir, C. Huang, G. A. Solan, W. H. Sun, Coord. Chem.

Rev. 2019, 385, 208.

[27] T. Agapie, Coord. Chem. Rev. 2011, 255, 861.

[28] K. A. Alferov, G. P. Belov, Y. Meng, Appl. Catal. A. Gen.

2017, 542, 71.

Igor A. Ushakov https://orcid.org/0000-0003-0176-1699

Alexey I. Vilms https://orcid.org/0000-0002-1698-1160

REFERENCES

[1] S. G. Murray, F. R. Hartley, Chem. Rev. 1981, 81, 365.

[2] W. K. Musker, Coord. Chem. Rev. 1992, 117, 133.

ꢀ

[3] A. Masdeu-Bulto, Coord. Chem. Rev. 2003, 242, 159.

[29] D. S. McGuinness, P. Wasserscheid, W. Keim, D. Morgan,

J. T. Dixon, A. Bollmann, H. Maumela, F. Hess, U. Englert,

J. Am. Chem. Soc. 2003, 125, 5272.

[30] N. Bahri-laleh, M. Nekoomanesh-haghighi, S. Sadjadi,

Polyolefins J. 2016, 3, 11.

[4] M. Arca, A. J. Blake, J. Casabò, F. Demartin, F. A.

Devillanova, A. Garau, F. Isaia, V. Lippolis, R. Kivekas, V.

Muns, M. Schröder, G. Verani, J. Chem. Soc. Dalton Trans.

2001, 1180.

[5] J. P. Tidey, A. E. O'Connor, A. Markevich, E. Bichoutskaia,

J. J. P. Cavan, G. A. Lawrance, H. L. S. Wong, J.

McMaster, M. Schröder, A. J. Blake, Cryst. Growth Des.

2015, 15, 115.

[31] C. Tan, C. Chen, Angew. Chem. Int. Ed. 2019, 58, 7192.

[32] Y. Na, D. Zhang, C. Chen, Polym. Chem. 2017, 8, 2405.

[33] S. Dai, S. Li, G. Xu, C. Chen, Macromolecules 2020, 53,

2539.

[6] M. Arca, A. J. Blake, V. Lippolis, D. R. Montesu, J.

McMaster, L. Tei, M. Schröder, Eur. J. Inorg. Chem. 2003,

2003, 1232.

[7] S. N. Dmitrieva, N. I. Sidorenko, N. A. Kurchavov, A. I.

Vedernikov, A. Y. Freidzon, L. G. Kuz'Mina, A. K. Buryak,

T. M. Buslaeva, A. A. Bagatur'Yants, Y. A. Strelenko, J. A. K.

Howard, S. P. Gromov, Inorg. Chem. 2011, 50, 7500.

[34] C. Zou, C. Chen, Angew. Chem. Int. Ed. 2020, 59, 395.

[35] A. Keyes, H. E. Basbug Alhan, E. Ordonez, U. Ha, D. B.

Beezer, H. Dau, Y. Liu, E. Tsogtgerel, G. R. Jones, E. Harth,

Angew. Chem. Int. Ed. 2019, 58, 12370.

[36] D. S. Suslov, M. V. Bykov, A. V. Kuzmin, P. A. Abramov,

O. V. Kravchenko, M. V. Pakhomova, A. V. Rokhin, I. A.

Ushakov, V. S. Tkach, Cat. Com. 2018, 106, 30.

26 of 27

SUSLOV ET AL.

[37] D. S. Suslov, M. V. Bykov, P. A. Abramov, M. V. Pakhomova,

I. A. Ushakov, V. K. Voronov, V. S. Tkach, Inorg. Chem.

Commun. 2016, 66, 1.

[38] D. S. Suslov, M. V. Pahomova, P. A. Abramov, M. V. Bykov,

V. S. Tkach, Cat. Com. 2015, 67, 11.

[39] D. S. Suslov, M. V. Bykov, P. A. Abramov, M. V. Pahomova,

I. A. Ushakov, V. K. Voronov, V. S. Tkach, RSC Adv. 2015, 5,

104467.

[65] W. von Doering, K. C. Schreiber, J. Am. Chem. Soc. 1955,

77, 514.

[66] P. Mamalis, H. N. Rydon, J. Chem. Soc. 1955, 1049.

[67] K. Mori, Y. Nakamura, J. Org. Chem. 1969, 34, 4170.

[68] K. Gloe, P. Mühl, J. Beger, R. Jacobi, A. Urban, Zeitschrift für

Chemie 1985, 25, 99.

[69] E. W. Abel, S. K. Bhargava, K. Kite, K. G. Orrell, V. Šik, B. L.

Williams, Polyhedron 1982, 1, 289.

[40] D. S. Suslov, M. V. Pakhomova, M. V. Bykov, I. A. Ushakov,

V. S. Tkach, Cat. Com. 2019, 119, 16.

[70] H. W. Peindy N'dongo, S. Clément, S. Richeter, F. Guyon, M.

Knorr, P. Le Gendre, J. O. Bauer, C. Strohmann,

J. Organomet. Chem. 2013, 724, 262.

[71] J.-P. Perchard, M.-T. Forel, M.-L. Josien, J. Chim. Phys 1964,

61, 645.

[41] D. S. Suslov, M. V. Bykov, M. V. Pakhomova, P. A. Abramov,

I. A. Ushakov, V. S. Tkach, Cat. Com. 2017, 94, 69.

[42] D. S. Suslov, M. V. Bykov, Z. D. Abramov, I. A. Ushakov,

T. N. Borodina, V. I. Smirnov, G. V. Ratovskii, V. S. Tkach,

J. Organomet. Chem. 2020, 923, 121413.

[72] D. R. Allan, A. J. Blake, D. Huang, T. J. Prior, M. Schröder,

Chem. Commun. 2006, 2, 4081.

[43] I. Yoshida, H. Kobayashi, K. Ueno, J. Inorg. Nucl. Chem.

1973, 35, 4061.

[73] J. Errington, W. S. McDonald, B. L. Shaw, J. Chem. Soc. Dal-

ton Trans. 1980, 2309.

[44] D. S. Suslov, M. V. Bykov, M. V. Belova, P. A. Abramov, V. S.

Tkach, J. Organomet. Chem. 2014, 752, 37.

[74] J. K. Park, Y. G. Cho, S. S. Lee, B. G. Kim, Bull. Korean Chem.

Soc. 2004, 25, 85.

[45] V. Bezborodov, I. Babenko, I. Rozentsveig, N. Korchevin, E.

Levanova, V. Smirnov, T. Borodina, V. Saraev, A. Vilms,

Polyhedron 2018, 151, 287.

[75] J. Senegas, G. Bernardinelli, D. Imbert, J. G. Bunzli, P.

Morgantini, J. Weber, C. Piguet, Inorg. Chem. 2003, 42,

4680.

[46] F. Neese, Wiley Interdiscip. Rev. Comput. Mol. Sci. 2012,

2, 73.

[47] A. D. Becke, Phys. Rev. A 1988, 38, 3098.

[48] J. P. Perdew, Phys. Rev. B 1986, 33, 8822.

[49] K. Eichkorn, O. Treutler, H. Öhm, M. Häser, R. Ahlrichs,

Chem. Phys. Lett. 1995, 242, 652.

[50] M. Bühl, H. Kabrede, J. Chem. Theory Comput. 2006, 2,

1282.

[51] M. Bühl, C. Reimann, D. A. Pantazis, T. Bredow, F. Neese,

J. Chem. Theory Comput. 2008, 4, 1449.

[52] C. J. Cramer, D. G. Truhlar, Phys. Chem. Chem. Phys. 2009,

11, 10757.

[53] M. Waller, H. Braun, N. Hojdis, M. Bühl, J. Chem. Theory

Comput. 2007, 3, 2234.

[54] M. J. Szabo, R. F. Jordan, A. Michalak, W. E. Piers, T. Weiss,

S.-Y. Yang, T. Ziegler, Organometallics 2004, 23, 5565.

[55] S. Tobisch, T. Ziegler, J. Am. Chem. Soc. 2004, 126, 9059.

[56] F. Weigend, Phys. Chem. Chem. Phys. 2006, 8, 1057.

[57] F. Weigend, R. Ahlrichs, Phys. Chem. Chem. Phys. 2005, 7,

3297.

[76] F. Blank, C. Janiak, Coord. Chem. Rev. 2009, 253, 827.

[77] M. V. Bermeshev, P. P. Chapala, Prog. Polym. Sci. 2018,

84, 1.

[78] V. R. Flid, M. L. Gringolts, R. S. Shamsiev, E. S. Finkelshtein,

Russ. Chem. Rev. 2018, 87, 1169.

[79] D. S. Suslov, M. V. Bykov, O. V. Kravchenko, Polym. Sci. Ser.

C 2019, 61, 145.

[80] G. Myagmarsuren, V. S. Tkach, D. S. Suslov, F. K. Shmidt,

Russ. J. Appl. Chem. 2007, 80, 252.

[81] G. Myagmarsuren, K. Lee, O. Jeong, S. Ihm, Cat. Com. 2003,

4, 615.

[82] P. Lassahn, V. Lozan, B. Wu, A. S. Weller, C. Janiak, Dalton

Trans. 2003, 4437.

[83] F. Blank, J. K. Vieth, J. Ruiz, V. Rodríguez, C. Janiak,

J. Organomet. Chem. 2011, 696, 473.

[84] C. Janiak, P.-G. Lassahn, Polym. Bull. 2002, 47, 539.

[85] M. Yamashita, I. Takamiya, K. Jin, K. Nozaki, Organometal-

lics 2006, 25, 4588.

[86] G. Myagmarsuren, K. S. Lee, O. Y. Jeong, S. K. Ihm, Polymer

(Guildf) 2005, 46, 3685.

[58] G. M. Sheldrick, Acta Crystallogr. Sect. A Found. Crystallogr.

2008, 64, 112.

[87] G. Myagmarsuren, K. S. Lee, O. Y. Jeong, S. K. Ihm, Polymer

(Guildf) 2004, 45, 3227.

[59] Bruker, SADABS, Bruker AXS Inc, Madison, Wis-consin,

USA 2001.

[88] V. S. Tkach, G. Myagmarsuren, D. S. Suslov, T. Darjaa, D.

Dorj, F. K. Shmidt, Cat. Com. 2008, 9, 1501.

[89] S. Okeya, H. Sazaki, M. Ogita, T. Takemoto, Y. Onuki, Y.

Nakamura, B. K. Mohapatra, S. Kawaguchi, Bull. Chem. Soc.

Jpn. 1981, 54, 1978.

[60] N. A. Korchevin, N. V. Russavskaya, O. V. Alekminskaya,

E. N. Deryagina, Russ. J. Gen. Chem. 2002, 72, 240.

[61] E. P. Levanova, A. I. Vilms, V. A. Bezborodov, I. A. Babenko,

N. G. Sosnovskaya, N. V. Istomina, A. I. Albanov, N. V.

Russavskaya, I. B. Rozentsveig, Russ. J. Gen. Chem. 2017,

87, 396.

[90] M.-T. Forel, M. Fouassier, M. Tranquille, Spectrochim. Acta

Part a Mol. Biomol. Spectrosc 1970, 26A, 1761.

ꢀ

[91] M. Gayoso, A. Suarez, J. M. Vila, E. Gayoso, Rev. Port. Quim.

[62] V. Y. Vshivtsev, E. P. Levanova, V. A. Grabel'nykh, L. V.

Klyba, E. R. Zhanchipova, E. N. Sukhomazova, A. A.

Tatarinova, A. I. Albanov, N. V. Russavskaya, N. A.

Korchevin, Russ. J. Org. Chem. 2008, 44, 43.

[63] C. R. Lucas, W. Liang, D. O. Miller, J. N. Bridson, Inorg.

Chem. 1997, 36, 4508.

1984, 26, 21.

[92] Z. Jiang, A. Sen, Organometallics 1993, 12, 1406.

[93] V. S. Tkach, D. S. Suslov, G. Myagmarsuren, G. V. Ratovskii,

A. V. Rohin, F. Tuczek, F. K. Shmidt, J. Organomet. Chem.

2008, 693, 2069.

[94] D. V. Sevenard, O. G. Khomutov, N. S. Boltachova, V. I.

Filyakova, V. Vogel, E. Lork, V. Y. Sosnovskikh, V. O.

[64] E. W. Abel, K. Kite, P. S. Perkins, Polyhedron 1986, 5, 1459.

SUSLOV ET AL.

27 of 27

Iaroshenko, G.-V. Röschenthaler, Zeitschrift für Naturforsch.

SUPPORTING INFORMATION

B 2009, 64, 541.

Additional supporting information may be found online

in the Supporting Information section at the end of this

article.

[95] J. P. Mathew, A. Reinmuth, J. Melia, N. Swords, W. Risse,

Macromolecules 1996, 29, 2755.

[96] R. Wang, X. Sui, W. Pang, C. Chen, ChemCatChem 2016,

8, 434.

[97] C. Chen, Nat. Rev. Chem. 2018, 2, 6.

[98] Y. Na, X. Wang, K. Lian, Y. Zhu, W. Li, Y. Luo, C. Chen,

ChemCatChem 2017, 9, 1062.

[99] J. Deng, H. Gao, F. Zhu, Q. Wu, Organometallics 2013, 32,

4507.

How to cite this article: D. S. Suslov, Z.

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I. Smirnov, A. V. Suchkova, G. V. Ratovskii, I.

A. Ushakov, A. I. Vilms, Appl Organomet Chem

2021, e6381. https://doi.org/10.1002/aoc.6381

[100] A. Sachse, S. Demeshko, S. Dechert, V. Daebel, A. Lange, F.

Meyer, Dalton Trans. 2010, 39, 3903.

[101] X. Mi, Z. Ma, N. Cui, L. Wang, Y. Ke, Y. Hu, J. Appl. Polym.

Sci. 2003, 88, 3273.

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Synthesis of mononuclear and dinuclear palladium (II) complexes containing oxadithioether ligands and their catalytic activities in norbornene polymerization

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