[Pd(acac)(L)2][BF4] (L?=?morpholine, diethylamine, dibutylamine, dioctylamine): Synthesis, structure and their catalytic activity

Article abstract of DOI:10.1016/j.molstruc.2016.12.025

Cationic acetylacetonate bis(secondary amine) palladium (II) complexes were synthesized by nitrile substitution of [Pd(acac)(MeCN)₂][BF₄] with L (L?=?morpholine, diethylamine, dibutylamine, dioctylamine) which yielded [Pd(acac)(L)₂][BF₄] as a mononuclear species with chelating acac ligand. An X-ray diffraction, NMR, IR and DFT study of [Pd(acac){morpholine}₂][BF₄] establishes the presence of hydrogen bonding between the morpholine ligand and [BF₄]^? anion. Crystallographic defects in the crystal and presence of pseudocrystalline structure in solution of [Pd(acac){morpholine}₂][BF₄] were assumed to explain IR spectra features. Preliminary investigations into the polymerization of norbornene, dimerization of styrene, and telomerization of 1,3-butadiene with diethylamine were performed.

Full text of DOI:10.1016/j.molstruc.2016.12.025

Accepted Manuscript
[Pd(acac)(L) ][BF ] (L = morpholine, diethylamine, dibutylamine, dioctylamine):
2
4
Synthesis, structure and their catalytic activity
D.S. Suslov, M.V. Bykov, G.V. Ratovskii, P.A. Abramov, M.V. Pahomova, I.A.
Ushakov, V.K. Voronov, V.S. Tkach
PII:
S0022-2860(16)31315-1
10.1016/j.molstruc.2016.12.025
MOLSTR 23223
DOI:
Reference:
To appear in: Journal of Molecular Structure
Received Date: 26 October 2016
Revised Date: 7 December 2016
Accepted Date: 7 December 2016
Please cite this article as: D.S. Suslov, M.V. Bykov, G.V. Ratovskii, P.A. Abramov, M.V. Pahomova, I.A.
Ushakov, V.K. Voronov, V.S. Tkach, [Pd(acac)(L) ][BF ] (L = morpholine, diethylamine, dibutylamine,
2
4
dioctylamine): Synthesis, structure and their catalytic activity, Journal of Molecular Structure (2017), doi:
10.1016/j.molstruc.2016.12.025.
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to
our customers we are providing this early version of the manuscript. The manuscript will undergo
copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please
note that during the production process errors may be discovered which could affect the content, and all
legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT
[Pd(acac)(L)2][BF4] (L = morpholine, diethylamine, dibutylamine,
dioctylamine): synthesis, structure and their catalytic activity
D.S. Suslova†, M.V. Bykova, G.V. Ratovskiia, P.A. Abramovb,c, M.V. Pahomovaa, I.A. Ushakovd,
V.K. Voronovd, V.S. Tkacha
aIrkutsk State University, ul. K.Marksa, 1, Irkutsk, Russia, 664003
bNikolaev Institute of Inorganic Chemistry SB RAS, pr-kt Akad. Lavrentieva, 3,
Novosibirsk, Russia, 630090
cNovosibirsk State University,ul. Pirogova, 2, Novosibirsk, Russia, 630090
dNational Research Irkutsk State Technical University, Lermontov St, 83, Irkutsk,
Russia, 664074
†Correspondence
should
be
addressed:
e-mail:
suslov@chem.isu.ru;
suslov.dmitry@gmail.com.
Abstract
Cationic acetylacetonate bis(secondary amine) palladium (II) complexes were
synthesized by nitrile substitution of [Pd(acac)(MeCN)2][BF4] with L (L = morpholine,
diethylamine, dibutylamine, dioctylamine) which yielded [Pd(acac)(L)2][BF4] as a
mononuclear species with chelating acac ligand. An X-ray diffraction, NMR, IR and DFT
study of [Pd(acac){morpholine}2][BF4] establishes the presence of hydrogen bonding
between the morpholine ligand and [BF4]− anion. Crystallographic defects in the crystal and
presence of pseudocrystalline structure in solution of [Pd(acac)(morph)2][BF4] were
assumed to explain IR spectra features. Preliminary investigations into the polymerization
of norbornene, dimerization of styrene, and telomerization of 1,3-butadiene with
diethylamine were performed.
Keywords
Palladium, acetylacetonate, secondary amine, norbornene, 1,3-butadiene, styrene
Introduction
The cationic palladium complexes are widely used as catalyst precursors in a variety
of olefin transformations. Transition-metal-catalyzed olefin oligomerization and
polymerization reactions constitute one of the most important industrial processes for
forming polyolefins and α-olefins [1–4]. In the past decades, the late transition-metal
palladium(II) and nickel(II) catalysts for olefin polymerization have attracted considerable
attention in both the academic and industrial fields due to their low electrophilicity and

ACCEPTED MANUSCRIPT
more heteroatom tolerance [5–8]. Oligomerization (and polymerization) catalysis typically
involves either a sensitive organometallic precursor or activators such as aluminum alkyls,
usually with exclusion of air and water, with MAO being the activator of choice here [5,6].
Exceptions are cationic palladium-(II) complexes such [Pd(η3-allyl)(L)2]Y (Y = BF4, PF6,
SbF6, BAF, etc) [9–16], [(L^L)PdMe(solv)]BAF (L^L=α-diimine, P^O, solv = MeCN, dmso)
[5,17–20], [(α-diimine)Pd((CH2)3C(O)OCH3)]BAF [5], [Pd(NCCH3)4](BF4)2 [11,21–23],
[Pd(PPh3)3(NCCH3)](BF4)2 [24,25], [(α-diimine)Pd(NCCH3)2][BF4]2 [26], [(α-diimine)Pd(μ-
OH)]2[BF4]2 [27], which require no cocatalyst for their activation toward olefins
oligomerization and polymerization. Aluminum alkyls free cationic Pd-catalyzed systems
with O⌢O-chelating ligands (O⌢O = β-diketonates or carboxylates) in combination with
Lewis acids such as BF3·OEt2, In(OTf)3 or Cu(OTf)2 have shown promising results for
oligomerization of ethylene [28], selective dimerization of styrene [29–33], polymerization
of norbornene and its derivates [34–36].
Recently we reported synthesis of novel acetylacetonate cationic palladium
complexes with mono-/bidentate phosphines, α-diimine and aniline ligands as well as the
results of their usage as efficient precursors for the selective dimerization of styrene
[33,37], telomerization of butadiene with diethylamine [38], polymerization of norbornene
[37,39,40]. As part of our ongoing research in the field of late transition metals oligo-
/polymerization catalysis, we describe here the synthesis of cationic palladium
acetylacetonate complexes containing secondary amine ligands. Amines are ubiquitous
ligands in transition-metal chemistry. They bind to metals in enzymes, classical
coordination complexes, and organometallic compounds. In spite of their importance they
were not often used in olefins oligo- and polymerization reaction as catalysts precursors.
Compared to the large number of known bis(amine)palladium complexes, the palladium
complexes that contain secondary amine ligands in cis-position are rare [41,42]. In order to
examine the influence of the secondary amine structure on the catalytic properties, the
addition polymerization of norbornene, dimerization of styrene, and telomerization of 1,3-
butadiene with diethylamine with these complexes were also investigated.
1. Experimental Section
1.1.
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 was
purified before feeding to the reactor by passing through columns packed with oxygen

ACCEPTED MANUSCRIPT
scavenger (Fisher REDOX) and molecular sieve 5A (Aldrich), respectively. Diethyl ether,
benzene and hexane were distilled from sodium−benzophenone. CH2Cl2, CH3CN,
diethylamine, morpholine, dibutylamine, and dioctylamine were distilled from CaH2.
Solvents were stored over molecular sieves. All glassware was dried for at least 3 h in a
150°C oven and cooled under an argon atmosphere. Styrene (99%, Aldrich) was purified by
distillation under reduced pressure over CaH2. Norbornene (Acros, 99%) were distilled
from sodium-benzophenone and used as a solution (80 wt.%) in CH2Cl2. 1,3-butadiene
(Aldrich, 98%) was used as received. BF3⋅OEt2 (Acros, 99%) was distilled over CaH2 prior
to use. Pd(acac)2 was synthesized according to a literature procedure [43] and
recrystallized from acetone. [Pd(acac)(MeCN)2][BF4] was prepared according to literature
procedure [37]. All other reagents were obtained commercially and used as received. All
NMR spectra were recorded at room temperature on Varian VXR-500S, Brucker DPX-250,
or Brucker DPX-400 spectrometers. IR spectra were recorded on a Simex Infralum FT 801
spectrometer. TG/DSC measurements were performed with a Netzsch STA 449-F3
instrument. The products of the catalytic runs were analyzed by GC–MS (Shimadzu QP2010
Ultra , GSBP-5MS capillary column) and GC (Chromatec, Crystall 5000.2, SGE BPX-5
capillary column).
General procedure for catalytic telomerizations of 1,3-butadiene. Palladium
complex (0.013 mmol) and phosphine ligand (0.013 mmol) were added in a dried and
sealed vessel under argon. The stainless steel autoclave was cooled with liquid nitrogen
and 4.2 g (78 mmol) of 1,3-butadiene was condensed (volume and mass control).
Afterwards cold (-15°C) diethylamine (5.4 mL, 42.5 mmol) was added via syringe into the
cooled (-10°C) autoclave and the vessel was heated to the desired reaction temperature.
After 3 h the autoclave was cooled to room temperature and 1 mL of benzene as internal
standard was added. In general, the yield of telomers was determined by GC. The main
product was isolated from the reaction mixture via distillation and analyzed by GC-MS and
1H,13C NMR.
General procedure for catalytic dimerization of styrene.
A mixture of the styrene (132 mmol), 1.3 mL of CH2Cl2, 2 mL C6H6 (internal
standard), and palladium complex (4.4 μmol) were placed in a 25 mL glass flask equipped
with a magnetic stirring bar. Dimerizations were initiated by the injection of boron
compound.The reaction was carried out at 50 °C for 5 h with stirring. The conversion and
selectivity were determined by GC. The main product was isolated from the reaction
mixture via distillation and analyzed by GC-MS and 1H,13C NMR.

ACCEPTED MANUSCRIPT
General procedure for catalytic polymerization of norbornene.
Polymerizations were carried out in a 10-mL glass reactor equipped with a magnetic
stirrer. The reactor was filled with norbornene as a solution in CH2Cl2, the solution was
kept at desired temperature for 15 min and then the palladium complex was added.
Polymerizations were initiated by the injection of boron compound. After stirring for a time
needed, the polymers formed were precipitated in ethanol. The precipitated polymers were
washed three times with ethanol, and dried in vacuum at 80 °C for 6 h.
1.2.
Syntheses of complexes
Preparation of [Pd(acac)(NHEt2)2][BF4] (1)
[Pd(acac)(MeCN)2]BF4 (0.5618 g, 1.5 mmol) was added slowly to solution of
diethylamine (0.33 mL) in CH2Cl2 (10 mL) and stirred at room temperature for 1 h. The
reaction mixture was cooled to −18 °C and stored overnight. The solvent was removed in
vacuo, and the yellow residue was washed twice with Et2O and dried under vacuum. Yield:
0.5244 g (80%). Anal. Calcd for C13H29BF4N2O2Pd: C, 35.60; H, 6.66; F, 17.33. Found: C,
1
35.61; H, 6.42; F, 17.56. H NMR (400.1 MHz, CDCl3): δ 1.56 (dd, J = 7.2 Hz, 12H, CH3,
NHEt2), 2.00 (s, 6Н, CH3 , acac), 2.55 (dq, J = 7.1 Hz, 14 Hz, 4H, CH2, NHEt2), 2.87 (dq, J = 7,2
Hz, 14.5 Hz, 4H, CH2 , NHEt2, 4.18 (br., 2H, NH, NHEt2), 5.40 (s, 1H, CH, acac). 13C{1H} NMR
(100.7 MHz, CDCl3): δ 14.27 (CH3, NHEt2), 26.21 (CH3 , acac), 47.23 (CH2, NHEt2), 101.28
(CH, acac), 186.70 (C=O, acac). 19F NMR (376.3 MHz, CDCl3): δ −150.12 (s, 1F), −150.17 (d,
10
J=1.1 Hz, 4F) (BF4, the integral ratio of the two signals is 1:4 equal to the B/11B isotopic
10
11
ratio, natural isotopic abundance: B/11B=19.4%/80.6%). B NMR (128.3 MHz, CDCl3): δ
−1.17 (BF4). 15N NMR (40.5 MHz, CDCl3): δ –364.65 (J = 71.7 Hz).
Preparation of [Pd(acac)(morph)2][BF4] (2)
[Pd(acac)(MeCN)2]BF4 (0.5618 g, 1.5 mmol) was added slowly to solution of
morpholine (0.26 mL) in CH2Cl2 (10 mL) and stirred at room temperature for 1 h. The
reaction mixture was cooled to −18 °C and stored overnight. The solvent was removed in
vacuo, and the yellow residue was washed twice with Et2O and dried under vacuum. Yield:
0.6300 g (90%). Anal. Calcd for C13H25BF4N2O4Pd: C, 33.47; H, 5.40; F, 16.29. Found: : C,
33.79; H, 5.41; F, 17.43. 1H NMR (400.1 MHz, CDCl3): δ 2.06 (s, 6Н, CH3, acac), 3.01 (br.d., J =
12.7 Hz, 4H, He , α-CH2 in morph), 3.22 (qd, J =12.2, 3.4 Hz, 4H, Hа, α-CH2 in morph), 3.73
(dd, J = 12.4, 3.1 Hz, 4H, He, β-CH2 in morph), 3.90 (td (br.), J = 12.0, 1.3 Hz, 4H, Ha, β-CH2 in
morph), 4.65 (br.(dd), J = 10.5 Hz, 2H, Ha, NH in morph), 5.48 (s, 1H, CH, acac). 13C{1H} NMR
(100.7 MHz, CDCl3): δ 26.28 (CH3, acac), 50.01 (α-CH2 in morph), 66.64 (β-CH2 in morph),
101.85 (CH, acac), 186.98 (C=O, acac). 19F NMR (376.3 MHz, CDCl3): δ −148.26 (br., J = 2 Hz,

ACCEPTED MANUSCRIPT
1F), −148.31 (d, J = 2.5 Hz, 4F) (BF4, the integral ratio of the two signals is 1:4 equal to the
10B/11B isotopic ratio, natural isotopic abundance: 10B/11B=19.4%/80.6%). 11B NMR (128.3
15
MHz, CDCl3): δ −1.01 (br.qnt, J = 2 Hz, BF4). N NMR (40.5 MHz, CDCl3): δ –385.3 (J = 72.1
Hz).
Preparation of [Pd(acac){NH(n-Bu)2}2][BF4] (3)
[Pd(acac)(MeCN)2]BF4 (0.5618 g, 1.5 mmol) was added slowly to solution of
dibutylamine (0.53 mL) in CH2Cl2 (10 mL) and stirred at room temperature for 1 h. The
reaction mixture was cooled to −18 °C and stored overnight. The solvent was removed in
vacuo, and the yellow residue was washed twice with Et2O and dried under vacuum. Yield:
0.5700 g (69%). Anal. Calcd for C21H45BF4N2O2Pd: C, 45.79; H, 8.23; F, 13.80. Found: CC,
1
45.96; H, 7.91; F, 14.36. H NMR (250 MHz, CDCl3): δ 0.96 (dd, J = 7.27 Hz, 12H, CH3,
NHBu2), 1.37 (m, 8H, γ-CH2, NHBu2), 1.85 (m, 4H, β-CH2, NHBu2), 1.99 (s, 6H, CH3, acac),
2.22 (m, 4Н, β-CH2, NHBu2), 2.40 (m, 4H, α-CH2, NHBu2), 2.76 (m, 4H, α-CH2, NHBu2), 4.22
13
(br., 2H, NH, NHBu2), 5.42 (s, 1H, CH, acac). C{1H} NMR (50 MHz, CDCl3): δ 13.90 (CH3,
NHBu2), 20.54 (γ-CH2, NHBu2), 26.20 (CH3, acac), 31.22 (β-CH2, NHBu2), 52.98 (α-CH2,
NHBu2), 101.36 (CH, acac), 186.63 (C=O, acac).
Preparation of [Pd(acac){NH(n-Oct)2}2][BF4] (4)
[Pd(acac)(MeCN)2]BF4 (0.5618 g, 1.5 mmol) was added slowly to solution of
dioctylamine (0.90 mL) in CH2Cl2 (10 mL) and stirred at room temperature for 1 h. The
reaction mixture was cooled to −18 °C and stored overnight. The solvent was removed in
vacuo, and the yellow residue was washed twice with Et2O and dried under vacuum. Yield:
0.9300 g (80%). Anal. Calcd for C37H77BF4N2O2Pd: C, 57.32; H, 10.01; F, 9.80. Found: C,
1
57.49; H, 10.21; F, 10.34. H NMR (400.1 MHz, CDCl3): δ 0.87 (dd, J = 6.5 Yz, 12H, CH3,
NHOct2), 1.29 (br., 40H, γ–η-CH2, NHOct2), 1.86 (m, 4H, β-CH2, NHOct2), 1.99 (s, 6H, CH3,
acac), 2.24 (m, 4Н, β-CH2, NHOct2), 2.38 (m, 4H, α-CH2, NHOct2), 2.74 (m, 4H, α-CH2,
NHOct2), 4.22 (br, 2H, NH, NHOct2), 5.42 (s, 1H, CH, acac). 13C{1H} NMR (100.7 MHz, CDCl3):
δ 14.17 (CH3, NHOct2), 22.72 (η-CH2, NHOct2), 26.15 (CH3, acac), 27.32 (ζ-CH2, NHOct2),
29.19 (ε-CH2, NHOct2), 29.29 (δ-CH2, NHOct2), 29.37 (γ-CH2, NHOct2), 31.89 (β-CH2,
19
NHOct2), 53.24 (α-CH2, NHOct2), 101.25 (CH, acac), 186.56 (C=O, acac). F NMR (376.3
MHz, CDCl3): δ −150.48 (br., 1F), −150.54 (s, 4F) (BF4, the integral ratio of the two signals is
1:4 equal to the 10B/11B isotopic ratio, natural isotopic abundance: 10B/11B=19.4%/80.6%).
11B NMR (128.3 MHz, CDCl3): δ −1.19 (br.qnt, J = 1.56 Hz, BF4). 15N NMR (40.5 MHz, CDCl3):
δ –373.4 (J = 68.3 Hz).
1.3.
Calculations

ACCEPTED MANUSCRIPT
All density functional theory calculations were performed with the ORCA
program.[44] All geometry optimizations were run with tight convergence criteria, using
the BP86 functional,[45,46] making use of the resolution of the identity technique.[47] The
applicability of gradient-corrected functionals as BP86 for the structural prediction of
transition metal compounds and reliable determination of the kinetic balance are well
documented [48–53]. The basis sets that were used were the Weigend−Ahlrichs basis sets
[54,55]. Triple-ξ-quality basis sets with one set of polarization functions (def2-TZVP) were
used for the palladium. The remaining atoms were described by slightly smaller def2-SVP
basis sets. A scalar relativistic correction was applied using the zeroth-order regular
approximation (ZORA) method [56–58]. Chemical shifts calculations were performed using
IGLO-III (C, H, N, O) and def2-TZVPP basis sets.
1.4.
X-ray Diffraction Studies
The diffraction data was collected on a Bruker X8Apex-II CCD diffractometer with
MoKα radiation (λ = 0.71073 Å) by doing ω and φ scans of narrow (0.5°) frames at 296 K.
The structure of [Pd(acac)(morph)2]BF4 was solved by direct methods and refined by full-
matrix least-squares treatment against |F|2 in anisotropic approximation with SHELX
2014/7 [59] in ShelXle program [60]. Absorption corrections were applied empirically
with SADABS [61]. Crystallographic data and refinement details are given in Table 1, bond
distances are summarized in Table S1. Further details may be obtained from the Cambridge
Crystallographic Data Center on quoting the depository number CCDC 1510187. Copies of
this information may be obtained free of charge from http://www.ccdc.cam.ac.uk.
Table 1
Experimental details for 2
Crystal data
Chemical formula
C13H25BF4N2O4Pd
466.56
Mr
Crystal system,
space group
Triclinic, P¯ 1
Temperature (K)
a, b, c (Å)
α, β, γ (°)
V (Å3)
296
8.6812 (3), 9.8778 (3), 12.0872 (4)
68.380 (1), 80.563 (2), 80.062 (2)
943.39 (5)
2
Z
Radiation type
Mo Kα
1.04
µ (mm-1)

ACCEPTED MANUSCRIPT
Crystal size (mm)
0.20 × 0.20 × 0.15
Data collection
Diffractometer
Bruker X8Apex
Absorption
correction
Multi-scan
SADABS (Bruker-AXS, 2004)
Tmin, Tmax
0.819, 0.860
No. of measured,
independent and
observed [I > 2σ(I)]
reflections
9237, 2883, 2686
Rint
0.033
23.9
θmax (°)
(sin θ/λ)max (Å-1)
0.570
Range of h, k, l
h = -9→9, k = -11→11, l = -13→13
Refinement
R[F2 > 2σ(F2)],
0.034, 0.099, 1.19
wR(F2), S
No. of reflections
No. of parameters
No. of restraints
H-atom treatment
2883
268
12
H atoms treated by a mixture of independent and constrained
refinement
2
w = 1/[σ2(Fo ) + (0.0245P)2 + 2.8477P]
Weighting scheme
where P = (Fo + 2Fc2)/3
2
∆〉max, ∆〉min (e Å-3)
0.71, -0.63
Computer programs: APEX2 (Bruker-AXS, 2004), SAINT (Bruker-AXS, 2004), SHELXS2014
(Sheldrick, 2014), SHELXL2014 (Sheldrick, 2014), ShelXle (Hübschle, 2011), CIFTAB-2014 (Sheldrick,
2014).
2. Results and discussion
2.1.
Synthesis and structure
[Pd(acac)(L)2][BF4] complexes 1-4 were prepared by following a similar procedure
to that for the synthesis of [Pd(acac)(NH2Ar)2][BF4] complexes [40], combining the
corresponding [Pd(acac)(MeCN)2][BF4] with an slight excess of secondary amine ligand in
CH2Cl2 at room temperature. After 2 h, removal of the solvent afforded the desired
complexes as yellow solids, which were then washed with cold Et2O. The complexes were
characterized by NMR and EA.

ACCEPTED MANUSCRIPT
Scheme 1
The solid-state structure of 2 was determined by X-ray diffraction. Crystals of 2
were grown from CH2Cl2 solution by overlaying with Et2O. An ORTEP plot of the
asymmetric unit cell is reported in Figure 1. The crystallographic data, and structure
refinement summary data for 2 are listed in Table 1 (see Experimental Section). The
coordination around palladium center is square-planar with two O atoms (d(Pd–
O)av. = 1.995[4] Å) and two N atoms (d(Pd–N)av. = 2.049[5] Å) of the organic ligands
coordinated in a cis-geometry. The N–Pd–N bond angle (90.3°) show no angle deformation
due to steric hindrance, and the O-Pd-O angle is 94.0°. The two coordination planes are
almost exactly parallel, the dihedral angle being 1.2° only. Slightly disordered [BF4]− anions
are in the second coordination sphere of Pd (d(Pd…B) = 5.329 Å) between two morpholine
ligands assuming the presence of hydrogen bonding between the NH group of the ligand
and one of the fluorides attached to the [BF4]− anion. For comparison, in
[Pd(acac)(dppp)][BF4] the distance between Pd and B atoms is 9,319 Å [38], and anion is
situated near phenyl ring of the diphosphine ligand.

ACCEPTED MANUSCRIPT
Fig. 1. Crystal structure of 2 with thermal ellipsoids drawn at the 50% probability level.
Hydrogen atoms are omitted for clarity.
Fig. 2. Three-dimensional representations of the calculated structures of molecular models
of 1 (a) and 2 (b).
To gain more insight into the structure of the cationic species, we performed DFT
calculations for the 1 and 2. Within the limits of the basis set employed, the optimized
geometry of 2 in gas phase was good representation of the structure obtained from the
crystallographic studies (Figure 2). Calculated molecular models of 1 and 2 consistently
showed the [BF4]− anion in a F3BF…H–N–Pd orientation. For 2 d(H1-F1) = 1,72 Å, d(H2-F1)
= 1,82 Å, B1–F1…H1 = 99.3°, B1–F1…H2 = 93.4°, N1–H1…F1 = 157.3°, N2–H2…F1 = 151.3°
are characteristic for hydrogen bonding and close to that encountered in the crystal
structure of cationic acetylacetonate bis-aniline analogue [40]. In the model of complex 1

ACCEPTED MANUSCRIPT
two fluorine atoms interacts with NH hydrogen and d(H1-F1) = 1,73 Å и d(H2-F2) = 1,73 Å,
B1–F1…H1 = 101.5°, B1–F2…H2 = 101.1°, N1–H1…F1 = 169.0°, N2–H2…F2 = 169.3°.
Consequently, hydrogen atoms in 1 are out of NPdN plane by 19 and 16 degrees. The
cation-anion interactions in 2 were assessed by stepwise assembly of the complex starting
from the [Pd(acac)(morph)2]+ cation. The electronic energy difference between the product
and the components from which the product was composed were calculated. Upon
introduction of the charge-compensating anion a large drop in energy (∆Ee of −110
kcal/mol) is gained with the formation of [Pd(acac)(morph)2][BF4] from
[[Pd(acac)(morph)2]+ and [BF4]−. Within the accuracy of the computational methods,
further calculations indicated that the effect of hydrogen bonding on the ∆Ee of ion-pairing
is marginal and the interaction with the anion must be electrostatic in nature. When
solvent effects were included with the COSMO model with CHCl3 as solvent, the ∆Ee of ion-
pairing was only −46 kcal/mol. The morpholine-anion interaction showed ∆Ee of −21.7 and
−15.0 kcal/mol in gas phase and CHCl3 respectively. Calculations performed on H…F
bonding between BF3 and morpholine indicate that the energy associated with the
formation of this bond is only –3 kcal/mol, which is characteristic for hydrogen-fluorine
bonds [62].
1
Comparison of the H NMR chemical shifts of the NH group from diethylamine
ligand in known palladium complexes showed strong dependence on the anion nature
(Table 2, from strongly coordinating to weakly coordinating anions). From the NMR
spectra of 1, the hydrogen bonding-induced shifts of the signals for the NH-protons of
diethylamine (Table 2) and for fluorine atoms in [BF4]− (Table 3), are also indicative of a
slight H…F interaction.
Table 2
Comparison of the 1H NMR chemical shifts of the NH group in diethylamine ligand
Complex
Chemical shift, ppm
Reference
[41]
[Pd(acac)(NHEt2)2](acac)
[Pd(acac)(NHEt2)2]BF4
[Pd(dmpe)(Me)(NHEt2)]BF4
[Pd(dmpe)(Me)(NHEt2)]BPh4
7.1
4.18
3.64
2.66
—
[63]
[63]

ACCEPTED MANUSCRIPT
Table 3
Comparison of the 19F NMR chemical shifts of the anion [BF4]−
Комплекс
Chemical shift, ppm
−153.6
Reference
[64]
[Pd(acac)(PPh3)2][BF4]
[Pd(acac)(MeCN)2][BF4]
[Pd(acac)(NHEt2)2][BF4]
[Pd(acac)(morph)2][BF4]
[Pd(acac){NH(n-Oct)2}2][BF4]
−152.1
[37]
−150.2
−148.3
−150.5
Fig. 3. Coordination of morpholine with palladium in 2.
For non-coordinated morpholine (OC4H8NH), eight protons attached to carbon give
two resonances at 2.9 ppm and 3.6 ppm [65], while spectra of 2 give four resonances as
illustrated in Figure 4. There are four multiples characterized for eight coordinated
morpholine protons attached to carbon (Figure 3). This is expected since upon
coordination to palladium, one chair conformation of morpholine is fixed. Proton Hꢀꢁ
interacts with germinal proton Hꢀꢂ (2Jae = 12,7 Hz) and with 3 vicinal protons, Hꢃꢂ , Hꢄꢂ , Hꢃꢁ
(with smaller coupling constants), therefore its resonance appears as broadened doublets
at 3.01 ppm (Fig. 4). Because proton Hꢀꢂ interacts with Hꢀꢁ , Hꢃꢂ , Hꢄꢂ and Hꢃꢁ its resonance
appears as a quartet of doublets centered at 3.22 ppm with 2Jae, 3Jaa, 3Jaa(N) ≈ 12.2 Hz and 3Jae
= 3.4 Hz. Proton Hꢃꢁ interacts with germinal proton Hꢃꢂ (2Jae = 12.4 Hz) and with 2 vicinal
ꢂ
ꢁ
3
protons Hꢀ and Hꢀ (with Jae = 3,1 Hz) giving a doublet of doublets or broadened doublets
at 3.73 ppm. Proton Hꢃꢂ is coupled to Hꢃꢁ, Hꢀꢂ, Hꢄꢂ and Hꢃꢁ giving a triplet of doublets
centered at 3.90 ppm with 3Jaa = 12,0 Hz, 2Jae ≈ 1,3 Hz. Comparing the 1H NMR spectrum of 2
with the reported spectra of neutral platinum morpholine complexes [65] one can see
some features. Chemical shifts of Hꢃ (3.73, 3.90 ppm) are more downfield than those of Hꢀ
(3.01, 3.22 ppm), while for the neutral platinum morpholine complexes the shifts are
reversed. These feature may be caused by the small interaction of beta protons with the
[BF4]− anion in second coordination sphere of Pd(II). The same trend is observed for 1.

ACCEPTED MANUSCRIPT
Chemical shifts of beta protons in diethylamine ligand (1.56 ppm) is slightly downfield than
those in non-hydrogen bonded [Pd(dmpe)(Me)(NHEt2)]BPh4 [63] (1.27 ppm) and in
calculated cation of 1 ([1.28]av. ppm, Table S2). 1H and 13C NMR chemical shifts for 1 and 2
have been calculated using the BP86 and B3LYP functionals with IGLO-III/def2-TZVPPPd
basis-set (Tables S2 and S3). Calculated chemical shifts were in good agreement with
experimental data for both used functionals. Signals from NH-group of amines are shifted
to low field due to the presence of hydrogen N–H…F bonds. For cation of complex 1 BP86
and B3LYP calculations showed δ(N-H) = 2.9 and 2.4 ppm respectively, which are similar to
chemical shift reported for [Pd(dmpe)(Me)(NHEt2)]BPh4 complex with non-coordinating
anion. As expected, upon introduction of the [BF4]− anion a major difference between
resonance signals of NH protons of the molecular model of complex 1 (δ(NH) = 6.4 ppm)
and its cation could be discerned.
Fig. 4. Fragment of 1H NMR spectrum of 2
The IR spectra of complex 2 exhibit bands at 3260 (ν1) cm–1 and 3340 (ν2) cm–1 with
peak intensity ratio of A1/A2 ≈ 15. These bands are referred to the NH stretching vibrations
of the ligand. Similar bands were observed in the spectrum of [(dmpe)Pd(Me)(NHEt2)]BF4
[63] (3264 cm–1 и 3384 cm–1), and for [trans-(morph)2Pd(OAc)2] (3304 and 3173 cm–1)

ACCEPTED MANUSCRIPT
[66]. It is worth noting that the structure [66] of trans-(morph)2Pd(OAc)2] contains one
crystallographically independent water molecule, which functions as a donor of two
hydrogen bonds with the carboxyl oxygen atoms not coordinated to the metal and the
acceptor of a hydrogen bond with the morpholine amino group. DFT calculations
(BP86/def2-SVPC,H,N/def2-TZVPPd) of vibrational spectra were used to elucidate the nature
of these bands. The comparison of the experimental and calculated wavenumbers of the
most intense vibrations and their assignment of complexes 1 and 2 are given in Tables S4-
S7, respectively. It is seen from Tables S4-S7 that the experimentally measured vibrational
wavenumbers of the species studied coincide well with the DFT theoretical predictions.
Calculated NH bands wavenumbers (average) are 3253 cm–1 (ν1) for 2 and 3357 cm–1 (ν2)
for its cation. Therefore, ν1 band refer to N–H…F bond vibrations which is offset by
interaction with [BF4]−. Subsequently, vibrational spectra of 2 were calculated with
constrained Pd and B coordinates. The l(B-Pd) was varied from 4.5 Å to 6.5 Å, Table 4.
During geometry optimization with l(B-Pd) = 6.0 Å and 6.5 Å one morpholine ligand is
rotated (∆Ee ≈ −10 kcal/mol). In this case, NH bond is out of the N-Pd-N angle plane by
41.6° (l(B-Pd) = 6.0 Å) or 68.8° (l(B-Pd) = 6.5 Å). Furthermore, the experimental
wavenumbers ν1(N–H) and ν2(N–H) are close to the calculated values with increasing B–Pd
distance (Table S8). The results of the calculations can be summarized by assuming
crystallographic defects in the crystal of 2. In the obtained crystal of the complex
[Pd(acac)(morph)2][BF4] in addition to the main structure, there are crystallographic
defects, in which the anion [BF4]− is at greater distances from the cation than in primary
structure (l(B-Pd) = 5,329 Å ). This is also confirmed by the observation of only one band
3260 (ν1) cm–1 in the IR spectrum of 2 in CH2Cl2. In addition, according to XRD two sets of
coordinates were obtained for fluorine atoms in [BF4]− anion . In our opinion, this indicates
the existence of two types [BF4]− anions. Analysis of bond lengths and angles (Table S9)
showed that the geometry of one of them were close to the tetrahedral.

ACCEPTED MANUSCRIPT
Fig. 5. IR spectra of 0.05M [Pd(acac)(morph)2]BF4 in the range of 1000-1200 cm–1 (KBr,
0.07 mm)
The IR spectrum of the crystal of complex 2 in the 1150–1000 cm–1 range exhibited
three bands from the antisymmetric stretching vibration of the tetrahedral anions. In an
ideal tetrahedral anion these vibrations are triply degenerate and the IR spectrum should
exhibit one band. In the crystal under the influence of the surrounding cations the anion
tetrahedral symmetry is distorted. Accordingly, in the spectrum of 2 we observed three
bands at 1118, 1083, and 1032 cm–1. Moreover, distortion of idealized tetrahedral
geometry of the anion [BF4]− leads to appearance in the spectrum of the symmetric
stretching vibration at 785 cm–1, forbidden in the infrared absorption spectrum. In the IR
spectra of solution of 2 (MeCN, CH2Cl2) these three bands (1120, 1087, and 1036 cm–1 in
MeCN; 1121, 1082, and 1041 cm–1 in CH2Cl2) were also registered. As can be seen from the
IR spectra for the solution and the crystal of 2 (Figure 5) full bands width (L) at half
maximum(A/2) are similar (Lcrystal = 123 cm–1 and Lsolution = 102 cm–1). Therefore, the
pseudocrystalline structures are present in the solution of 2, presumably consisting of a
several pairs of cations and anions. The opposite is observed in the IR spectrum of model
compound (NBu4)BF4 in CH2Cl2: only one band appeared at 1060 cm–1. The FT-IR spectrum
of (NBu4)BF4, recorded as Nujol mull, displays three bands (1099, 1050, and 1034 cm–1).
Full bands width (L) at half maximum(A/2) for solution and crystal of (NBu4)BF4 are rather
different (Lcrystal = 104 cm–1 and Lsolution = 55 cm–1). This indicates that cation-anion
interaction is disturbed whereby this vibration remains degenerate (Figure S1).
2.2.
Catalysis

ACCEPTED MANUSCRIPT
Telomerization of 1,3-butadiene with diethylamine. Telomerization, linear
dimerization of 1,3-dienes with simultaneous addition of a nucleophile in a catalytic
reaction, is a very efficient “green” organic transformation. Easily available starting
materials are converted in the presence of a catalyst in a 100% atom efficient manner to
give functionalized octa-2,7-dienes
The resulting products have been used as
intermediates in the total synthesis of several natural products, as well as precursors for
plasticizer alcohols, industrial monomers, solvents, corrosion inhibitors, and non-volatile
herbicides [67–69]. A series of palladium complexes with phosphines, diphospines and
NHC (NHC = N-heterocyclic carbene) ligands were reported for the telomerization of 1,3-
butadiene (BD) with amines, water and alcohols [38,67,68,70–78]. In exploratory
experiments using individual complexes 1-4 as catalysts we discovered that addition of
tertiary phosphine is required to obtain active catalyst (Table 6), opposite to the results
obtained previously for [Pd(acac)(NHEt2)2][BF4] [42]. Even at very low catalyst
concentration conversions up to 89.1% and excellent selectivity (99.9%) were observed
with complex 3 in combination with PiPr3. To our delight whatever the ligand present on
the palladium, only the linear telomerization product is formed. The ligand structure is
known to influence the product ratio in the telomerization reaction, but factors explaining
the changes in chemo- and regioselectivity remained unraveled. For complex 3 with
P(OEt)3 ligand reduced yield was observed (Table 6).
Table 6
Telomerization of 1,3-butadiene with diethylamine
TOF[d],
TON[d],
Entry Catalyst[a] Yield[b], % Selectivity[c], %
molBD/(molPd·h) molBD/molPd
1
2
3
4
5
7
8
1-4
0.3–0.9
85.7
99.9
99.9
99.9
99.9
99.9
99.9
99.9
∼5–20
1710
1430
1680
1780
1080
1690
∼20–60
5140
4290
5050
5350
3250
5060
3+PPh3
3+2PPh3
3+PnBu3
3+PiPr3
71.5
84.2
89.1
3+P(OEt)3 54.2
3+Pptol3
84.3

ACCEPTED MANUSCRIPT
[a] Reaction conditions: BD:Pd = 6000, Et2NH:Pd = 3270, 1.3·10-5 mol Pd (0.016 mol% with
respect to 1,3-butadiene), 70°C, 3 h; [b] Yield of octa-2,7-dienyldiethylamine. [c]Selectivity
toward octa-2,7-dienyldiethylamine. [d]Catalyst turnover frequency(number) with respect
to BD
Styrene dimerization. Diverse Ni-, Co-, and Pd-catalyzed co- and hetero-
dimerizations of ethylene and styrene have been developed. These new catalytic systems
have been successfully applied to selective C–C bond formation [12,64,79–87].
Furthermore, enantioselective syntheses of commercial non-steroidal anti-inflammatory
drugs such as ibuprofen, and the total syntheses of natural products with intricate methyl-
bearing stereogenic centers have been reported using these catalytic systems. This reaction
could be a test reaction to develop various co- and heterodimerization reactions [12]. In
contrast to reactions with BD, complexes 1–4 activated by treatment with BF3·OEt2 showed
styrene oligomerization. Styrene was converted with 1–4/nBF3·OEt2 highly chemo- and
stereospecifically to the head-to-tail dimer (E)-1,3-diphenyl-1-butene as the exclusive
dimerization product (Table 7). To investigate the effect of the amount of co-catalyst, a set
of runs was carried out with the B/Pd ratios from 5 to 15 at 50°C. As one may see in Table 7,
the conversion to dimers (selectivity) showed dramatic decrease due to cationic
polymerization at higher ratios initiated by Lewis acid. The selectivity to dimers of 97%
was obtained using 2 as catalyst with B/Pd molar ratio of 7. Similar curves of activity
versus cocatalyst/metal ratio is very common for the oligomerization and polymerization
of alkenes and the increase in activity with increasing cocatalyst/metal ratio is usually
explained by an equilibrium formation of the active complex from inactive precatalyst and
cocatalyst, i.e. by an increasing number of active species. The conversion of styrene with
various amine ligands (entries 1, 4, 8, 12, Table 7) seems to be similar. However, the
selectivity of the catalyst system was substantially affected by the nature of secondary
amine. The highest selecivity was obtained with morpholine ligand and the lowest
conversion was obtained with NH(nOct)2. As may be seen in Table 7, the order of the
decrease in selectivity parallels the increasing basicity [88] (electronic effect). Apparently,
the results indicate strongly that the amine molecule remains complexed to palladium
during the catalytic reaction.
Table 7
Dimerization of styrene

ACCEPTED MANUSCRIPT
Entry[a] Complex [B]0:[Pd]0 Selectivity[b] [%]
TON[c]
1
1
1
1
2
2
2
2
3
3
3
3
4
5
81
70
57
93
97
87
65
71
67
62
56
63
15200
25000
28400
10000
16500
17800
21800
13000
20000
25100
28000
16000
2
10
15
5
3
4
5
7
6
10
15
5
7
8
9
7
10
11
12
10
15
5
[a] BF3·OEt2 as co-catalyst was used, 5 h, nPd = 4.4 μmol, 1.3 mL CH2Cl2 + 2 mL C6H6 (internal
standard), t = 50°C [b] The crude products were analyzed by GC-FID. Trimers were also
detected (GC-MS). [c] molSt/molPd.
Norbornene polymerization. Norbornene (NB) and its derivatives are
representative cyclic olefin monomers which can be polymerized according to three
different schemes: metathesis, addition and isomerization mechanisms. These features
make norbornenes very attractive monomers for macromolecular design of polymers with
required properties. Each polymerization mechanism leads to a polymer type that is
different in structure and properties from the other. Palladium based catalysts usually
polymerize norbornene via a vinyl addition mechanism. Vinyl polynorbornene (PNB) has
received considerable attention owing to its optical, dielectric and mechanical properties
for technical application [89]. The catalytic performance of 1–3 in the polymerization of
norbornene in the presence of 25 eq BF3⋅OEt2 displayed moderate yields and activities in
the order of 105 gPNB mol Pd–1 h–1 (Table 8). Obtained PNB were soluble in toluene and 1,2,4-
trichlorobenzene. The structures of the Pd(II) complexes highly affected the molecular
weights PNB, which increases with the increasing of basicity of amine ligands [88]. The
palladium catalysts 4 with n-dioctylamine showed no activity in polymerization. Although

ACCEPTED MANUSCRIPT
different molecular weights were obtained, same NMR spectra were observed for those
polynorbornenes [90]. Thermogravimetric analyses (TGA/DSC) of the polymers show
typical high decomposition temperatures between 400–420°C.
Table 8
Polymerization of norbornene
[b]
[d]
Complex[a] [B]0/[Pd]0
Time [h] Yield [%]
Activity[c] Mv
1
2
3
4
25
25
25
25
4
4
4
4
56
51
31
—
1.3·105
1.2·105
0.7·105
—
2.3
1.2
3.5
—
[a] V0 = 10 mL, CH2Cl2, [NB]0/[Pd]0 = 10000, t = 25 °C, nPd = 1.33 μmol; [b] BF3·OEt2 as co-
catalyst was used; [c] In units of (g of PNB) (mol of Pd)−1 h−1; [d] Mv⋅10−6, obtained by
capillary viscosimetry in 1,2,4-trichlorobenzene using the Mark–Houwink coefficients α =
0.56, K = 7.78 ⋅ 10−4 dL/g [91,92]
Conclusions
New cationic palladium complexes containing secondary amine ligands were
prepared in good yields. An X-ray diffraction, NMR, IR and DFT study of
[Pd(acac)(morph)2][BF4] establishes the presence of hydrogen bonding between the
morpholine ligand and [BF4]− anion. We assume that in the obtained crystal of
[Pd(acac)(morph)2][BF4] in addition to the main structure, there are crystallographic
defects, in which the anion [BF4]− is at greater distances from the cation than in primary
structure. IR spectroscopy study showed that the ion-associates are present in the solution
of [Pd(acac)(morph)2][BF4], presumably consisting of a several pairs of cations and anions.
The tests of the [Pd(acac)(L)2]BF4 (L = morpholine, diethylamine, dibutylamine,
dioctylamine) complexes as catalyst in the polymerization of norbornene, dimerization of
styrene, and telomerization of 1,3-butadiene with diethylamine showed their moderate
activities in these reactions.

ACCEPTED MANUSCRIPT
Acknowledgments
The reported study was funded by RFBR, according to the research project No. 31
16-33-60115\15 mol_а_dk.
Supporting Information. Calculated and experimental NMR, IR spectral data,
Cartesian coordinates for the calculated species, and crystallographic data for 2 (in CIF
format).
References
[1]
[2]
W. Kaminsky, Polymerization catalysis, Catal. Today. 62 (2000) 23–34.
S. Mecking, Cationic nickel and palladium complexes with bidentate ligands for the C-C
linkage of olefins, Coord. Chem. Rev. 203 (2000) 325–351. doi:10.1016/S0010-
8545(99)00229-5.
[3]
[4]
[5]
[6]
[7]
[8]
D.S. McGuinness, Olefin Oligomerization via Metallacycles: Dimerization, Trimerization,
Tetramerization, and Beyond., Chem. Rev. 111 (2011) 2321–41. doi:10.1021/cr100217q.
J. Eisch, Fifty Years of Ziegler–Natta Polymerization: From Serendipity to Science. A Personal
Account, Organometallics. 31 (2012) 4917–4932. doi:dx.doi.org/10.1021/om300349x.
S.D. Ittel, L.K. Johnson, M.S. Brookhart, Late-metal catalysts for ethylene homo- and
copolymerization, Chem. Rev. 100 (2000) 1169–1203. doi:10.1021/cr9804644.
Z. Guan, C.S. Popeney, Recent Progress in Late Transition Metal -Diimine Catalysts for Olefin
Polymerization, in: Top. Organomet. Chem., 2009: pp. 179–220. doi:10.1007/3418_2008_7.
B.L. Goodall, Late Transition Metal Catalysts for the Copolymerization of Olefins and Polar
Monomers, in: Top. Organomet. Chem., 2009: pp. 159–178. doi:10.1007/3418_2008_6.
Z. Dong, Z. Ye, Hyperbranched polyethylenes by chain walking polymerization: synthesis,
properties, functionalization, and applications, Polym. Chem.
doi:10.1039/c1py00368b.
3
(2012) 286.
[9]
J.P. Mathew, A. Reinmuth, J. Melia, N. Swords, W. Risse, (η3-Allyl)palladium(II) and
Palladium(II) Nitrile Catalysts for the Addition Polymerization of Norbornene Derivatives
with Functional Groups, Macromolecules. 29 (1996) 2755–2763. doi:10.1021/ma9515285.
[10] H. V. Tran, R.J. Hung, T. Chiba, S. Yamada, T. Mrozek, Y. Hsieh, et al., Metal-Catalyzed Vinyl
Addition Polymers for 157 nm Resist Applications. 2. Fluorinated Norbornenes: Synthesis,
Polymerization, and Initial Imaging Results, Macromolecules. 35 (2002) 6539–6549.
[11] M. Arndt, M. Gosmann, Transition metal catalyzed polymerisation of norbornene, Polym.
Bull. 41 (1998) 433–440. http://www.springerlink.com/index/L6AL1W4FQX6GHA75.pdf.
[12] J.H. Choi, J.K. Kwon, T. V. RajanBabu, H.J. Lim, Highly Efficient Catalytic Dimerization of
Styrenes via Cationic Palladium(II) Complexes, Adv. Synth. Catal. 355 (2013) 3633–3638.
doi:10.1002/adsc.201300864.
[13] M.D. Walter, R.A. Moorhouse, S.A. Urbin, P.S. White, M.S. Brookhart, N. Carolina, Gamma-
agostic species as key intermediates in the vinyl addition polymerization of norbornene with
cationic (allyl)Pd catalysts: synthesis and mechanistic insights., J. Am. Chem. Soc. 131 (2009)
9055–69. doi:10.1021/ja9025598.
[14] M.D. Walter, P.S. White, M.S. Brookhart, Gamma-agostic interactions stabilize the
propagating species in the vinyl addition polymerization of norbornene., Chem. Commun.
(Camb). (2009) 6361–3. doi:10.1039/b916457j.
[15] K. Curran, W. Risse, M. Hamill, P. Saunders, J. Muldoon, R. Asensio de la Rosa, et al.,
Palladium(II)-Catalyzed Rearrangement and Oligomerization Reactions of cis
-
Bicyclo[4.2.0]oct-7-ene, Organometallics. 31 (2012) 882–889. doi:10.1021/om200877p.
[16] A. Chemtob, R.R.G. Gilbert, Catalytic Insertion Polymerization of Norbornene in
Miniemulsion, Macromolecules. 38 (2005) 6796–6805. doi:10.1021/ma050558x.
[17] L.K. Johnson, S. Mecking, M.S. Brookhart, Copolymerization of Ethylene and Propylene with

ACCEPTED MANUSCRIPT
Functionalized Vinyl Monomers by Palladium(II) Catalysts, J. Am. Chem. Soc. 118 (1996)
267–268. doi:10.1021/ja953247i.
[18] L.K. Johnson, C.M. Killian, M.S. Brookhart, New Pd(II)- and Ni(II)-Based Catalysts for
Polymerization of Ethylene and a-Olefins, J. Am. Chem. Soc. 117 (1995) 6414–6415.
[19] S. Mecking, L.K. Johnson, L. Wang, M.S. Brookhart, Mechanistic Studies of the Palladium-
Catalyzed Copolymerization of Ethylene and alpha-Olefins with Methyl Acrylate, J. Am. Chem.
Soc. 120 (1998) 888–899.
[20] E. Drent, R. van Dijk, R. van Ginkel, B. van Oort, R.I. Pugh, Palladium catalysed
copolymerisation of ethene with alkylacrylates: polar comonomer built into the linear
polymer chain, Chem. Commun. 31 (2002) 744–745. doi:10.1039/b111252j.
[21] A. Sen, T.W. Lai, Catalytic polymerization of acetylenes and olefins by
tetrakis(acetonitrile)palladium(II) ditetrafluoroborate, Organometallics. 1 (1982) 415–417.
doi:10.1021/om00062a038.
[22] A. Sen, T.-W. Lai, Catalysis by solvated transition-metal cations. Novel catalytic
transformations of alkenes by tetrakis(acetonitrile)palladium ditetrafluoroborate. Evidence
for the formation of incipient carbonium ions as intermediates, J. Am. Chem. Soc. 103 (1981)
4627–4629. doi:10.1021/ja00405a077.
[23] F. Blank, H. Scherer, C. Janiak, Journal of Molecular Catalysis Aꢀ: Chemical Oligomers and
soluble polymers from the vinyl polymerization of norbornene and 5-vinyl-2-norbornene
with cationic palladium catalysts, J. Mol. Catal.
doi:10.1016/j.molcata.2010.07.009.
A
Chem. 330 (2010) 1–9.
[24] Z. Jiang, A. Sen, Tailored cationic palladium(II) compounds as catalysts for highly selective
dimerization and polymerization of vinylic monomers: synthetic and mechanistic aspects,
Organometallics. 12 (1993) 1406–1415. doi:10.1021/om00028a066.
[25] Z. Jiang, A. Sen, Tailored cationic palladium(II) compounds as catalysts for highly selective
linear dimerization of styrene and linear polymerization of p-divinylbenzene, J. Am. Chem.
Soc. 112 (1990) 9655–9657. doi:10.1021/ja00182a044.
[26] W.J. Tao, J.F. Li, A.Q. Peng, X.L. Sun, X.H. Yang, Y. Tang, Water as an activator for
palladium(II)-catalyzed olefin polymerization, Chem. - A Eur. J. 19 (2013) 13956–13961.
doi:10.1002/chem.201300890.
[27] M.S. Winston, P.F. Oblad, J. a Labinger, J.E. Bercaw, Activator-free olefin oligomerization and
isomerization reactions catalyzed by an air- and water-tolerant Wacker oxidation
intermediate., Angew. Chem. Int. Ed. Engl. 51 (2012) 9822–4. doi:10.1002/anie.201206215.
[28] V.S. Tkach, D.S. Suslov, G. Myagmarsuren, F.K. Shmidt, Selective trimerization of ethylene in
the presence of a catalytic system based on bis(acetylacetonato)palladium and boron
trifluoride
etherate,
Russ.
J.
Appl.
Chem.
80
(2007)
1419–1423.
doi:10.1134/S1070427207080319.
[29] T. Tsuchimoto, S. Kamiyama, R. Negoro, E. Shirakawa, Y. Kawakami, Palladium-catalysed
dimerization of vinylarenes using indium triflate as an effective co-catalyst., Chem. Commun.
(Camb). 2 (2003) 852–853. doi:10.1039/b301280h.
[30] J. Peng, J. Li, H. Qiu, J. Jiang, K. Jiang, J. Mao, et al., Dimerization of styrene to 1,3-diphenyl-1-
butene catalyzed by palladium-Lewis acid in ionic liquid, J. Mol. Catal. A Chem. 255 (2006)
16–18. doi:10.1016/j.molcata.2006.03.058.
[31] V.S. Tkach, G. Myagmarsuren, D.S. Suslov, M. Mesyef, F.K. Shmidt, Palladium
carboxylate/boron trifluoride etherate catalyst system for the selective dimerization of
styrene, Catal. Commun. 8 (2007) 677–680. doi:10.1016/j.catcom.2006.08.029.
[32] G. Myagmarsuren, V.S. Tkach, F.K. Shmidt, M. Mohamad, D.S. Suslov, Selective dimerization of
styrene to 1,3-diphenyl-1-butene with bis(β-diketonato)palladium/boron trifluoride
etherate catalyst system, J. Mol. Catal.
A
Chem. 235 (2005) 154–160.
doi:10.1016/j.molcata.2005.03.034.
[33] D.S. Suslov, V.S. Tkach, M. V. Bykov, M. V. Belova, Selective dimerization of styrene to 1,3-
diphenylbutene-1 in the presence of [(acac)Pd(PAr3)2]BF4/BF3OEt2 catalytic systems, Pet.
Chem. 51 (2011) 157–163. doi:10.1134/S0965544111030157.
[34] J.A. Olson, T.A.P. Paulose, P. Wennek, J.W. Quail, S.R. Foley, Synthesis, structure and
norbornene polymerization activity of a bulky β-diketiminato palladium(II) complex, Inorg.
Chem. Commun. 11 (2008) 1297–1299. doi:10.1016/j.inoche.2008.08.006.

ACCEPTED MANUSCRIPT
[35] G. Myagmarsuren, K. Lee, O. Jeong, S. Ihm, Novel bis(acetylacetonate)palladium/boron
trifluoride etherate catalyst system for the polymerization of norbornene, Catal. Commun. 4
(2003) 615–619. doi:10.1016/j.catcom.2003.10.002.
[36] G. Myagmarsuren, K.S. Lee, O.Y. Jeong, S.K. Ihm, Homopolymerization of 5-alkyl-2-
norbornenes and their copolymerization with norbornene over novel Pd(acac)2/PPh3/BF
3OEt2
catalyst
system,
Polymer
(Guildf).
46
(2005)
3685–3692.
doi:10.1016/j.polymer.2005.02.112.
[37] D.S. Suslov, M. V. Bykov, P.A. Abramov, M. V. Pahomova, I.A. Ushakov, V.K. Voronov, et al.,
Pd(acac)(MeCN)2]BF4: air-tolerant, activator-free catalyst for alkenes dimerization and
polymerization, RSC Adv. 5 (2015) 104467–104471. doi:10.1039/C5RA24591E.
[38] D.S. Suslov, M. V. Bykov, M. V. Belova, P.A. Abramov, V.S. Tkach, Palladium(II)–
acetylacetonate complexes containing phosphine and diphosphine ligands and their catalytic
activities in telomerization of 1,3-dienes with diethylamine, J. Organomet. Chem. 752 (2014)
37–43. doi:10.1016/j.jorganchem.2013.11.017.
[39] D.S. Suslov, M.V. V Pahomova, P.A. Abramov, M. V. Bykov, V.S. Tkach, Cationic palladium(II)–
acetylacetonate complexes bearing α-diimine ligands as catalysts in norbornene
polymerization, Catal. Commun. 67 (2015) 11–15. doi:10.1016/j.catcom.2015.03.022.
[40] D.S. Suslov, M. V. Bykov, P.A. Abramov, M.V. Pakhomova, I.A. Ushakov, V.K. Voronov, et al.,
Synthesis, characterization, and application for addition polymerization of norbornene of
novel acetylacetonate bis(anilines) palladium (II) complexes, Inorg. Chem. Commun. 66
(2016) 1–4. doi:10.1016/j.inoche.2016.01.022.
[41] S. Okeya, H. Sazaki, M. Ogita, T. Takemoto, Y. Onuki, Y. Nakamura, et al., Reactions of the
bis(.BETA.-diketonato)palladium(II) complexes with various nitrogen bases., Bull. Chem. Soc.
Jpn. 54 (1981) 1978–1994. doi:10.1246/bcsj.54.1978.
[42] M.L. Chernyshev, V.S. Tkach, T.V.T. Dmitrieva, G. V. Ratovskii, S.V.S. Zinchenko, F.K. Shmidt,
Cationic Pd(II)-complex formation in the Pd(acac)2-Et2NH-BF3−OET2 system and its
activity in butadiene-amine telomerization, React. Kinet. Catal. Lett. 48 (1992) 291–294.
doi:10.1007/BF02070098.
[43] I. Yoshida, H. Kobayashi, K. Ueno, Differential thermal analysis of some divalent metal
chelates of 1,5-dialkylpentane-2,4-diones, J. Inorg. Nucl. Chem. 35 (1973) 4061–4070.
doi:10.1016/0022-1902(73)80394-X.
[44] F. Neese, The ORCA program system, Wiley Interdiscip. Rev. Comput. Mol. Sci. 2 (2012) 73–
78. doi:10.1002/wcms.81.
[45] A.D. Becke, Density-functional exchange-energy approximation with correct asymptotic
behavior, Phys. Rev. A. 38 (1988) 3098–3100.
[46] J.P. Perdew, Density-functional approximation for the correlation-energy of the
inhomogenous electron gas, Phys. Rev. B. 33 (1986) 8822–8824.
[47] K. Eichkorn, O. Treutler, H. Ohm, M. Ha
Coulomb potentials, Chem. Phys. Lett. 242 (1995) 652–660.
[48] M. Buhl, H. Kabrede, Geometries of transition-metal complexes from density-functional
theory, J. Chem. Theory Comput. (2006) 1282–1290.
http://pubs.acs.org/doi/abs/10.1021/ct6001187 (accessed August 14, 2012).
[49] M. Buhl, C. Reimann, D.A. Pantazis, T. Bredow, F. Neese, Geometries of Third-Row Transition-
̈ser, R. Ahlrichs, Auxiliary basis sets to approximate
̈
2
̈
Metal Complexes from Density-Functional Theory, J. Chem. Theory Comput. 4 (2008) 1449–
1459. doi:10.1021/ct800172j.
[50] C.J. Cramer, D.G. Truhlar, Density functional theory for transition metals and transition metal
chemistry., Phys. Chem. Chem. Phys. 11 (2009) 10757–10816. doi:10.1039/b907148b.
[51] M. Waller, H. Braun, N. Hojdis, M. Bü hl, Geometries of Second-Row Transition-Metal
Complexes from Density-Functional Theory, J. Chem. Theory Comput. 3 (2007) 2234–2242.
http://pubs.acs.org/doi/abs/10.1021/ct700178y (accessed August 9, 2012).
[52] M.J. Szabo, R.F. Jordan, A. Michalak, W.E. Piers, T. Weiss, S.-Y. Yang, et al., Polar
Copolymerization by a Palladium−Diimine-Based Catalyst. Influence of the Catalyst Charge
and Polar Substituent on Catalyst Poisoning and Polymerization Activity. A Density
Functional Theory Study, Organometallics. 23 (2004) 5565–5572. doi:10.1021/om049485g.
[53] S. Tobisch, T. Ziegler, Catalytic Oligomerization of Ethylene to Higher Linear α-Olefins
Promoted by the Cationic Group 4 [(η 5 -Cp-(CMe 2 -bridge)-Ph)M II (ethylene) 2 ] + (M = Ti,

ACCEPTED MANUSCRIPT
Zr, Hf) Active Catalysts: A Density Functional Investigation of the Influence of the Metal on
the, J. Am. Chem. Soc. 126 (2004) 9059–9071. doi:10.1021/ja048861l.
[54] F. Weigend, Accurate Coulomb-fitting basis sets for H to Rn., Phys. Chem. Chem. Phys. 8
(2006) 1057–65. doi:10.1039/b515623h.
[55] F. Weigend, R. Ahlrichs, Balanced basis sets of split valence, triple zeta valence and
quadruple zeta valence quality for H to Rn: Design and assessment of accuracy., Phys. Chem.
Chem. Phys. 7 (2005) 3297–305. doi:10.1039/b508541a.
[56] E. van Lenthe, A. van der Avoird, P.E.S. Wormer, Density functional calculations of molecular
hyperfine interactions in the zero order regular approximation for relativistic effects, J.
Chem.
Phys.
108
(1998)
4783–4796.
http://scholar.google.com/scholar?hl=en&btnG=Search&q=intitle:Density+functional+calcul
ations+of+molecular+hyperfine+interactions+in+the+zero+order+regular+approximation+f
or+relativistic+effects#0 (accessed August 9, 2012).
[57] E. van Lenthe, J.G. Snijders, E.J. Baerends, The zero-order regular approximation for
relativistic effects: The effect of spin–orbit coupling in closed shell molecules, J. Chem. Phys.
105
(1996)
6505–6516.
http://scholar.google.com/scholar?hl=en&btnG=Search&q=intitle:The+zero-
order+regular+approximation+for+relativistic+effects:+The+effect+of+spin?orbit+coupling
+in+closed+shell+molecules#0 (accessed August 9, 2012).
[58] E. van Lenthe, S. Faas, J.S. Snijders, Gradients in the ab initio scalar zeroth-order regular
approximation (ZORA) approach, Chem. Phys. Lett. 328 (2000) 107–112.
http://www.sciencedirect.com/science/article/pii/S0009261400008320 (accessed August
9, 2012).
[59] G.M. Sheldrick, Crystal structure refinement with SHELXL, Acta Crystallogr. Sect. C Struct.
Chem. 71 (2015) 3–8. doi:10.1107/S2053229614024218.
[60] C.B. Hübschle, G.M. Sheldrick, B. Dittrich, ShelXleꢀ: a Qt graphical user interface for SHELXL, J.
Appl. Crystallogr. 44 (2011) 1281–1284. doi:10.1107/S0021889811043202.
[61] Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA., (n.d.).
[62] J. van den Broeke, J.J.H. Heeringa, A. V Chuchuryukin, H. Kooijman, A.M. Mills, A.L. Spek, et al.,
Role of Cation−Anion Interactions in Ionic Complexes Containing [Pd{C 6 H 3 (CH 2 NMe 2 )
2 -2,6}(OH 2 )] + and [{Pd(C 6 H 3 (CH 2 NMe 2 ) 2 -2,6)} 2 (μ-Cl)] + Cations, Organometallics.
23 (2004) 2287–2294. doi:10.1021/om0303698.
[63] A.L. Seligson, W.C. Trogler, Cone angles for amine ligands. X-ray crystal structures and
equilibrium measurements for ammonia, ethylamine, diethylamine, and triethylamine
complexes with the [bis(dimethylphosphino)ethane]methylpalladium(II) cation, J. Am.
Chem. Soc. 113 (1991) 2520–2527. doi:10.1021/ja00007a028.
[64] V.S. Tkach, D.S. Suslov, G. Myagmarsuren, G. V. Ratovskii, A. V. Rohin, T. Felix, et al., An
effective route for the synthesis of cationic palladium complexes of general formula
[(Acac)PdL1L2]+A−,
J.
Organomet.
Chem.
693
(2008)
2069–2073.
doi:10.1016/j.jorganchem.2007.12.019.
[65] T.T. Da, D.B. Vu, N.H. Dinh, Synthesis and structure of some mixed cis -diamine complexes of
platinum(II) containing morpholine and another amine, J. Coord. Chem. 57 (2004) 485–496.
doi:10.1080/00958970410001689102.
[66] O.N. Shishilov, T.A. Stromnova, A. V. Churakov, L.G. Kuz’mina, I.A. Efimenko, Palladium
acetate complexes with morpholine and 4-methylmorpholine. The structure of
Pd(C4H9ON)2(OAc)2
·
2H2O, Russ. J. Inorg. Chem. 51 (2006) 574–580.
doi:10.1134/S0036023606040127.
[67] A. Behr, M. Becker, T. Beckmann, L. Johnen, J. Leschinski, S. Reyer, Telomerization: advances
and applications of a versatile reaction., Angew. Chem. Int. Ed. Engl. 48 (2009) 3598–614.
doi:10.1002/anie.200804599.
[68] P.W.N.M. Van Leeuwen, N.D. Clément, M.J.-L. Tschan, New processes for the selective
production
of
1-octene,
Coord.
Chem.
Rev.
255
(2011)
1499–1517.
doi:10.1016/j.ccr.2010.10.009.
[69] S. Díez-González, N. Marion, S.P. Nolan, N-heterocyclic carbenes in late transition metal
catalysis., Chem. Rev. 109 (2009) 3612–76. doi:10.1021/cr900074m.
[70] A. Pews-Davtyan, R. Jackstell, A. Spannenberg, M. Beller, Zwitterionic Phosphonium Ligands:

ACCEPTED MANUSCRIPT
Synthesis, Characteri–zation and Application in Telomerization of 1,3–Butadiene, Chem.
Commun. (2016). doi:10.1039/C6CC02747D.
[71] P.C.A.. P.C.A. Bruijnincx, R.. R. Jastrzebski, P.J.C.P.J.C.. b Hausoul, R.J.M.K.R.J.M.K.. Gebbink,
B.M.B.M.. Weckhuysen, Pd-Catalysed Telomerization of 1,3-Dienes with Multifunctional
Renewable Substrates: Versatile Routes for the Valorization of Biomass-Derived Platform
Molecules, in: B.P.C.A. Meier M.A.R. Weckhuysen B.M. (Ed.), Top Organomet Chem, Springer
Berlin Heidelberg, Berlin, Heidelberg, 2012: pp. 45–102. doi:10.1007/978-3-642-28288-1.
[72] M.J.-L.M.J.-L.. Tschan, J.-M.. López-Valbuena, Z.. Z. Freixa, H.H.. Launay, H.. H. Hagen, J.J.. Benet-
Buchholz, et al., Large P−P Distance Diphosphines and Their Monophosphine Analogues as
Ligands in the Palladium-Catalyzed Telomerization of 1,3-Butadiene and Methanol,
Organometallics. 30 (2011) 792–799. doi:10.1021/om100980m.
[73] P.J.C. Hausoul, A.N. Parvulescu, M. Lutz, A.L. Spek, P.C. a Bruijnincx, B.M. Weckhuysen, et al.,
Facile access to key reactive intermediates in the Pd/PR3-catalyzed telomerization of 1,3-
butadiene., Angew. Chem. Int. Ed. Engl. 49 (2010) 7972–5. doi:10.1002/anie.201003090.
[74] M.J.-L. Tschan, E.J. García-Suárez, Z. Freixa, H. Launay, H. Hagen, J. Benet-Buchholz, et al.,
Efficient bulky phosphines for the selective telomerization of 1,3-butadiene with methanol.,
J. Am. Chem. Soc. 132 (2010) 6463–73. doi:10.1021/ja100521m.
[75] A. Behr, J.. J. Leschinski, C.C.. Awungacha, S.S.. Simic, T.T.. Knoth, Telomerization of butadiene
with glycerol: reaction control through process engineering, solvents, and additives.,
ChemSusChem. 2 (2009) 71–76. doi:10.1002/cssc.200800197.
[76] R. Palkovits, I. Nieddu, R.J.M.K. Gebbink, B.M. Weckhuysen, Highly active catalysts for the
telomerization of crude glycerol with 1,3-butadiene., ChemSusChem. 1 (2008) 193–6.
doi:10.1002/cssc.200700147.
[77] N.D. Clément, L. Routaboul, A. Grotevendt, R. Jackstell, M. Beller, Development of palladium-
carbene catalysts for telomerization and dimerization of 1,3-dienes: from basic research to
industrial applications., Chem. Eur. J. 14 (2008) 7408–20. doi:10.1002/chem.200800858.
[78] A. Grotevendt, M. Bartolome, D.J. Nielsen, A. Spannenberg, R. Jackstell, K.J. Cavell, et al.,
Efficient catalysts for telomerization of butadiene with amines, Tetrahedron Lett. 48 (2007)
9203–9207. doi:10.1016/j.tetlet.2007.10.076.
[79] C.S.B.. Gomes, P.. Krishnamoorthy, L.C.. Silva, S.I.. Costa, P.T. Gomez, M. Jiménez-Tenorio, et
al., First examples of neutral and cationic indenyl nickel(II) complexes bearing arsine or
stibine ligands: Highly active catalysts for the oligomerisation of styrene, Dalt. Trans. 44
(2015) 17015–17019. doi:10.1039/c5dt02794b.
[80] H. Ma, Q. Sun, W. Li, J. Wang, Z. Zhang, Y. Yang, et al., Highly efficient Pd(acac)2/TFA
catalyzed head-to-tail dimerization of vinylarenes at room temperature, Tetrahedron Lett.
52 (2011) 1569–1573. doi:10.1016/j.tetlet.2011.01.056.
[81] D.W. Lee, C.S. Yi, Chain-Selective and Regioselective Ethylene and Styrene Dimerization
Reactions Catalyzed by a Well-Defined Cationic Ruthenium Hydride Complex: New Insights
on the Styrene Dimerization Mechanism, Organometallics. 29 (2010) 3413–3417.
doi:10.1021/om100468q.
[82] N.G. Grigor’eva, R.R. Talipova, a. N. Khazipova, S. V. Bubennov, B.I. Kutepov, U.M. Dzhemilev,
Dimerization of vinylarenes on zeolite catalysts, Pet. Chem. 49 (2009) 16–22.
doi:10.1134/S0965544109010046.
[83] S. Shimura, H. Miura, S. Tsukada, K. Wada, S. Hosokawa, M. Inoue, Highly Selective Linear
Dimerization of Styrenes by Ceria-Supported Ruthenium Catalysts, ChemCatChem. 4 (2012)
2062–2067. doi:10.1002/cctc.201200342.
[84] K. Liu, Y. Wang, P. Li, W. Cai, J. Xiang, Dimerization of styrenes catalyzed by
PhP(O)HOR/Mn(II)/Co(II)/O
doi:10.1016/j.catcom.2012.01.010.
[85] L. Ben tez Junquera, M.C. Puerta, P. Valerga, L. Ben t
2,
Catal.
Commun.
20
(2012)
107–110.
́
́
ez Junquera, M.C. Puerta, P. Valerga, et al.,
R-allyl nickel(II) complexes with chelating N-heterocyclic carbenes: Synthesis, structural
characterization, and catalytic activity, Organometallics. 31 (2012) 2175–2183.
doi:10.1021/om200937d.
[86] V. Khlebnikov, A. Meduri, H. Mueller-Bunz, T. Montini, P. Fornasiero, E. Zangrando, et al.,
Palladium Carbene Complexes for Selective Alkene Di- and Oligomerization, Organometallics.
31 (2012) 976–986. doi:10.1021/om201027y.

ACCEPTED MANUSCRIPT
[87] T. V. RajanBabu, N. Nomura, J. Jin, M. Nandi, H. Park, X. Sun, Heterodimerization of Olefins. 1.
Hydrovinylation Reactions of Olefins That Are Amenable to Asymmetric Catalysis, J. Org.
Chem. 68 (2003) 8431–8446. doi:10.1021/jo035171b.
[88] J.J.P. Furlong, E.S. Lewkowicz, N.S. Nudelman, Relative acidity and basicity of amines in
tetrahydrofuran and the influence of these factors on the carbonylation of lithium amides, J.
Chem. Soc. Perkin Trans. 2. (1990) 1461. doi:10.1039/p29900001461.
[89] F. Blank, C. Janiak, Metal catalysts for the vinyl/addition polymerization of norbornene,
Coord. Chem. Rev. 253 (2009) 827–861. doi:10.1016/j.ccr.2008.05.010.
[90] Spectra of the resulted polynorbornenes. 1HNMR: d = 0.5–3.0 ppm (m). 13C NMR: d = 29–52
ppm (m), (n.d.).
[91] Y. Huang, J. Chen, L. Chi, C. Wei, Z. Zhang, Z. Li, et al., Vinyl polymerization of norbornene with
bis(imino)pyridyl nickel(II) complexes, J. Appl. Polym. Sci. 112 (2009) 1486–1495.
doi:10.1002/app.29632.
[92] J. Zhang, W. Gao, X. Lang, Q. Wu, L. Zhang, Y. Mu, Ni(II) and Fe(II) complexes based on
bis(imino)aryl pincer ligands: synthesis, structural characterization and catalytic activities.,
Dalton Trans. 41 (2012) 9639–45. doi:10.1039/c2dt30778b.

ACCEPTED MANUSCRIPT
•
•
New acetylacetonate bis(secondary amine) palladium (II) complexes were
synthesized
XRD/IR/NMR/DFT studies shows hydrogen bonding between the amine ligands
and [BF4]–
•
•
•
Presence of pseudocrystalline structure in solution of complexes were assumed
Complexes are active in the telomerization of 1,3-butadiene with diethylamine
Complexes are active in the polymerization of norbornene, dimerization of
styrene