Synthesis, structures and catalytic activity of p-tolylimido rhenium(V) complexes incorporating quinoline-derived ligands

Article abstract of DOI:10.1016/j.ica.2016.04.030

p-Tolylimido rhenium(V) complexes, trans-(Cl,Cl)-[Re(p-NC₆H₄CH₃)Cl₂(4-MeO-quin-2-COO)(PPh₃)] (1), trans-(Br,Br)-[Re(p-NC₆H₄CH₃)Br₂(4-MeO-quin-2-COO)(PPh₃)]·2MeCN (2), trans-(Cl,Cl)-[Re(p-NC₆H₄CH₃)Cl₂(isoquin-1-COO)(PPh₃)] (3), trans-(Br,Br)-[Re(p-NC₆H₄CH₃)Br₂(isoquin-1-COO)(PPh₃)] (4), cis-(Cl,Cl)-[Re(p-NC₆H₄CH₃)Cl₂(4-MeO-quin-2-COO)(PPh₃)] (5), cis-(Br,Br)-[Re(p-NC₆H₄CH₃)Br₂(4-MeO-quin-2-COO)(PPh₃)]·MeOH (6), cis-(Cl,Cl)-[Re(p-NC₆H₄CH₃)Cl₂(isoquin-1-COO)(PPh₃)] (7) and cis-(Br,Br)-[Re(p-NC₆H₄CH₃)Br₂(isoquin-1-COO)(PPh₃)] (8), have been synthesized and characterized using X-ray analysis and spectroscopic methods (IR,¹H,¹³C and³¹P NMR, UV–Vis). To elucidate the structural, spectroscopic and bonding properties, the theoretical calculations at the DFT level were undertaken for 1, 3, 5 and 7. The synthesized complexes exhibited moderate activity in the oxidation of 1-phenylethanol and certain alkanes (n-heptane and methylcyclohexane) with tert-butyl hydroperoxide (TBHP) in acetonitrile. Chromatograms of products obtained from the alkanes indicated that a sufficient sterical hindrance exists around of the rhenium catalytic center.

Full text of DOI:10.1016/j.ica.2016.04.030

Inorganica Chimica Acta xxx (2016) xxx–xxx
Contents lists available at ScienceDirect
Inorganica Chimica Acta
journal homepage: www.elsevier.com/locate/ica
Synthesis, structures and catalytic activity of p-tolylimido rhenium(V)
complexes incorporating quinoline-derived ligands
b
c,d,
I. Gryca a, B. Machura a, , Lidia S. Shul’pina , Georgiy B. Shul’pin
⇑
⇑
a Department of Crystallography, Institute of Chemistry, University of Silesia, 9th Szkolna St., 40-006 Katowice, Poland
b Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, ulitsa Vavilova, dom 28, Moscow 119991, Russia
c Semenov Institute of Chemical Physics, Russian Academy of Sciences, ulitsa Kosygina, dom 4, Moscow 119991, Russia
d Plekhanov Russian University of Economics, Stremyannyi pereulok, dom 36, Moscow 117997, Russia
a r t i c l e i n f o
a b s t r a c t
Article history:
p-Tolylimido rhenium(V) complexes, trans-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)] (1),
trans-(Br,Br)-[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)(PPh3)]ꢀ2MeCN (2), trans-(Cl,Cl)-[Re(p-NC6H4CH3)
Cl2(isoquin-1-COO)(PPh3)] (3), trans-(Br,Br)-[Re(p-NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (4), cis-(Cl,Cl)-[Re
(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)] (5), cis-(Br,Br)-[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)
(PPh3)]ꢀMeOH (6), cis-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] (7) and cis-(Br,Br)-[Re(p-
NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (8), have been synthesized and characterized using X-ray analysis
and spectroscopic methods (IR, 1H, 13C and 31P NMR, UV–Vis). To elucidate the structural, spectroscopic
and bonding properties, the theoretical calculations at the DFT level were undertaken for 1, 3, 5 and 7. The
synthesized complexes exhibited moderate activity in the oxidation of 1-phenylethanol and certain alkanes
(n-heptane and methylcyclohexane) with tert-butyl hydroperoxide (TBHP) in acetonitrile. Chromatograms
of products obtained from the alkanes indicated that a sufficient sterical hindrance exists around of the
rhenium catalytic center.
Received 19 February 2016
Received in revised form 13 April 2016
Accepted 18 April 2016
Available online xxxx
This paper is dedicated to the memory of
Professor Rino Michelin.
Keywords:
Rhenium imido complexes
X-ray structure
DFT calculations
Alcohols
tert-Butyl hydroperoxide
Oxidation
Ó 2016 Published by Elsevier B.V.
1. Introduction
of CAH bonds of aromatic and saturated hydrocarbons [4]. In
recent years, there has been also a renewed interest in high-valent
Transition metal complexes containing multiple bonds to oxy-
gen and nitrogen atoms attract widespread scientific attention.
These compounds have been postulated as the active intermedi-
ates in biologically relevant transformations [1] and they were suc-
cessfully employed as effective catalysts in numerous industrial
processes [2]. The high-oxidation state of the catalyst allows the
reaction to be carried out under ‘‘open-flask” conditions, without
the need for rigorous exclusion of air and moisture.
Particular attention has been drawn to high-oxidation state rhe-
nium complexes. The rhenium(VII) derivative methylrhenium tri-
oxide in combination with hydrogen peroxide has found wide
use in oxidation catalysis. Rhenium complexes have become
important catalysts for oxidation of various organic compounds
[3] including olefins, ketones and alcohols. High-valent oxo-rhe-
nium complexes were also successfully employed in the activation
imido rhenium complexes [5]. Imido (NR2ꢁ) ligands are isoelec-
tronic to oxo (O2ꢁ) ions. Compared to oxo complexes, however,
imido complexes seems to be more versatile due to an opportunity
to tune the steric and electronic properties of the complex by
changing the nitrogen substituent [6].
Recently [7], we reported the synthesis and properties of sev-
eral imidorhenium(V) complexes incorporating uninegative biden-
tate N,O-chelating ligands. The studies demonstrated that
compounds [Re(p-NC6H4CH3)X3(PPh3)2] (X = Cl, Br) are excellent
starting materials for the syntheses of these compounds and that
the reaction course of [Re(p-NC6H4CH3)X3(PPh3)2] with N,O-donor
chelating ligands is governed by many factors, including the type
of the ligand and experimental conditions. The complexes [Re
(p-NC6H4CH3)X2(pyz-2-COO)(PPh3)] and [Re(p-NC6H4CH3)X2(ind-
3-COO)(PPh3)] were found to catalyze oxidation of alkanes with
H2O2 and tert-butyl hydroperoxide (TBHP) and of alcohols with
TBHP, whereas [Re(p-NC6H4CH3)X2(py-2-COO)(PPh3)] exhibited
catalytic activity in the syntheses of N-substituted ethyl glycine
esters from ethyl diazoacetate and amines. Noteworthy, the cat-
alytic activity of these systems may be influenced by different
⇑
Corresponding authors at: Semenov Institute of Chemical Physics, Russian
Academy of Sciences, ulitsa Kosygina, dom 4, Moscow 119991, Russia
(G.B. Shul’pin).
E-mail addresses: basia@ich.us.edu.pl (B. Machura), Shulpin@chph.ras.ru
(G.B. Shul’pin).
http://dx.doi.org/10.1016/j.ica.2016.04.030
0020-1693/Ó 2016 Published by Elsevier B.V.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

2
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
regio-isomers (cis-(X,X) or trans-(X,X)) of [Re(p-NC6H4CH3)
X2(NAO)(PPh3)]. In the present studies, we used another bidentate
chelating carboxylate ligands incorporating quinoline or isoquino-
line ring, namely isoquinoline-1-carboxylic acid (iqcH) and
4-methoxy-2-quinolinecarboxylic acid (mqcH).
isolated from the reactions carried out in methanolic solution.
These findings are consistent with those reported for [Re(p-
NC6H4CH3)X2(py-2-COO)(PPh3)] [7f]. Different reactivity pattern
in acetonitrile and methanol is attributed to formation of
trans-(X,X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2] in the reaction of
mer-[Re(p-NC6H4CH3)X3(PPh3)2] with methanol and subsequent
reaction of trans-(X,X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2] with
N-heterocyclic acid. In acetonitrile, the first step seems to
concern the substitution of the labile X ligand trans to the imido
group in mer-[Re(p-NC6H4CH3)X3(PPh3)2] by the oxygen atom of
N,O-donor ligand, possibly with the proton transfer to the
released Xꢁ. In the next step, the uncoordinated N-donor atom of
N,O-donor ligand substitutes the equatorial phosphine to form
neutral imido complex trans-(X,X)-[Re(p-NC6H4CH3)X2(N-O)
(PPh3)2]. In methanol, the labile X ligand trans to the imido group
in mer-[Re(p-NC6H4CH3)X3(PPh3)2] can be substituted by both
oxygen atom of N,O-donor ligand and the methoxy ion coming
from methanol. As for [Re(p-NC6H4CH3)X2(py-2-COO)(PPh3)], the
reactions of trans-(X,X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2] with N-
heterocyclic acids (4-MeO-quin-2-COOH and isoquin-1-COOH)
resulted in the formation of cis isomers (Scheme 2).
N
COOH
Isoquinoline-1-carboxylic acid
(iqcH)
OCH3
N
COOH
4-Methoxy-2-quinolinecarboxylic
acid (mqcH)
All complexes 1–8 show high stability toward air and moisture
both in the solid state and in solution for several weeks at ambient
temperature. They are moderately soluble in polar solvents such as
acetonitrile, acetone, chloroform, dichloromethane and methanol,
as well as non-polar solvents as benzene.
Herein, we present the structural, spectroscopic and catalytic
properties of the following imido complexes: trans-(Cl,Cl)-
[Re(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)] (1), trans-(Br,Br)-
[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)(PPh3)]ꢀ2MeCN (2),
trans-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] (3),
trans-(Br,Br)-[Re(p-NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (4),
cis-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)] (5),
cis-(Br,Br)-[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)(PPh3)]ꢀMeOH
(6), cis-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] (7) and
cis-(Br,Br)-[Re(p-NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (8). To get
2.2. IR and 1H NMR spectra
The IR spectra of 1–8 are dominated by very strong band that
occurs in range 1684–1698 cmꢁ1 assigned to
m
as(CO2) stretching
s(CO2) bands found in the range
High values of (CO2) = as(CO2)– s(CO2)
mode and two strong
m
1241–1330 cmꢁ1
.
D
m
m
m
(350–430 cmꢁ1) reflect a unidentate coordination mode of the car-
boxylate group in compounds 1–8 [8]. For both trans-(X,X) and cis-
(X,X) isomers of [Re(p-NC6H4CH3)X2(4-MeO-quin-2-COO)(PPh3)]
and [Re(p-NC6H4CH3)X2(isoquin-1-COO)(PPh3)], these frequencies
are very similar and they are not distinctive for molecular structure
a
better understanding of the structural, spectroscopic and
bonding properties, the theoretical calculations at the DFT level
were undertaken for 1, 3, 5 and 7. The catalytic potential of the
complexes in oxidations was studied.
determination. The vibrations m(ReANC6H4CH3) in 1–8 are difficult
to identify experimentally as they are mixed with mC@N and mPAC
modes of PPh3 and 4-MeO-quin-2-COOꢁ and isoquin-1-COOꢁ
ligands [7b–d,9].
2. Results and discussion
In the 1H NMR spectra of the examined compounds distinctive
signals corresponding to the alkyl protons of the p-tolylimido group
occur in the range 2.30–2.21 ppm. The signals of alkyl protons of the
4-methoxy-2-quinolinecarboxylate ligand of 1, 2, 5 and 6 complexes
occur in the range 4.32–4.14 ppm. The protons of PPh3 appear in the
range 7.71–7.11 ppm. The signals of 4-methoxyquinoline and
isoquinoline hydrogens, that appear in the range 8.29–6.95 and
9.50–7.73 ppm, respectively, are shifted downfield in comparison
with the free ligands (8.08–6.49 ppm for 4-methoxyquinoline
ligand and 8.96–7.65 ppm for isoquinoline ligand).
The coordination of the phosphine was additionally confirmed
by 31P NMR spectroscopy. As expected, the single phosphorus sig-
nals, observed for 1–8 in the range 25.42–25.81 ppm, are down-
field from uncoordinated triphenylphosphine (ꢁ6 ppm). The lack
of paramagnetic broadening or shifts of resonances in the 1H
NMR spectra of 1–8 is in agreement with diamagnetism of the
complexes.
2.1. Synthesis of the complexes
The complexes 1–8 were prepared in good yield by ligand
exchange reactions of mer-[Re(p-NC6H4CH3)X3(PPh3)2] or trans-(X,
X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2]
with
4-methoxy-2-
quinolinecarboxylic acid (4-MeO-quin-2-COOH) and isoquinoline-
1-carboxylic acid (isoquin-1-COOH), respectively (Scheme 1). The
synthetic strategy of 1–8 is presented in Scheme 1.
As in the previous studies [7c,f,g], the reactions of mer-[Re(p-
NC6H4CH3)X3(PPh3)2] with N-heterocyclic acids (4-MeO-quin-2-
COOH and isoquin-1-COOH) were independent on molar ratio of
the metal precursor to ligand. Even when excess of the acid was
used, only monosubstituted compounds of general formula [Re
(p-NC6H4CH3)X2(NAO)(PPh3)] were obtained. Formation of
isomeric forms (trans–cis) of [Re(p-NC6H4CH3)X2(4-MeO-quin-2-
COO)(PPh3)]
and
[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)]
were found to be solvent-dependent. Refluxing of mer-[Re
(p-NC6H4CH3)X3(PPh3)2] with 4-MeO-quin-2-COOH and isoquin-
1-COOH in acetonitrile led to the compounds [Re(p-NC6H4CH3)
X2(NAO)(PPh3)] (NAO = 4-MeO-quin-2-COO or isoquin-1-COO)
with halide ions in trans arrangement, whereas the mixture of cis
and trans isomers of [Re(p-NC6H4CH3)X2(4-MeO-quin-2-COO)
(PPh3)] and [Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] were
2.3. Molecular structures
A definite proof for the structures of 1–8 is provided by the X-ray
diffraction data. The crystallographic parameters of 1–8 are sum-
marized in Table 1. The perspective drawings of the asymmetric
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
3
CH3
CH3
CH3
N
OH
N
OH
mer-[Re(p-NC6H4CH3)X3(PPh3)2]
trans isomer
N
N
+
N
Ph3P
X
reflux in
CH3CN
X
Ph3P
X
X
reflux in
CH3OH
X
X
PPh3
N
X = Cl, Br
Re
Re
Re
N
N
O
O
O
mixture of trans and cis isomers
CH3
CH3
1
2
3
4
+
+
+
+
5
6
7
8
1 (X = Cl)
2 (X = Br)
3 (X = Cl)
4 (X = Br)
N
Ph3
P
X
X
N
X
Re
N
Ph3
P
X
Re
N
C
OMe
O
O
C
O
O
CH3
+ CH3OH
cis isomer
N
OH
trans-(X,X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2]
N
X
X
PPh3
Re
N
O
CH3
CH3
5 (X = Cl)
6 (X = Br)
7 (X = Cl)
8 (X = Br)
N
X
X
PPh3
N
X
PPh3
Re
Re
N
N
C
O
X
OMe
O
O
C
O
Scheme 1. Formation of complexes 1–8.
CH3
CH3
CH3
CH3
CH3
N
OH
N
OH
N
N
N
N
+
Ph3P
X
Ph3P
X
N
Ph3P
X
X
X
X
-HX
Ph3P
X
-HX
-PPh3
X
Ph3P
X
X
Re
Re
Re
Re
Re
reflux in
CH3OH
reflux in
CH3CN
PPh3
PPh3
PPh3
N
OCH3
O
PPh3
O
O
X
N
N
trans isomer
CH3
N
CH3
N
Ph3P
X
X
X
X
PPh3
Re
Re
O
N
N
O
trans isomer
cis isomer
Scheme 2. Proposed mechanism for the formation of cis or trans-(X,X)-[Re(p-NC6H4CH3)X2(N–O)(PPh3)] (N–O = 4-MeO-quin-2-COOꢁ or isoquin-1-COOꢁ).
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

4
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
units of 1–8 are presented in Fig. 1, and the selected bond distances
and angles are collected in Table 2.
As presented in Tables S3 and S4, the PBE1PBE method gives
acceptable deviations between the experimental and theoretical
geometric data. The ReANimido bond lengths are reproduced with
small deviations ranging from +0.001 to +0.005 Å. Also, the exper-
imental and calculated spectra of 1, 3, 5 and 7 are in reasonable
All reported complexes show a six-coordinate rhenium atom
with distorted octahedral geometries defined by the p-
methylphenylimido group, two halide ions, the phosphorus atom
of PPh3 molecule, and the carboxylate chelate ligand 4-MeO-
quin-2-COOꢁ (in 1, 2, 5 and 6) or isoquin-1-COOꢁ (in 3, 4, 7 and 8).
The principal distortions result from the presence of multiple
p-methylphenylimido ligand and bite angles of bidentate ligands
4-MeO-quin-2-COOꢁ or isoquin-1-COOꢁ coordinating through the
nitrogen and oxygen atoms (with the bite angle of 74.81(10) in 1,
75.6(2) in 2, 74.62(17) in 3, 75.2(3) in 4, 74.53(12) in 5, 74.64(13)
in 6, 74.32(19) in 7 and 74.75(14)° in 8). For all examined complexes
1–8, the ReANimido bond lengths (from 1.700(4) Å in 8 to 1.726(7) Å
in 2) fall in the range 1.67–1.74 Å typical for mononuclear com-
plexes of rhenium(V) having [Re„NR]3+ core, and reflect the
expected triple Re„N bond. The triply bonded p-methylphenylim-
ido ligand forces the metal nonbonding d electrons to lie in the plane
agreement (Fig. S1). The calculated mas(CO2) and ms(CO2) are almost
identical for both trans-(X,X) and cis-(X,X), despite the different
molecular symmetry of these isomers (1814, 1333 and
1306 cmꢁ1 for 1 and 1806, 1331 and 1306 cmꢁ1 for 5; 1808,
1312 and 1287 cmꢁ1 for 3 and 1800, 1312 and 1287 cmꢁ1 for 7).
In comparison with the experimental data, these values are shifted
to higher frequencies by ꢂ7%, which is an usual feature for this
approach (Fig. S1). The calculated
m(ReANC6H4CH3) frequencies
appear at 1553, 1439 and 1062 cmꢁ1 for 1, 1555, 1453 and
1065 cmꢁ1 for 3, 1556, 1453 and 1065 cmꢁ1 for 5 and 1554, 1453
and 1065 cmꢁ1 for 7. As mentioned above, experimentally these
vibrations are difficult to identify as the m(ReANC6H4CH3) stretches
are mixed with mC@N and mPAC modes of PPh3 and isoquin-1-COOꢁ
and 4-MeO-quin-2-COOꢁ ligands [5d,e,12].
perpendicular to the Re„NR bond axis. Due to accessible
tion from the rhenium ion, triphenylphosphine molecule and
-acceptor N-heterocyclic ring of the bidentate ligand adopt cis dis-
p-dona-
To get additional insight into the bond characteristics in the
reported compounds, a natural bond orbital (NBO) study was per-
formed. The occupancy and composition of the calculated ReAN(2)
natural bond orbitals (NBOs) are given in Table S5. For complexes
p
position with respect to the linear Re„NR core. The presence of the
harder oxygen atom of the chelating N,O-donor ligand in the trans
position to the ion p-NC6H4CH3 is justified by trans-influence of
the imido group. The complexes 1–4 were found to be the trans iso-
mer of[Re(p-NC6H4CH3)X2(NAO)(PPh3)], whereas the halide ligands
of 5–8 occupy cis positionsto eachother. As previously reported [7g],
the energy difference between trans-(X,X) and cis-(X,X) isomers of
[Re(p-NC6H4CH3)X2(NAO)(PPh3)] is remarkably small indicating
that their formation is kinetically rather than thermodynamically
controlled. Also, a search in the CSD (The Cambridge Structural
Database, Version 5.36) confirms that both isomeric forms are
almost equally observed among [Re(NR)X2(NAO)(PPh3)]
complexes. The most important structural parameters of [Re
(p-NR)X2(NAO)(PPh3)] are gathered in Table S1.
The ReAN, ReAX, ReAO and ReAO bond lengths of 1–8 are within
the expected range for [Re(NR)X2(NAO)(PPh3)] complexes (Tables 2
and S1; see also Refs. [7,9a,10]). In all reported complexes the ReAN
bonds are significantly longer than the ReAO distances. This effect
occurs in complexes of metal ions in high oxidation state and can
be understood in terms of Pearson’s hard-soft acid–base theory. As
hard Lewis acid ReV ion forms stronger bonds with oxygen rather
than with the comparatively softer base nitrogen donor. Impor-
tantly, the interatomic distance between the rhenium atom and
the carboxylate oxygen atom in 1–8 is almost equal to an ideal single
ReAO bond length (ca. 2.04 Å) [11], indicating lack of delocalization
in the RN„ReAO unit. The ReANimidoACimido bond angles of 173.38
(11)° in 1, 176.1(3)° in 2, 178.2(2)° in 3, 178.0(3)° in 4, 170.39(17)° in
5, 169.73(18)° in 6, 167.3(2)° in 7 and 168.40(16)° in 8 agree with a
linear coordination mode of the arylimido ligands, and these values
are typical of phenyl imido ligands in high oxidation state com-
plexes, in which the metal is relatively electron-deficient and some
1, 5 and 7, the results of NBO point to the existence of one
r and
two natural ReANimido orbitals, whereas for complex 3 NBO
p
results reveal only two ReANR natural bond orbitals. Both orbitals
of 3 result from overlapping of the empty dxy and dyz rhenium orbi-
tals with the occupied px and pz orbitals of the deprotonated nitro-
gen of the imido ligand, and they are of
ReANR natural orbital indicates a conceivable predominant Cou-
lomb-type ReAligand interaction. and bonds of 1, 5 and 7 as
well as bonds of 3 are strongly polarized toward the nitrogen
p character. Lack of r
r
p
p
atom; the nitrogen contributions to these bonds are between 57%
and 73%. The hybridization at rhenium shows clearly that d contri-
bution dominates the metal bonding in
r
and
p
ReANimido bonds.
atomic
For bonds, the oxygen atom employs pure or quasi pure p
p
orbitals. The nature of ReANimido bonds is in agreement with the
results obtained in previous works regarding analysis of the bond-
ing nature of imido rhenium(V) complexes.
For all complexes, the Wiberg bond indices of the ReAN(2) are
almost three times larger than those of Re(1)AN(1) and Re(1)AO
(1). The values 2.069 for 1, 2.085 for 3, 2.051 for 5, and 2.056 for
7 are consistent with a formal Re@N double-bond description, with
a partial triple-bond character. The WBIs of the Re(1)AO(1) and Re
(1)AN(1) bonds are in the range of 0.5–0.6. A greater degree of
covalent character is evidenced by WBIs for bonds between the
central ion and halide or triphenylphosphine ligand (Table S6).
Schematic representation of the energy of the highest occupied
and lowest unoccupied orbitals of 1, 3, 5 and 7 is presented in
Fig. S2. The contours of the selected frontier orbitals of 1, 3, 5
and 7 are depicted in Fig. 2, whereas their percentage compositions
are gathered in Table S7. The HOMO of all examined complexes
presents significant metallic character (60%), and its energy is
almost unaffected by the nature of the carboxylate ligand and sym-
metry of the compound. Except for 3, the HOMO is constituted by
rhenium dxy orbital in antibonding relation to the occupied p orbi-
tal of Cl ligand and occupied p orbital of carboxylate oxygen atom.
What is more, the HOMO orbitals of 1, 5 and 7 present a similar
p-bonding between the imido nitrogen atom and the metal is likely.
Finally, no extraordinary differences in terms of bond lengths and
angles can be noticed between trans-(X,X)-[Re(p-NC6H4CH3)X2
(N-COO)(PPh3)] and cis-(X,X)-[Re(p-NC6H4CH3)Cl2(N-COO)(PPh3)]
compounds. No intermolecular interactions with enough strength
to govern crystal packing or molecule conformation were found in
the structures of 1–8 except for weak intra- and intermolecular
CAHꢀ ꢀ ꢀCl, CAHꢀ ꢀ ꢀN type and CAHꢀ ꢀ ꢀO contacts (Table S2).
percentage contribution, 60% d(Re), 30%
for 1, 60% d(Re), 25% (Cl) and 15% (NAO) for 5 and 50% d(Re),
35% (Cl) and 15% (NAO) for 7. In contrast, the HOMO of 3 is a
p(Cl) and 10% p(NAO)
p
p
p
p
2.4. DFT calculations
nonbonding combination of rhenium dxy orbital p chloride orbitals.
To a large extent, the H-1 of 1, 5 and 7 can be considered as pRe„NR
For further understanding structural and bonding properties of
the imido rhenium(V) complexes, the calculations at the DFT level
were undertaken for 1, 3, 5 and 7.
orbitals. It consists of d of rhenium and p orbitals of the imido
p
ligand. For both isomers, H-1 molecular orbital is contributed by
p chloride orbitals. The H-1 orbital of 3 is mainly contributed by
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

Table 1
Crystal data and structure refinement for 1–8 complexes.
1
2
3
4
5
6
7
8
Empirical formula
Formula weight
T (K)
C
36H30Cl2N2O3PRe
C40H36Br2N4O3PRe
997.72
293.0(2)
0.71073
monoclinic
C2/c
C35H28Cl2N2O2PRe
796.66
293.0(2)
0.71073
monoclinic
P21
C35H28Br2N2O2PRe
885.58
298.0(1)
0.71073
monoclinic
P21
C36H30Cl2N2O3PRe
826.69
293.0(2)
0.71073
monoclinic
P21/n
C37H34Br2N2O4PRe
947.65
293.0(2)
0.71073
monoclinic
P21/c
C35H28Cl2N2O2PRe
796.66
293.0(2)
C35H28Br2N2O2PRe
885.58
298.0(1)
826.69
293.0(2)
0.71073
monoclinic
P21/n
k (Å)
0.71073
0.71073
Crystal system
Space group
Unit cell dimensions
a (Å)
b (Å)
c (Å)
triclinic
triclinic
ꢀ
ꢀ
P1
P1
9.8196(3)
22.2897(7)
14.8141(4)
37.1104(5)
15.2308(6)
14.6871(12)
9.2754(4)
17.1246(6)
10.4910(4)
9.3436(5)
17.1874(6)
10.5612(6)
9.9530(4)
20.4722(9)
17.3166(8)
9.9416(4)
20.5902(9)
17.8865(12)
7.9061(4)
11.7360(6)
17.8939(10)
92.530(5)
91.168(5)
105.156(5)
1600.10(15)
2
8.0690(3)
11.7247(4)
17.6547(5)
91.703(3)
90.309(3)
104.982(3)
1612.60(9)
2
a
(°)
b (°)
91.064(2)
106.587(3)
110.856(5)
110.906(6)
105.233(4)
105.971(6)
c
(°)
V (Å3)
3241.88(17)
4
1.694
4.002
1632
7956.0(7)
8
1.666
5.145
3904
1557.17(10)
2
1.699
4.160
784
1584.38(14)
2
1.856
6.442
856
3404.5(3)
4
1.613
3.811
1632
3520.0(3)
4
1.788
5.810
1848
Z
Dcalc(mg/m3)
1.654
4.049
784
1.824
6.329
856
Absorption coefficient (mmꢁ1
F(000)
)
Crystal size (mm)
h range for data collection (°) 3.30–25.00
Index ranges
0.102 ꢃ 0.131 ꢃ 0.204 0.324 ꢃ 0.162 ꢃ 0.016 0.007 ꢃ 0.126 ꢃ 0.154 0.069 ꢃ 0.089 ꢃ 0.147 0.025 ꢃ 0.106 ꢃ 0.248 0.154 ꢃ 0.071 ꢃ 0.019 0.082 ꢃ 0.055 ꢃ 0.031 0.029 ꢃ 0.048 ꢃ 0.290
3.38–25.00
ꢁ43 6 h 6 44,
ꢁ18 6 k 6 14,
ꢁ17 6 l 6 17
20402
3.34–25.00
ꢁ11 6 h 6 11,
ꢁ20 6 k 6 20,
ꢁ12 6 l 6 12
10907
3.45–25.00
ꢁ10 6 h 6 11,
ꢁ20 6 k 6 20,
ꢁ9 6 l 6 12
7919
3.42–25.00
ꢁ11 6 h 6 11,
ꢁ15 6 k 6 24,
ꢁ17 6 l 6 20
19116
3.60–25.00
ꢁ9 6 h 6 11,
ꢁ24 6 k 6 21,
ꢁ21 6 l 6 17
11373
3.42–25.00
ꢁ96 h 69,
ꢁ13 6 k 6 13,
ꢁ21 6 l 6 21
12799
3.46–25.00
ꢁ9 6 h < 6 9,
ꢁ13 6 k 6 13,
ꢁ20 6 l 6 20
14375
ꢁ11 6 h 6 11,
ꢁ26 6 k 6 26,
ꢁ16 6 l 6 17
19405
Reflections collected
Independent reflections (Rint
Completeness to 2h = 50° (%) 99.7
)
5688 (0.0357)
6984 (0.0897)
99.7
5307 (0.0389)
99.7
5315 (0.0293)
99.7
5971 (0.0402)
99.7
5888 (0.0394)
94.9
5616 (0.1109)
99.6
5663 (0.0526)
99.8
Maximum and minimum
0.402 and 1.000
0.238 and 1.000
0.503 and 1.000
0.580 and 1.000
0.638 and 1.000
0.628 and 1.000
0.512 and 1.000
0.305 and 1.000
transmission
Data/restraints/parameters
Goodness-of-fit (GOF) on F2
5688/0/408
1.030
6984/0/464
0.985
5307/1/389
0.993
5315//1/389
1.114
5971/0/408
1.056
5888/0/428
1.009
5616/0/389
1.062
5663/0/389
0.992
Final R indices [I > 2
r
(I)]
R1 = 0.0243,
wR2 = 0.0482
R1 = 0.0339,
wR2 = 0.0506
0.638 and ꢁ0.504
R1 = 0.0670,
wR2 = 0.1657
R1 = 0.0941,
wR2 = 0.1858
4.260 and ꢁ1.712
R1 = 0.0300,
wR2 = 0.0493
R1 = 0.0393,
wR2 = 0.0513
0.643 and ꢁ0.599
R1 = 0.0325,
wR2 = 0.0728
R1 = 0.0384,
wR2 = 0.0864
1.094 and ꢁ0.564
R1 = 0.0327,
wR2 = 0.0748
R1 = 0.0495,
wR2 = 0.0820
1.273 and ꢁ0.834
R1 = 0.0343,
wR2 = 0.0688
R1 = 0.0568,
wR2 = 0.0751
0.912 and ꢁ0.541
R1 = 0.0507,
wR2 = 0.0810
R1 = 0.0844,
wR2 = 0.0867
1.712 and ꢁ1.399
R1 = 0.0360,
wR2 = 0.0720
R1 = 0.0467,
wR2 = 0.0756
1.797 and ꢁ1.080
R indices (all data)
Largest different peak and
hole (e Åꢁ3
)

6
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
Fig. 1. The molecular structures of 1–8. Displacement ellipsoids are drawn at 50% probability.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
7
Table 2
The experimental bond lengths (Å) and angles (°) for 1A8.
1 (X = Cl)
2 (X = Br)
3 (X = Cl)
4 (X = Br)
5 (X = Cl)
6 (X = Br)
7 (X = Cl)
8 (X = Br)
Bond lengths
Re(1)AN(2)
Re(1)AO(1)
Re(1)AN(1)
Re(1)AX(1)
Re(1)AX(2)
Re(1)AP(1)
1.712(3)
2.050(2)
2.184(3)
2.3897(9)
2.4045(9)
2.4205(9)
1.726(7)
2.029(6)
2.195(7)
2.427(2)
2.5514(10)
2.5523(10)
1.703(5)
2.045(4)
2.134(5)
2.3971(16)
2.4134(17)
2.4332(16)
1.712(8)
2.044(6)
2.120(8)
2.5455(10)
2.5632(10)
2.428(2)
1.707(4)
2.054(3)
2.169(4)
2.3679(12)
2.3976(13)
2.4464(13)
1.718(4)
2.051(3)
2.173(4)
2.5200(6)
2.5467(7)
2.4541(15)
1.711(5)
2.055(4)
2.108(6)
2.370(2)
2.401(2)
2.4514(18)
1.700(4)
2.044(3)
2.105(4)
2.5131(6)
2.5507(6)
2.4574(13)
Bond angles
N(2)ARe(1)AO(1)
N(2)ARe(1)AN(1)
O(1)ARe(1)AN(1)
N(2)ARe(1)AX(1)
O(1)ARe(1)AX(1)
N(1)ARe(1)AX(1)
N(2)ARe(1)AX(2)
O(1)ARe(1)AX(2)
N(1)ARe(1)AX(2)
X(1)ARe(1)AX(2)
N(2)ARe(1)AP(1)
O(1)ARe(1)AP(1)
N(1)ARe(1)AP(1)
X(1)ARe(1)AP(1)
X(2)ARe(1)AP(1)
C(30)AN(2)ARe(1)
173.38(11)
101.37(11)
74.81(10)
99.02(9)
86.38(8)
88.31(7)
92.36(9)
81.92(8)
84.05(7)
167.36(3)
93.45(9)
90.34(7)
165.14(7)
90.37(3)
94.44(3)
171.2(2)
176.1(3)
108.3(3)
75.6(2)
178.2(2)
105.7(2)
74.62(17)
95.82(16)
86.02(12)
84.33(13)
92.22(16)
85.98(13)
85.70(14)
168.58(6)
93.13(16)
86.60(11)
161.22(13)
94.20(5)
93.45(5)
176.5(4)
C(29)
178.0(3)
104.0(3)
75.2(3)
94.2(2)
87.52(18)
84.1(2)
91.7(2)
86.42(18)
85.8(2)
69.30(4)
93.9(2)
86.86(18)
162.1(2)
95.21(6)
93.26(6)
174.2(6)
C(29)
170.39(17)
100.67(16)
74.53(12)
98.57(14)
86.92(9)
160.43(10)
99.69(14)
88.26(10)
84.57(10)
88.75(5)
90.59(14)
81.68(10)
95.38(10)
87.91(5)
169.56(4)
177.0(4)
169.73(18)
100.47(17)
74.64(13)
97.94(14)
87.75(9)
161.22(11)
100.39(15)
88.19(11)
84.04(11)
89.05(2)
90.86(15)
80.82(11)
95.97(12)
87.41(4)
168.57(4)
176.6(4)
167.3(2)
95.1(2)
168.40(16)
96.15(17)
74.75(14)
98.24(13)
91.37(9)
165.20(10)
98.90(13)
87.40(10)
83.77(11)
90.60(2)
93.17(14)
80.48(10)
93.69(11)
88.95(3)
167.85(4)
177.9(4)
74.32(19)
100.24(19)
90.83(14)
164.36(15)
99.25(19)
86.97(14)
84.69(16)
89.73(9)
93.35(19)
80.62(13)
94.01(15)
88.25(7)
167.39(6)
177.5(5)
C(29)
94.3(2)
86.20(17)
85.79(19)
94.5(2)
85.62(17)
83.21(19)
167.64(4)
93.5(2)
82.64(18)
158.19(19)
90.85(6)
97.28(6)
176.0(7)
C(29)
p
orbitals of phosphine ligand and p chloride orbitals and contains
Some parameters obtained in the oxidation of n-heptane with
tert-butyl hydroperoxide (TBHP) are collected in Table 3 and
Fig. 3. Chromatograms of selected experiments are shown in
Fig. S4. The oxidation with TBHP catalyzed by the rhenium com-
plexes of cis-1,2-dimethylcyclohexane proceeds non-stereoselec-
tively. Thus, parameter trans/cis for the oxidation catalyzed by 2
was 0.8 that is close to unity. Thus, we can conclude that selectivity
parameters testify that alkanes are oxidized by the systems under
discussion with the participation of tert-butoxy radicals. The oxida-
tion of CAH bonds with TBHP involves the interaction of the alkane
with tert-butoxy radical tert-BuOꢀ. It is noteworthy that the regios-
electivity parameter for the oxidation catalyzed by complexes 2–6
is similar to that found by us previously in the reaction with the
systems containing a strongly hindered reaction center. These cat-
alytic systems are, particularly, the tetracopper(II) triethanolami-
nate complex [OꢄCu4{N(CH2CH2O)3}4(BOH)4][BF4]2/TBHP and
only small amount of pRe„NR orbital. The H-2 of 1, 3, 5 and 7 is
mostly contributed by orbitals of the chelating ligand, whereas
the other high-lying occupied molecular orbitals are predomi-
nately localized on PPh3 ligand. The LUMO, LUMO + 1 and LUMO
+ 2 are delocalized on the rhenium atom (dxz and dyz orbitals)
and
p-antibonding orbitals of the imido and carboxylate ligands.
The dyz and dxy rhenium orbitals bear antibonding character
towards the p nitrogen orbitals of the imido ligand. To a ⁄large
p
extent, these molecular orbitals can be considered as pRe„NR
orbitals.
In order to assign UV–Vis absorption bands and better under-
stand the spectroscopic characteristics of the complexes 1, 3, 5
and 7, TDDFT calculations have been carried out. The experimental
and calculated electronic spectra of 1–4 are compared in Fig. S3.
Tables S8–S11 present the most important electronic transitions
calculated with the TDDFT method assigned to the observed
absorption bands of 1, 3, 5 and 7, respectively.
The low-energy absorption bands, observed at 818, 615 and
448 nm for 1, 759, 606 and 460 nm for 3, 668 and 457 nm for 5
and 685, 576 and 464 nm for 7, are contributed by transitions
d/
(p-tol)/p⁄(L) for 3. They can be seen as mixed d?d (Ligand Field;
LF), (L)/
(X)?d (Ligand–Metal Charge Transfer; LMCT), d?p⁄(L)
(Metal–Ligand Charge Transfer; MLCT) and
(L)?p⁄(L) (Ligand–
dinuclear manganese complex [Mn2(R-LMe2R)2( -O)2]3+(PF6)3
l
(where LMe2R is 1-(2-hydroxypropyl)-4,7-dimethyl-1,4,7-triazacy-
clononane)/oxalic acid/TBHP are shown in Fig. 3. It can be clearly
seen that in rhenium-catalyzed oxidations reactivity of CAH bonds
in position C(2) is two times higher in comparison with the analo-
gous value for position C(4). It is noteworthy that the chro-
matograms of reaction mixtures obtained in the oxidation of
methylcyclohexane (MCH) testify that a strong shielding of posi-
tions 2 of the cyclohexane ring takes place (Fig. S5).
p(Cl)/p p
(L)?d/p⁄(L)/p⁄(p-tol) for 1, 5 and 7 and d/ (Cl)?d/p⁄
p
p
p
Ligand Charge Transfer; LLCT) or a delocalized MLLCT (metal–
ligand-to-ligand CT) character can be assigned as the origin for
these transitions. The intense bands in high energy region of 1, 3,
5 and 7 are largely attributed to ligand–metal charge transfer
(LMCT), ligand–ligand charge transfer (LLCT) and intraligand transi-
tions (IL).
The synthesized rhenium complexes did not exhibit high cat-
alytic activity in oxidation of 1-phenylethanol with TBHP in ace-
tonitrile. The initial rates for the most active complexes are
collected in Table S12.
3. Conclusions
Complexes trans-(X,X)-[Re(p-NC6H4CH3)X2(N-O)(PPh3)2] and
cis-(X,X)-[Re(p-NC6H4CH3)X2(N-O)(PPh3)2] incorporating quinoline
or isoquinoline carboxylate bidentate ligands (NAO) were synthe-
sized, characterized and checked as catalysts in oxidations of alka-
nes and 1-phenylethanol. Formation of isomeric forms (trans–cis)
of [Re(p-NC6H4CH3)X2(4-MeO-quin-2-COO)(PPh3)] and [Re(p-NC6-
H4CH3)Cl2(isoquin-1-COO)(PPh3)] were found to be solvent-dependent.
2.5. A study of catalytic activity in oxidations with peroxides
We checked the catalytic activity of prepared rhenium com-
plexes in oxidation of organic compounds with peroxides. The
complexes turned out to be inactive in oxidation of alkanes and
alcohols with hydrogen peroxide.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

8
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
Molecular orbitals of 1
H-3
H-2
H-1
HOMO
LUMO
L+1
L+2
L+3
Molecular orbitals of 3
H-3
H-2
H-1
HOMO
LUMO
L+1
L+2
L+3
Molecular orbitals of 5
H-3
H-2
H-1
HOMO
L+3
LUMO
L+1
L+2
Molecular orbitals of 7
H-3
H-2
H-1
HOMO
L+3
LUMO
L+1
L+2
Fig. 2. The contours of the selected frontier orbitals of 1, 3, 5 and 7.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
9
Table 3
kinetically rather than thermodynamically. Some complexes
exhibited a moderate activity in regioselective oxidations with
TBHP.
Oxidation of n-heptane catalyzed by certain rhenium complexes prepared in the
present work.a
Entry
Catalyst
TON
Parameter C(2):C(3):C(4)
1
2
3
4
5
2
3
4
5
6
10
11
16
12
14
1.0:0.57:0.48
1.0:0.57:0.43
1.0:0.60:0.44
1.0:0.68:0.46
1.0:0.55:0.45
4. Experimental
4.1. Materials
The reagents used to the synthesis were commercially available
and they were used without further purification. The complexes
mer-[Re(p-NC6H4CH3)X3(PPh3)2] (X = Cl, Br) and trans-[Re(p-NC6-
H4CH3)X2(OMe)(PPh3)2] (X = Cl, Br) were prepared according to
the literature methods [7f,14].
a
Conditions. Catalyst, 2 ꢃ 10ꢁ4 M; TBHP (70% aqueous), 0.45 M, HNO3, 0.05 M;
2 h, 60 °C. Concentration of isomeric heptanoles present in the reaction solution
was measured after reduction of a sample with PPh3 (see Fig. S4). The TON is
number of moles of product produced per one mol of catalyst. Parameters C(1):C
(2):C(3):C(4) are relative normalized reactivities of H atoms at carbon atoms C(1), C
(2), C(3) and C(4) of n-heptane or n-octane chain.
4.2. Physical measurements
The findings enhance our understanding of the structural prefer-
ences of the imido rhenium(V) complexes with uninegative
N,O-donor ligands. The X-ray studies and NBO analysis confirm a
linear coordination mode of the p-NC6H4CH3 ligand and triple bond
between the rhenium and the imido ligand. The results clearly
indicate that the molecular structure of [Re(p-NC6H4CH3)X2(N-O)
(PPh3)2] compounds is predominantly governed by multiply
bonded imido ligand, and their isomeric preferences are controlled
Infrared spectra were recorded on a Nicolet iS5 spectropho-
tometer in the spectral range 4000–400 cmꢁ1 with the samples
in the form of potassium bromide pellets. Electronic spectra were
measured on a spectrophotometer Lab Alliance UV–VIS 8500 in
the range 1100ꢅ190 nm in acetonitrile solution. The 1H NMR, 13C
NMR and 31P NMR spectra were recorded (298 K) on Bruker
Advance 500 NMR spectrometer at a resonance frequency of
500 MHz for 1H NMR spectra, 125 MHz for 13C NMR spectra and
Fig. 3. Regioselectivity profiles for the oxidation of n-heptane (a and b) and n-octane (c–f) with TBHP catalyzed by various metal complexes: trans-(Cl,Cl)-[Re(p-NC6H4CH3)
Cl2(isoquin-1-COO)(PPh3)] (complex 3; this work) (a); tetracopper(II) triethanolaminate complex [OꢄCu4{N(CH2CH2O)3}4(BOH)4][BF4]2.(Ref. [13a]): reaction with n-heptane
(b) and n-octane (c); Cu(H3L3)(NCS) where ligand H4L3 is N,N,N0,N0-tetrakis-(2-hydroxyethyl)ethylenediamine (Ref. [13b]) (d); [(PhSiO1.5
)12(CuO)4(NaO0.5)4] (Ref. [13c]) (e);
[Mn2(R-LMe2R)2( -O)2]3+(PF6)3, where LMe2R is 1-(2-hydroxypropyl)-4,7-dimethyl-1,4,7-triazacyclononane (Ref. [13d]) (f).
l
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

10
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
162 MHz for 31P NMR using DMSO-d6 as solvent and TMS as an
internal standard. Elemental analyses (C, H, N) were performed
on a Perkin-Elmer CHN-2400 analyser.
4.3.3. trans-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] (3)
[Re(p-NC6H4CH3)Cl3(PPh3)2] (0.48 g) and isoquinoline-1-car-
boxylic acid (0.10 g) yielded 322 mg of 3; yield 75%. C35H28Cl2N2-
O2PRe (796.66 g/mol): Calc. C, 52.77; H, 3.54; N, 3.52; found: C,
52.85; H, 3.51; N, 3.48%.
IR (KBr; m
/cmꢁ1): 3058(w), 1684(vs), 1617(w), 1589(w), 1560
4.3. Preparation of complexes 1–4
(w), 1482(w), 1449(w), 1436(m), 1359(w), 1322(w), 1313(w),
1278(m), 1246(s), 1209(w), 1185(w), 1167(sh), 1154(m), 1142
(sh), 1097(w), 1089(w), 1014(w), 1005(w), 997(w), 886(w), 829
(m), 817(sh), 799(w), 760(w), 751(w), 742(w), 701(sh), 691(s),
670(w), 618(w), 568(w), 525(s), 511(m), 501(m), 448(w) and 428
(w).
Starting complex mer-[Re(p-NC6H4CH3)X3(PPh3)2] (0.54 mmol)
was added to the corresponding N-heterocyclic carboxylic acid
(0.60 mmol) in acetonitrile (60 mL) and the reaction mixture was
refluxed for 6 h. The resulting solution was reduced in volume to
10 mL and allowed to cool to room temperature. A crystalline pre-
cipitate of 1–4 was filtered off and dried in the air. X-ray quality
brown crystals of 1–4 were obtained by slow recrystallization from
acetonitrile.
1H NMR (400 MHz, DMSO-d6, ppm): d = 8.37 (d, 1H, 6.3 Hz),
8.27 (d, 1H, 8.1 Hz), 8.03 (t, 1H, 7.8 Hz), 7.91 (t, 2H, 8.0 Hz),
7.66–7.58 (m, 6H), 7.49 (dd, 12H, 14.9, 6.8 Hz), 7.28 (d, 2H,
8.1 Hz) and 2.29 (s, 3H).
13C NMR (125 MHz, DMSO-d6): d = 164.8, 159.8, 156.0, 155.0,
154.1, 144.7, 142.0, 140.3, 139.3, 134.6, 134.5, 131.7, 131.6,
131.1, 128.9, 128.8, 127.9, 127.7, 126.4, 124.2, 122.3, 122.0, 121.4
and 22.3 ppm.
4.3.1. trans-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)]
(1)
[Re(p-NC6H4CH3)Cl3(PPh3)2] (0.48 g) and 4-methoxy-2-quino-
linecarboxylic acid (0.12 g) yielded 357 mg of complex 1; yield
80%. C36H30Cl2N2O3PRe (826.69 g/mol): Calc. C, 53.30; H, 3.66; N,
3.39; found: C, 52.83; H, 3.64; N, 3.38%.
31P NMR (DMSO-d6): d = 25.55 ppm.
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 759 (165);
IR (KBr; m
/cmꢁ1): 3050(w), 1686(vs), 1586(s), 1518(m), 1482
606 (801); 460 (5680); 326 (22616); 235 (101216); 199 (184009).
(w), 1434(m), 1386(w), 1366(s), 1351(sh), 1328(m), 1301(w),
1285(w), 1274(w), 1258(w), 1229(w), 1171(w), 1122(m), 1101
(sh), 1092(w), 1032(w), 1015(w), 998(m), 960(w), 898(w), 855
(w), 827(w), 804(w), 790(w), 769(m), 748(m), 706(sh), 693(m),
647(w), 619(w), 574(w), 530(s), 503(m) and 445(w).
4.3.4. trans-(Br,Br)-[Re(p-NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (4)
[Re(p-NC6H4CH3)Br3(PPh3)2] (0.52 g) and isoquinoline-1-car-
boxylic acid (0.10 g) yielded 360 mg of 4; yield 75%. C35H28Br2N2-
O2PRe (885.58 g/mol): Calc. C, 47.47; H, 3.19; N, 3.16, found: C,
46.83; H, 3.10; N, 3.25%.
1H NMR (400 MHz, DMSO-d6, ppm): d = 8.29 (d, 1H, 10.0 Hz),
8.12 (d, 1H, 7.8 Hz), 7.77 (t, 1H, 7.6 Hz), 7.69 (s, 1H), 7.65–7.57
(m, 6H), 7.50 (d, 10H, 6.3 Hz), 7.44 (d, 2H, 8.1 Hz), 7.13 (d, 2H,
8.1 Hz), 4.32 (s, 3H) and 2.21 (s, 3H).
IR (KBr; m
/cmꢁ1): 3059(w), 1685(vs), 1640(sh), 1617(sh), 1590
(w), 1482(w), 1436(m), 1358(w), 1278(m), 1246(s), 1210(sh),
1186(w), 1167(sh), 1154(m), 1142(sh), 1096(w), 1089(sh), 1014
(w), 997(w), 887(w), 829(m), 818(sh), 799(w), 760(w), 751(w),
742(w), 691(s), 670(sh), 568(w), 525(s), 511(m), 500(sh), 488(sh),
455(w), 448(w), 420(w).
13C NMR (125 MHz, DMSO-d6): d = 166.9, 166.1, 155.9, 148.4,
145.3, 143.6, 143.1, 141.7, 139.2, 138.6, 136.6, 134.7, 132.0,
131.8, 131.7, 131.1, 129.8, 129.3, 128.8, 126.7, 124.7, 123.5,
122.0, 121.9, 102.2, 58.1, 22.2 ppm.
1H NMR (400 MHz, DMSO-d6, ppm): d = 9.50 (d, 1H, 8.9 Hz),
8.38 (d, 1H, 6.1 Hz), 8.26 (d, 1H, 8.4 Hz), 8.06–7.99 (m, 1H), 7.92
(d, 2H, 6.5 Hz), 7.71–7.61 (m, 6H), 7.56 (d, 2H, 8.0 Hz), 7.50 (s,
9H), 7.29 (d, 2H, 7.8 Hz) and 2.30 (s, 3H).
31P NMR (DMSO-d6): d = 25.69 ppm.
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 818 (114);
615 (146); 448 (611); 411 (640); 324 (6237); 298 (5709); 232
(29497).
13C NMR (125 MHz, DMSO-d6): d = 167.1, 154.2, 142.5, 142.3,
141.5, 140.4, 140.1, 139.6, 138.9, 134.7, 134.0, 133.6, 131.9,
131.6, 131.4, 131.2, 130.0, 129.5, 129.3, 129.0, 128.9, 128.7,
128.2, 127.7, 127.6, 126.3, 124.6, 124.1, 121.9 and 22.5 ppm.
31P NMR (DMSO-d6): d = 25.81 ppm.
4.3.2. trans-(Br,Br)-[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)(PPh3)]ꢀ
2MeCN (2)
[Re(p-NC6H4CH3)Br3(PPh3)2] (0.52 g) and 4-methoxy-2-quino-
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 752 (238);
linecarboxylic acid (0.12 g) yielded 430 mg of 2; yield 80%. C40H36
-
605 (1087); 461 (15708); 321 (57025); 278 (56757); 234
Br2N4O3PRe (997.72 g/mol): Calc. C, 48.15; H, 3.64; N, 5.61; found:
C, 49.13; H, 3.66; N, 5.55%.
(174820); 197 (303334).
IR (KBr;
m
/cmꢁ1): 3051(w), 1698(vs), 1588(s), 1519(w), 1482
4.4. Preparation of complexes 5–8
(w), 1458(w), 1435(m), 1391(m), 1365(s), 1329(m), 1274(sh),
1257(w), 1227(w), 1185(w), 1171(w), 1155(w), 1132(sh), 1115
(m), 1091(w), 1031(w), 1019(w), 996(w), 889(w), 861(w), 827
(sh), 815(sh), 804(w), 790(w), 768(w), 753(w), 746(w), 694(m),
618(w), 565(w), 529(s), 511(w), 494(w) and 456(w).
1H NMR (400 MHz, DMSO-d6, ppm): d = 8.32 (d, 1H, 8.1 Hz),
8.06 (d, 1H, 8.7 Hz), 7.78 (t, 1H, 7.7 Hz), 7.71–7.59 (m, 8H), 7.50
(d, 11H, 8.0 Hz), 7.15 (d, 2H, 8.1 Hz), 4.32 (s, 3H), 2.24 (s, 3H) and
2.07(s, 6H).
Complex
trans-(X,X)-[Re(p-NC6H4CH3)X2(OMe)(PPh3)2]
(0.54 mmol) was added to the corresponding N-heterocyclic car-
boxylic acid (0.60 mmol) in methanol (60 mL) and the reaction
mixture was refluxed for 6 h. The resulting solution was reduced
in volume to 10 mL and allowed to cool to room temperature. A
crystalline precipitate of mixture of 5–8 was filtered off and dried
in the air. The mixture of X-ray quality green crystals of 5–8 was
obtained by slow recrystallization from methanol.
13C NMR (125 MHz, DMSO-d6): d = 167.3, 163.7, 147.9, 142.9,
133.9, 133.5, 132.7, 132.6, 132.5, 131.9, 130.7, 129.4, 129.3,
129.2, 125.3, 123.5, 122.8, 121.6, 118.6, 101.8, 58.4, 20.88 and
1.62 ppm.
4.4.1. cis-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)] (5)
[Re(p-NC6H4CH3)Cl3(PPh3)2] (0.48 g) and 4-methoxy-2-quino-
linecarboxylic acid (0.12 g) yielded 357 mg of product; yield 80%.
The crystals of 1 and 5 were manually separated using a micro-
scope and they were collected in 45% and 35% yield, respectively.
31P NMR (DMSO-d6): d = 25.64 ppm.
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 765 (263);
620 (397); 462 (1517); 422 (2337); 328 (21693); 300 (22741);
C36H30Cl2N2O3PRe (826.69 g/mol): Calc. C, 52.30; H, 3.66; N, 3.39;
199 (217102).
found: C, 52.61; H, 3.15; N, 3.57%.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
11
IR (KBr;
m
/cmꢁ1): 3054(w), 1686(vs), 1616(w), 1589(s), 1561
31P NMR (DMSO-d6): d = 25.42 ppm.
UV–Vis (MeCN; kmax [nm] (
; [dm3 molꢁ1 cmꢁ1])): 685 (167);
576 (277); 464 (2660); 353 (5688); 317 (21199); 279 (58217);
(sh), 1521(w), 1481(w), 1461(w), 1433(w), 1392(m), 1364(s),
1330(w), 1262(w), 1189(w), 1173(w), 1164(w), 1131(sh), 1117
(m), 1093(w), 1021(w), 996(w), 953(w), 888(w), 859(w), 804(w),
791(w), 756(w), 692(w), 528(m), 501(w) and 447(w).
e
240 (71837); 191 (127721).
1H NMR (400 MHz, DMSO-d6, ppm): d = 8.35 (d, 1H, 8.3 Hz),
7.96 (d, 1H, 8.9 Hz), 7.82(t, 1H, 7.6 Hz), 7.66–7.85 (m, 1H), 7.29–
7.19 (m, 6H), 7.19–7.11 (m, 9H), 7.05 (d, 2H, 8.3 Hz), 6.99 (d, 2H,
8.4 Hz), 6.95 (s, 1H), 4.14 (s, 3H), 2.23 (s, 3H).
4.4.4. cis-(Br,Br)-[Re(p-NC6H4CH3)Br2(isoquin-1-COO)(PPh3)] (8)
[Re(p-NC6H4CH3)Br3(PPh3)2] (0.52 g) and isoquinoline-1-car-
boxylic acid (0.10 g) yielded 360 mg of product; yield 75%. The
crystals of 4 and 8 were manually separated using a microscope
13C NMR (125 MHz, DMSO-d6): d = 168.2, 166.9, 154.1, 149.8,
143.9, 141.8, 134.7, 134.6, 134.1, 134.0, 133.1, 131.7, 131.4,
130.6, 129.8, 129.4, 129.2, 129.0, 128.9, 128.8, 128.8, 128.7,
126.6, 125.7, 123.3, 122.9, 122.1, 101.3, 100.7, 57.9, 57.1, 22.3 ppm.
31P NMR (DMSO-d6): d = 25.74 ppm.
and they were collected in 40% and 35% yield, respectively. C35H28-
Br2N2O2PRe (885.58 g/mol): Calc. C, 47.47; H, 3.19; N, 3.16; found:
C, 46.98; H, 3.21; N, 3.25%.
IR (KBr; m
/cmꢁ1): 3059(w), 1685(vs), 1618(w), 1590(w), 1481
(w), 1436(m), 1364(w), 1278(w), 1241(m), 1186(w), 1171(w),
1156(m), 1141(w), 1092(w), 1016(w), 998(w), 888(w), 821(m),
800(w), 751(m), 707(sh), 692(m), 673(w), 528(s), 507(w), 498
(w), 456(w), 443(w), 436(w).
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 668 (278);
457 (3422); 330 (13924); 305 (13294); 234 (57933); 190
(130151).
1H NMR (400 MHz, DMSO-d6, ppm): d = 9.50 (d, 1H, J = 8.7 Hz),
8.38 (d, 1H, J = 6.2 Hz), 8.27 (d, 1H, J = 8.3 Hz), 8.02 (t, 1H,
J = 7.9 Hz), 7.91 (t, 2H, J = 7.1 Hz), 7.70–7.60 (m, 6H), 7.55 (t, 2H,
J = 9.2 Hz), 7.50 (s, 9H), 7.29 (d, 2H, J = 8.0 Hz), 2.30 (s, 3H).
13C NMR (125 MHz, DMSO-d6): d = 163.1, 142.4, 141.2, 140.4,
139.3, 138.5, 138.2, 136.9, 134.7, 134.6, 134.0, 133.6, 132.6,
132.5, 131.9, 131.7, 131.6, 131.4, 130.9, 130.7, 129.4, 129.3,
129.2, 128.8, 128.7, 127.8, 126.4, 126.3, 125.6, 124.2, 123.3,
121.9, 119.4, 119.3, 22.4 ppm.
4.4.2. cis-(Br,Br)-[Re(p-NC6H4CH3)Br2(4-MeO-quin-2-COO)
(PPh3)].MeOH (6)
[Re(p-NC6H4CH3)Br3(PPh3)2] (0.52 g) and 4-methoxy-2-quino-
linecarboxylic acid (0.12 g) yielded 430 mg of product; yield 80%.
The crystals of 2 and 6 were manually separated using a micro-
scope and they were collected in 45% and 35% yield, respectively.
C
37H34Br2N2O4PRe (947.65 g/mol): Calc. C, 46.90; H, 3.62; N,
2.96; found: C, 47.11; H, 3.59; N, 2.95%.
IR (KBr;
/cmꢁ1): 3049(w), 1686(vs), 1587(s), 1518(m), 1481
m
31P NMR (DMSO-d6): d = 25.79 ppm.
(w), 1453(w), 1433(m), 1386(w), 1365(s), 1329(m), 1302(w),
1283(w), 1257(w), 1186(sh), 1179(w), 1172(w), 1117(m), 1091
(w), 1033(w), 1015(w), 997(m), 959(w), 952(w), 888(w), 855(w),
827(w), 803(w), 789(w), 768(w), 754(m), 705(sh), 692(m), 647
(w), 619(w), 573(w), 529(s), 501(m), 458(w), 444(w).
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 761 (89);
587 (225); 464 (1960); 327 (5489); 233 (29378); 190 (59931).
4.5. Crystal structure determination and refinement
1H NMR (400 MHz, DMSO-d6, ppm): d = 8.32 (d, 1H, 8.1 Hz),
8.06 (d, 1H, 8.9 Hz), 7.78 (t, 1H, 7.6 Hz), 7.67 (dd, 8H, 16.4,
8.3 Hz), 7.49 (d, 11H, 8.2 Hz), 7.15 (d, 2H, 8.3 Hz), 4.32 (s, 3H),
2.24 (s, 3H), 2.07 (s, 3H).
The X-ray intensity data of 1–8 were collected on a Gemini A
Ultra diffractometer equipped with Atlas CCD detector and gra-
phite monochromated Mo K
a radiation (k = 0.71073 Å) at room
temperature. Details concerning crystal data and refinement are
given in Tables S1 and S2. Lorentz, polarization and empirical
absorption correction using spherical harmonics implemented in
SCALE3 ABSPACK scaling algorithm were applied [15]. The struc-
tures were solved by the Patterson method and subsequently com-
pleted by the difference Fourier recycling. All the non-hydrogen
atoms were refined anisotropically using full-matrix, least-squares
technique. The hydrogen atoms were treated as ‘‘riding” on their
parent carbon atoms and assigned isotropic temperature factors
equal 1.2 (non-methyl) and 1.5 (methyl) times the value of equiv-
alent temperature factor of the parent atom. The methyl groups
were allowed to rotate about their local threefold axis. SHELXS97
and SHELXL97 programs were used for all the calculations [16].
Atomic scattering factors were those incorporated in the computer
programs.
13C NMR (125 MHz, DMSO-d6): d = 164.9, 163.9, 149.1, 144.0,
134.1, 134.0, 133.6, 132.8, 132.5, 131.9, 131.8, 131.4, 130.8,
130.7, 129.7, 129.2, 129.1, 129.0, 128.9, 127.0, 126.4, 125.7,
125.4, 123.3, 122.4, 121.6, 109.9, 101.2, 57.8, 22.3 ppm.
31P NMR (DMSO-d6): d = 25.79 ppm.
UV–Vis (MeCN; kmax [nm] (e
; [dm3 molꢁ1 cmꢁ1])): 666 (81);
557 (128); 462 (2831); 402 (7997); 352 (13138); 289 (17527);
250 (33505); 210 (86171).
4.4.3. cis-(Cl,Cl)-[Re(p-NC6H4CH3)Cl2(isoquin-1-COO)(PPh3)] (7)
[Re(p-NC6H4CH3)Cl3(PPh3)2] (0.48 g) and isoquinoline-1-car-
boxylic acid (0.10 g) yielded 322 mg of product; yield 75%. The
crystals of 3 and 7 were manually separated using a microscope
and they were collected in 40% and 35% yield, respectively.) C35
28Cl2N2O2PRe (796.66 g/mol): Calc. C, 52.77; H, 3.54; N, 3.52;
found: C, 52.85; H, 3.51; N, 3.48%.
IR (KBr;
/cmꢁ1): 3059(w), 1690(vs), 1654(sh), 1641(sh), 1591
-
H
4.6. Computational details
m
(m), 1551(w), 1481(m), 1434(s), 1356(w), 1320(w), 1275(w),
1241(m), 1187(w), 1169(w), 1155(m), 1141(w), 1096(m), 1015
(w), 999(w), 888(m), 818(m), 799(w), 756(sh), 750(m), 743(sh),
720(sh), 696(s), 673(w), 528(s), 515(m), 495(m), 439(w).
1H NMR (400 MHz, DMSO-d6, ppm): d = 9.00 (d, 1H, 8.8 Hz),
8.15 (t, 2H, 7.6 Hz), 7.87–7.82 (m, 2H), 7.73 (t, 1H, 7.6 Hz), 7.42
(ddd, 6H, 10.9, 8.5, 5.2 Hz), 7.22 (dd, 9H, 4.5, 2.5 Hz), 7.17 (d, 2H,
8.2 Hz), 7.07 (d, 2H, 8.4 Hz), 2.26 (s, 3H).
The gas phase geometries of 1, 3, 5 and 7 were optimized with-
out any symmetry restrictions in singlet ground-states with the
DFT method using the hybrid PBE1PBE functional of GAUSSIAN-03
program package [17]. The calculations were performed using
ECP LANL2DZ basis set with an additional d and f function with
the exponent
a = 0.3811 and a = 2.033 for rhenium and the stan-
dard 6-31G basis set for other atoms. For chlorine, oxygen, nitrogen
and phosphorous atoms, diffuse and polarization functions
were added [18]. The optimized geometries of trans-(Cl,Cl)-[Re(p-
13C NMR (125 MHz, DMSO-d6): d = 166.5, 152.8, 150.6, 148.9,
146.1, 143.4, 142.0, 141.4, 141.3, 140.3, 138.8, 137.6, 136.8,
136.2, 135.9, 133.9, 133.8, 133.6, 132.3, 131.5, 131.0, 129.8,
129.5, 129.0, 128.9, 128.8, 127.9, 127.4, 127.4, 126.7, 126.0,
124.8, 122.3, 120.9, 120.0, 22.25 ppm.
NC6H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)],
cis-(Cl,Cl)-[Re(p-NC6
H4CH3)Cl2(4-MeO-quin-2-COO)(PPh3)], trans-(Cl,Cl)-[Re(p-NC6H4
CH3)Cl2(isoquin-1-COO)(PPh3)] and cis-(Cl,Cl)-[Re(p-NC6H4CH3)
Cl2(isoquin-1-COO)(PPh3)] were verified by performing frequency
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

12
I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
(f) P. Leeladee, G.N.L. Jameson, M.A. Siegler, D. Kumar, S.P. de Visser, D.P.
Goldberg, Inorg. Chem. 52 (2013) 4668.
[2] (a) A.K.M. Long, R.P. Yu, G.H. Timmer, J.F. Berry, J. Am. Chem. Soc. 132 (2010)
12228;
calculation. The absence of imaginary frequency in the calculated
vibrational frequencies ensures that the optimized geometries cor-
respond to true energy minima. For the geometry optimizations
the initial X-ray structures were used, and all the subsequent cal-
culations were performed based on optimized geometries.
Natural bond orbital (NBO) calculations were performed with
the NBO code included in Gaussian03 [19].
(b) W.-L. Man, W.W.Y. Lam, S.-M. Yiu, T.-C. Lau, S.-M. Peng, J. Am. Chem. Soc.
126 (2004) 15336;
(c) S. Abbina, S. Bian, C. Oian, G. Du, ACS Catal. 3 (2013) 678;
(d) W.-L. Man, W.W.Y. Lam, T.-C. Lau, Acc. Chem. Res. 47 (2014) 427;
(e) J. Wang, L. Huang, X. Yang, H. Wei, Organometallics 34 (2015) 212.
[3] (a) W.A. Herrmann, R.W. Fischer, J.D.G. Correia, J. Mol. Catal. 94 (1994) 213;
(b) E.A. Ison, E.R. Trivedi, R.A. Corbin, M.M. Abu-Omar, J. Am. Chem. Soc. 127
(2005) 15374;
4.7. Catalytic oxidations
(c) G. Du, P.E. Fanwick, M.M. Abu-Omar, J. Am. Chem. Soc. 129 (2007) 5180;
(d) K.R. Jain, W.A. Herrmann, F.E. Kühn, Coord. Chem. Rev. 252 (2008) 556;
(e) M. Crucianelli, R. Saladino, F. De Angelis, ChemSusChem 3 (2010) 524;
(f) M.-J. Cheng, Dalton Trans. 41 (2012) 3758;
The reactions of alcohols and hydrocarbons were usually car-
ried out in air in thermostated Pyrex cylindrical vessels with vigor-
ous stirring and using MeCN as solvent. Typically, catalyst and the
co-catalyst (acid) were introduced into the reaction mixture in the
form of stock solutions in acetonitrile. The substrate (alcohol or
hydrocarbon) was then added and the reaction started when TBHP
was introduced in one portion. (CAUTION. The combination of air
or molecular oxygen and peroxides with organic compounds at
elevated temperatures may be explosive!). The reactions with 1-
phenylethanol were analyzed by 1H NMR method (solutions in ace-
tone-d6; ‘‘Bruker AMX-400” instrument, 400 MHz). Areas of methyl
group signals were measured to quantify oxygenates formed in
oxidations of 1-phenylethanol. Previously in our works the sam-
ples obtained in the alkane oxidation were typically analyzed twice
(before and after their treatment with PPh3) by GC (LKhM-80-6
instrument, columns 2 m with 5% Carbowax 1500 on 0.25–
0.315 mm Inerton AW-HMDS; carrier gas argon). This method
(an excess of solid triphenylphosphine is added to the samples
10–15 min before the GC analysis) was proposed by one of us ear-
lier [20]. In order to precisely determine concentrations of isomeric
alkanols the samples of reaction solutions after addition of nitro-
methane were analyzed only after reduction with PPh3. Attribution
of peaks was made by comparison with chromatograms of authen-
tic samples.
(g) E.C.B.A. Alegria, L.M.D.R.S. Martins, M.V. Kirillova, A.J.L. Pombeiro, Appl. Cat.
A: General 443–444 (2012) 27–32;
(h) L.M.D.R.S. Martins, E.C.B.A. Alegria, P. Smolenski, M.L. Kuznetsov, Inorg.
´
Chem. 52 (2013) 4534.
[4] (a) U. Schuchardt, D. Mandelli, G.B. Shul’pin, Tetrahedron Lett. 37 (1996) 6487;
(b) G. Bianchini, M. Crucianelli, F. De Angelis, V. Neri, R. Saladino, Tetrahedron
Lett. 45 (2004) 2351;
(c) G. Bianchini, M. Crucianelli, F. De Angelis, V. Neri, R. Saladino, Tetrahedron
Lett. 46 (2005) 2427;
(d) A.M. Kirillov, M. Haukka, M.F.C. Guedes da Silva, A.J.L. Pombeiro, Eur. J.
Inorg. Chem. (2005) 2071;
(e) E.C.B. Alegria, M.V. Kirillova, L.M.D.R.S. Martins, A.J.L. Pombeiro, Appl. Catal.
A: Gen. 317 (2007) 43;
(f) M.L. Kuznetsov, A.J.L. Pombeiro, Inorg. Chem. 48 (2009) 307;
(g) E.A. Karlsson, T. Privalov, Chem. Eur. J. 15 (2009) 1862;
(h) M. Carril, P. Altmann, M. Drees, W. Bonrath, T. Netscher, J. Schütz, F.E. Kühn,
J. Catal. 283 (2011) 55;
(i) M. Carril, P. Altmann, W. Bonrath, T. Netscher, J. Schütz, F.E. Kühn, Sci.
Technol. 2 (2012) 722;
(j) T. Hwang, B.R. Goldsmith, B. Peters, S.L. Scott, Inorg. Chem. 52 (2013) 13904;
(k) L.M.D.R.S. Martins, A.J.L. Pombeiro, Coord. Chem. Rev. 265 (2014) 74.
[5] (a) H.H. Nguyen, C.T. Pham, U. Abram, Polyhedron 99 (2015) 216;
(b) X. Schoultz, T.I.A. Gerber, E. Hosten, R. Betz, L. Rhyman, P. Ramasami,
Polyhedron 96 (2015) 6;
(c) S. Banerjee, S. Bhattacharyya, B. Kumar Dirghangi, M. Menon, A.
Chakravorty, Inorg. Chem. 39 (2000) 6;
(d) I. Booysen, T.I.A. Gerber, E. Hosten, P. Mayer, Z.R. Tshentu, J. Coord. Chem.
60 (2007) 1771;
(e) T.I.A. Gerber, D.G. Luzipo, P. Mayer, J. Coord. Chem. 59 (2006) 1515;
(f) R.A. Eikey, M.M. Abu-Omar, Coord. Chem. Rev. 243 (2003) 83.
[6] U. Abram, R. Alberto, J. Braz. Chem. Soc. 17 (2006) 1486.
Acknowledgements
´
[7] (a) B. Machura, M. Wolff, A. Switlicka, I. Gryca, Polyhedron 29 (2010) 2381;
(b) B. Machura, M. Wolff, I. Gryca, Polyhedron 30 (2011) 142;
(c) B. Machura, M. Wolff, I. Gryca, Inorg. Chim. Acta 370 (2011) 7;
(d) B. Machura, I. Gryca, M. Wolff, Polyhedron 31 (2012) 128;
(e) B. Machura, I. Gryca, Polyhedron 53 (2013) 83;
(f) B. Machura, I. Gryca, J.G. Małecki, F. Alonso, Y. Moglie, Dalton Trans. 43
(2014) 2596;
(g) I. Gryca, B. Machura, J.G. Małecki, L.S. Shul’pina, A.J.L. Pombeiro, G.B.
Shul’pin, Dalton Trans. 43 (2014) 5759;
(h) I. Gryca, B. Machura, J.G. Małecki, J. Kusz, L.S. Shul’pina, N.S. Ikonnikov, G.B.
Shul’pin, Dalton Trans. 45 (2016) 334.
The research was supported by the National Research and
Development Center (NCBiR) under Grant ORGANOMET No:
PBS2/A5/40/2014, the Russian Foundation for Basic Research
(grant 16-03-00254) and the ‘‘Science without Borders Program,
Brazil–Russia”, CAPES (grant A017-2013). The GAUSSIAN-09 calcu-
lations were carried out in the Wrocław Centre for Networking and
Supercomputing, WCSS, Wrocław, Poland, http://www.wcss.wroc.
pl.
[8] (a) G.B. Deacon, R.J. Phillips, Coord. Chem. Rev. 33 (1980) 227;
(b) K. Nakamoto, Infrared and Raman Spectra of Inorganic and Coordination
Compounds, fourth ed., Wiley-Interscience, New York, 1986.
[9] (a) R. Rossi, A. Marchi, A. Duatti, L. Magon, U. Casellato, R. Graziani, G.
Polizzotti, Inorg. Chim. Acta 90 (1984) 121;
Appendix A. Supplementary material
(b) V.M. Bereau, S.I. Khan, M.M. Abu-Omar, Inorg. Chem. 40 (2001) 6767.
[10] (a) M.T. Ahmet, B. Coutinho, J.R. Dilworth, J.R. Miller, S.J. Parrott, Y. Zheng,
Polyhedron 15 (1996) 2041;
(b) P. Mayer, E. Hosten, K.C. Potgieter, T.I.A. Gerber, J. Chem. Crystallogr. 40
(2010) 1146.
[11] S.R. Flechter, A.C. Skapski, J. Chem. Soc., Dalton Trans. (1972) 1073.
[12] (a) L. Wei, J. Zubieta, J.W. Babich, Inorg. Chem. 43 (2004) 6445;
(b) G. Bandoli, T.I.A. Gerber, J. Perils, J.G.H. du Preez, Inorg. Chim. Acta 278
(1998) 96;
CCDC 1453422, 1453423, 1453417, 1453420, 1453421,
1453424, 1453418 and 1453419 contains the supplementary crys-
tallographic data for complexes 1–8. These data can be obtained
free of charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/data_request/cif. Supplementary data
associated with this article can be found, in the online version, at
http://dx.doi.org/10.1016/j.ica.2016.04.030.
(c) G. Bandoli, A. Dolmella, T.I.A. Gerber, J. Perils, J.G.H. du Preez, Bull. Chem.
Soc. Ethiop. 16 (2002) 149;
(d) B. Machura, R. Kruszynski, M. Jaworska, Polyhedron 24 (2005) 1454.
[13] (a) M.V. Kirillova, A.M. Kirillov, D. Mandelli, W.A. Carvalho, A.J.L. Pombeiro, G.
B. Shul’pin, J. Catal. 272 (2010) 9;
References
[1] (a) S.K.-Y. Leung, W.-M. Tsui, J.-S. Huang, C.-M. Che, J.-L. Liang, N. Zhu, J. Am.
Chem. Soc. 127 (2005) 16629;
(b) A.M. Kirillov, M.V. Kirillova, L.S. Shul’pina, P.J. Figiel, K.R. Gruenwald, M.F.C.
G. da Silva, M. Haukka, A.J.L. Pombeiro, G.B. Shul’pin, J. Mol. Catal. A: Chem.
350 (2011) 26;
(c) M.M. Vinogradov, Y.N. Kozlov, A.N. Bilyachenko, D.S. Nesterov, L.S.
Shul’pina, Y.V. Zubavichus, A.J.L. Pombeiro, M.M. Levitsky, A.I. Yalymov, G.B.
Shul’pin, New J. Chem. 39 (2015) 187;
(b) M. Palucki, N.S. Finney, P.J. Pospisil, M.L. Güller, T. Ishida, E.N. Jacobsen, J.
Am. Chem. Soc. 120 (1998) 948;
(c) S.-M. Au, J.-S. Huang, W.-Y. Yu, W.-H. Fung, C.-M. Che, J. Am. Chem. Soc. 121
(1999) 9120;
(d) R.E. Cowley, N.A. Eckert, S. Vaddadi, T.M. Figg, T.R. Cundari, P.L. Holland, J.
Am. Chem. Soc. 133 (2011) 9796;
(e) C. Besson, J.-H. Mirebeau, S. Renaudineau, S. Roland, S. Blanchard, H. Vezin,
C. Courillon, A. Proust, Inorg. Chem. 50 (2011) 2501;
(d) V.B. Romakh, B. Therrien, G. Süss-Fink, G.B. Shul’pin, Inorg. Chem. 46 (2007)
1315.
[14] J. Chatt, J.D. Garforth, N.P. Johnson, G.A. Rowe, J. Chem. Soc. (1964) 1012.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030

I. Gryca et al. / Inorganica Chimica Acta xxx (2016) xxx–xxx
[15] CRYSALIS RED, Version 1.171.33.46, Oxford Diffraction Ltd., 2003. (1997) 119;
13
[16] G.M. Sheldrick, Acta Crystallogr., Sect. A A64 (2008) 112.
(c) P.M.W. Gill, B.G. Johnson, J.A. Pople, M.J. Frisch, Chem. Phys. Lett. 197
(1992) 499.
[17] M.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman,
G. Scalmani, V. Barone, B. Mennucci, G.A. Petersson, H. Nakatsuji, M. Caricato,
X. Li, H.P. Hratchian, A.F. Izmaylov, J. Bloino, G. Zheng, J.L. Sonnenberg, M.
Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y.
Honda, O. Kitao, H. Nakai, T. Vreven, J.A. Montgomery Jr., J.E. Peralta, F. Ogliaro,
M. Bearpark, J.J. Heyd, E. Brothers, K.N. Kudin, V.N. Staroverov, R. Kobayashi, J.
Normand, K. Raghavachari, A. Rendell, J.C. Burant, S.S. Iyengar, J. Tomasi, M.
Cossi, N. Rega, J.M. Millam, M. Klene, J.E. Knox, J.B. Cross, V. Bakken, C. Adamo,
J. Jaramillo, R. Gomperts, R.E. Stratmann, O. Yazyev, A.J. Austin, R. Cammi, C.
Pomelli, J.W. Ochterski, R.L. Martin, K. Morokuma, V.G. Zakrzewski, G.A. Voth,
P. Salvador, J.J. Dannenberg, S. Dapprich, A.D. Daniels, O. Farkas, J.B. Foresman,
J.V. Ortiz, J. Cioslowski, D.J. Fox, Gaussian 09, Revision A.1, Gaussian Inc.,
Wallingford CT, 2009.
[19] (a) NBO Version 3.1, E. D. Glendening, A. E. Reed, J. E. Carpenter, F. Weinhold.;
(b) E. Reed, L.A. Curtiss, F. Weinhold, Chem. Rev. 88 (1988) 899.
[20] (a) G.B. Shul’pin, A.N. Druzhinina, React. Kinet. Catal. Lett. 47 (1992) 207;
(b) G.B. Shul’pin, G.V. Nizova, React. Kinet. Catal. Lett. 48 (1992) 333;
(c) G.B. Shul’pin, J. Mol. Catal. A: Chem. 189 (2002) 39;
(d) G.B. Shul’pin, C. R. Chim. 6 (2003) 163;
(e) G.B. Shul’pin, Mini-Rev. Org. Chem. 6 (2009) 95;
(f) G.B. Shul’pin, Y.N. Kozlov, L.S. Shul’pina, A.R. Kudinov, D. Mandelli, Inorg.
Chem. 48 (2009) 10480;
(g) G.B. Shul’pin, Org. Biomol. Chem. 8 (2010) 4217;
(h) G.B. Shul’pin, Y.N. Kozlov, L.S. Shul’pina, P.V. Petrovskiy, Appl. Organometal.
Chem. 24 (2010) 464;
[18] (a) P.J. Hay, W.R. Wadt, J. Chem. Phys. 82 (1985) 299;
(i) G.B. Shul’pin, Dalton Trans. 42 (2013) 12794;
(b) K. Eichkorn, F. Weigend, O. Treutler, R. Ahlrichs, Theor. Chem. Acc. 97
(j) G.B. Shul’pin, Catalysts 6 (2016) paper No. 50.
Please cite this article in press as: I. Gryca et al., Inorg. Chim. Acta (2016), http://dx.doi.org/10.1016/j.ica.2016.04.030