Cross-coupling reactions in water using ionic liquid-based palladium(II)-phosphinite complexes as outstanding catalysts

Article abstract of DOI:10.1002/aoc.3205

Two new phosphinite ligands based on ionic liquids [(Ph₂PO)C₇H₁₄N₂Cl]Cl (1) and [(Cy₂PO)C₇H₁₄N₂Cl]Cl (2) were synthesized by reaction of 1-(3-chloro-2-hydoxypropyl)-3-methylimidazolium chloride, [C₇H₁₅N₂OCl]Cl, with one equivalent of chlorodiphenylphosphine or chlorodicyclohexylphosphine, respectively, in anhydrous CH₂Cl₂ and under argon atmosphere. The reactions of 1 and 2 with MCl₂(cod) (M=Pd, Pt; cod = 1,5-cyclooctadiene) yield complexes cis-[M([(Ph₂PO)C₇H₁₄N₂Cl]Cl)₂Cl₂] and cis-[M(Cy₂PO) C₇H₁₄N₂Cl]Cl)₂Cl₂], respectively. All complexes were isolated as analytically pure substances and characterized using multinuclear. NMR and infrared spectroscopies and elemental analysis. The catalytic activity of palladium complexes based on ionic liquid phosphinite ligands 1 and 2 was investigated in Suzuki cross-coupling. They show outstanding catalytic activity in coupling of a series of aryl bromides or aryl iodides with phenylboronic acid under the optimized reaction conditions in water. The complexes provide turnover frequencies of 57 600 and 232 800 h^-1 in Suzuki coupling reactions of phenylboronic acid with p-bromoacetophenone or p-iodoacetophenone, respectively, which are the highest values ever reported among similar complexes for Suzuki coupling reactions in water as sole solvent in homogeneous catalysis. Furthermore, the palladium complexes were also found to be highly active catalysts in the Heck reaction affording trans-stilbenes.

Full text of DOI:10.1002/aoc.3205

Full Paper
Received: 15 July 2014
Revised: 15 August 2014
Accepted: 15 August 2014
Published online in Wiley Online Library
(wileyonlinelibrary.com) DOI 10.1002/aoc.3205
Cross-coupling reactions in water using ionic
liquid-based palladium(II)–phosphinite
complexes as outstanding catalysts
Nermin Meriça,b, Murat Aydemira,b*, Uğur Işika, Yusuf Selim Ocakb,c,
Khadichakhan Rafikovad, Salih Paşae, Cezmi Kayana, Feyyaz Durapa,b,
Alexey Zazybind and Hamdi Temelb,f
Two new phosphinite ligands based on ionic liquids [(Ph2PO)C7H14N2Cl]Cl (1) and [(Cy2PO)C7H14N2Cl]Cl (2) were synthesized by
reaction of 1-(3-chloro-2-hydoxypropyl)-3-methylimidazolium chloride, [C7H15N2OCl]Cl, with one equivalent of chlorodiphenyl-
phosphine or chlorodicyclohexylphosphine, respectively, in anhydrous CH2Cl2 and under argon atmosphere. The reactions of 1
and 2 with MCl2(cod) (M= Pd, Pt; cod =1,5-cyclooctadiene) yield complexes cis-[M([(Ph2PO)C7H14N2Cl]Cl)2Cl2] and cis-[M(Cy2PO)
C7H14N2Cl]Cl)2Cl2], respectively. All complexes were isolated as analytically pure substances and characterized using multi-
nuclear NMR and infrared spectroscopies and elemental analysis. The catalytic activity of palladium complexes based on ionic
liquid phosphinite ligands 1 and 2 was investigated in Suzuki cross-coupling. They show outstanding catalytic activity in coupling
of a series of aryl bromides or aryl iodides with phenylboronic acid under the optimized reaction conditions in water. The
complexes provide turnover frequencies of 57 600 and 232 800 hÀ1 in Suzuki coupling reactions of phenylboronic acid with
p-bromoacetophenone or p-iodoacetophenone, respectively, which are the highest values ever reported among similar
complexes for Suzuki coupling reactions in water as sole solvent in homogeneous catalysis. Furthermore, the palladium
complexes were also found to be highly active catalysts in the Heck reaction affording trans-stilbenes. Copyright © 2014 John
Wiley & Sons, Ltd.
Additional supporting information may be found in the online version of this article at the publisher’s web-site.
Keywords: ionic liquid; phosphinite; Suzuki coupling; Heck reaction; palladium; platinum
Suzuki–Miyaura cross-coupling reactions in the sole solvent of
water is a highly attractive aim.
Introduction
Palladium complexes have become the most popular organometal-
lics used in organic synthesis due to their remarkable catalytic po-
tential and their great versatility.[1,2] Especially, palladium catalysts
have been used in most of the carbon–carbon bond formation
reactions such as the Heck and Suzuki reactions[3,4] which are
powerful tools for the preparation of unsymmetric biaryl[5,6] and
stilbene compounds[7] and have been widely employed in the syn-
thesis of pharmaceuticals, herbicides, natural products and ad-
vanced materials.[8–10] Most palladium-catalysed Suzuki coupling
reactions are performed in organic solvents. However, the use of
an environmentally friendly reaction medium, minimization of reac-
tion steps, higher yields and faster reaction remain challenges in
the context of green chemistry for the Suzuki coupling reaction.[11]
In this regard, the use of water, the most abundant and non-toxic
solvent for organic reactions, is becoming more important due to
increasing environmental, economic and safety concerns.[12–14] So
far, a variety of catalytic systems have been reported for the Suzuki
coupling reaction in water, in spite of which they may be less
efficient than in a suitable organic solvent.[15–17] Palladium
catalysts with phosphine ligands,[18] carbene ligands,[19]
palladacycle[20] and other coordinate ligands[21,22] have shown
high activity in Suzuki coupling reactions in water. However,
the development of easily available or readily prepared and in-
expensive palladium catalysts with outstanding activity towards
Metal-containing ionic liquids are considered as promising new
materials that combine the properties of ionic liquids with addi-
tional intrinsic magnetic, spectroscopic or catalytic properties, de-
pending on the incorporated metal ion.[23] Ionic liquids that
contain palladium, ruthenium, platinum, gold and aluminium
*
Correspondence to: Murat Aydemir, Department of Chemistry, Faculty of Science,
University of Dicle, 21280 Diyarbakir, Turkey. E-mail: aydemir@dicle.edu.tr
a Department of Chemistry, Faculty of Science, University of Dicle, 21280 Diyarbakir,
Turkey
b Science and Technology Application and Research Center (DUBTAM), Dicle
University, 21280 Diyarbakir, Turkey
c
Department of Science, Faculty of Education, University of Dicle, 21280 Diyarbakir,
Turkey
d Department of Chemical Engineering, Kazakh-British Technical University, 050000
Almaty, Kazakhstan
e Department of Chemistry, Faculty of Education, University of Dicle, 21280
Diyarbakir, Turkey
f
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Dicle University,
21280 Diyarbakir, Turkey
Appl. Organometal. Chem. (2014)
Copyright © 2014 John Wiley & Sons, Ltd.

N. Meriç et al.
(alsoiron, nickel, zinc or copper) have been used successfully in
catalysis.[24,25] Several metal (Pd, Ru, Rh, V) complex catalysts with
imidazolium tags also have been used in chemical transformations
such as hydrogenation, ring-closing olefin metathesis, and Heck
and Suzuki cross-coupling reactions.[26–29]
Extending our study to develop useful and very effective cata-
lysts, in the present article we describe the synthesis of the ionic liq-
uid compound 1-(3-chloro-2-hydoxypropyl)-3-methylimidazolium
chloride and its corresponding phosphinite ligands with
palladium(II) and platinum(II) metals. We also investigated the
catalytic activities of palladium complexes in the Suzuki and
Heck cross-coupling reactions. Furthermore, the structures of
all new compounds were elucidated using a combination of
multinuclear NMR spectroscopy, infrared spectroscopy and
elemental analysis.
were added to a Schlenk tube under argon atmosphere or in air
and the reaction was followed at various conditions and parame-
ters (temperature, time, base, etc.). After completion of the reaction,
the mixture was cooled, extracted with ethyl acetate–hexane (1:5),
filtered through a pad of silica gel with copious washing, concen-
trated and purified using flash chromatography on silica gel. The
purity of the compounds was checked immediately using GC and
1H NMR. Yields are based on aryl halides.
General Procedure for Heck Coupling Reaction
Palladium complexes based on the ionic liquid phosphinite ligands
(1a and 2a, 0.01 mmol), aryl bromide/chloride/iodide (1.0mmol),
styrene (1.5mmol), base (2mmol) and solvent (3ml) were added
to a Schlenk tube under argon atmosphere or in air and the reac-
tion was monitored at various conditions and parameters (temper-
ature, time, base, etc.). After completion of the reaction, the mixture
was cooled, extracted with ethyl acetate–hexane (1:5), filtered
through a pad of silica gel with copious washing, concentrated
and purified using flash chromatography on silica gel. The purity
of the compounds was checked immediately using GC and 1H
NMR. Yields are based on aryl halides.
Experimental
General
Unless otherwise stated, all reactions were carried out under an at-
mosphere of argon using conventional Schlenk glassware. Solvents
were dried using established procedures and distilled under argon
immediately prior to use. Analytical grade and deuterated solvents
were purchased from Merck. PPh2Cl, PCy2Cl, epichlorohydrin and
1-methylimidazole were purchased from Fluka and were used as
received. The starting materials [MCl2(cod)] (M=Pd, Pt; cod = 1,5-
cyclooctadiene) were prepared according to literature proce-
dures.[30,31] Fourier transform infrared (IR) spectra were recorded
using attenuated total reflection apparatus with a PerkinElmer
Spectrum 100 Fourier transform spectrophotometer. 1H NMR
(400.1 MHz), 13C NMR (100.6MHz) and 31P-{1H} NMR (162.0 MHz)
spectra were recorded using a Bruker AV400 spectrometer, with δ
referenced to external tetramethylsilane and 85% H3PO4, respec-
tively. Elemental analysis of carbon, hydrogen and nitrogen was
carried out with a Costech Combustion System CHNS-O instrument.
Melting points were determined using a Gallenkamp Model appa-
ratus with open capillaries.
Synthesis and Characterization of Ligands and Their
Complexes
General procedure for the synthesis of phosphinites (1 and 2)
A dry and degassed CH2Cl2 (20ml) solution of 1-(3-chloro-2-
hydroxypropyl)-3-methylimidazolium chloride under argon atmo-
sphere (0.100 g, 0.467 mmol) was cooled to À78 °C in an acetone
and dry ice bath. To the cooled solution was added dropwise a hex-
ane solution of n-BuLi (0.293 ml, 0.467 mmol). After the addition,
the mixture was stirred at À78 °C for 1 h and for an additional
30min at room temperature. The reaction solution was cooled to
À78 °C again, and a solution of chlorodiphenylphosphine for 1 or
chlorodicyclohexylphosphine for 2 (0.467 mmol) in CH2Cl2 (10 ml)
was added dropwise to the reaction medium. Stirring was main-
tained for a further 1 h at À78°C. Then the cooling bath was re-
moved and the mixture was stirred for another 1 h at room
temperature. Precipitated lithium chloride was removed by filtra-
tion under argon and then the volatiles were evaporated in vacuo
to leave viscous oily phosphinite ligand 1 or 2.
GC Analyses
GC analyses were performed using a Shimadzu 2010 Plus gas chro-
matograph equipped with a capillary column (5% biphenyl, 95%
dimethylsiloxane; 30 m × 0.32 mm inner diameter×0.25 μm film
thickness). The GC parameters for Suzuki–Miyaura coupling reac-
tions were as follows: initial temperature, 50 °C; initial time, 1 min;
solvent delay, 3.70 min; temperature ramp 1, 10 °CminÀ1; final tem-
perature, 150°C; temperature ramp 2, 15 °CminÀ1; final tempera-
ture, 250 °C; final time, 20.67 min; injector port temperature,
250 °C; detector temperature, 250°C; injection volume, 2.0μl.
Parameters for Heck coupling reactions were as follows: initial
temperature, 50 °C; initial time, 1 min; solvent delay, 3.53min;
temperature ramp, 13 °CminÀ1; final temperature, 300 °C; final
time, 40.46 min; injector port temperature, 250 °C; detector temper-
ature, 250 °C; injection volume, 2.0μl.
Synthesis of 1-{3-chloro-2-[(diphenylphosphanyl)oxy]propyl}-3-
methylimidazolium chloride [(Ph2PO)C7H14N2Cl]Cl (1). Yield
0.180g, 96.8%. 1H NMR (400.1MHz, CDCl3, δ, ppm): 10.14 (s, 1H, –
(CH3)NCHN–), 7.13–7.78 (m, 12H, P(C6H5)2 + –NCHCHN–), 4.94 (m,
1H, NCH2, (a)), 4.71 (br, 1H, –CHOP), 4.57 (m, 1H, NCH2, (b)), 3.91
(m, 1H, –CH2Cl, (a)), 3.85 (m, 1H, –CH2Cl, (b)), 3.80 (s, 3H, NCH3).
13C NMR (100.6MHz, CDCl3, δ, ppm): 36.55 (NCH3), 45.14 (–CH2Cl),
52.52 (NCH2), 78.45 (d, 2 J = 23.1 Hz, (–CHOP), 122.59, 122.90
3
(–NCHCHN–), 129.53 (d, J31P–13C = 10.1 Hz, m-P(C6H5)2), 131.41
2
(p-P(C6H5)2), 135.26 (d, J31P–13C = 19.6 Hz, o-P(C6H5)2), 140.65
1
(d, J31P–13C = 47.8 Hz, i-P(C6H5)2), 138.17 (–(CH3)NCHN–); the as-
1
1
signment was based on the H–13C HETCOR, DEPT and H–1H
COSY spectra. 31P-{1H} NMR (162.0 MHz, CDCl3, δ, ppm): 118.46
(s, OPPh2). IR (ν, cmÀ1): 3053 (aromatic C–H), 1434 (P–Ph), 1060
(O–P). Anal. Calcd for C19H24N2OCl2P (398.29 g molÀ1) (%): C,
57.30; H, 6.07; N, 7.03. Found (%): C, 57.18; H, 6.00; N, 6.96.
Synthesis 1-{3-chloro-2-[(dicyclohexylphosphanyl)oxy]propyl}-3-
methylimidazolium chloride [(Cy2PO)-C7H14N2Cl]Cl (2). Yield
0.183g, 95.5%. 1H NMR (400.1MHz, CDCl3, δ, ppm): 10.48 (s, 1H, –
(CH3)NCHN–), 7.64, 7.45 (2× s, 2H, –NCHCHN–), 4.84 (m, 1H, NCH2,
General Procedure for Suzuki–Miyaura Cross-Coupling
Reaction
Palladium complexes based on the ionic liquid phosphinite ligands
(1a and 2a, 0.001 mmol), aryl bromide/chloride/iodide (1.0mmol),
phenylboronic acid (1.5 mmol), base (2mmol) and solvent (3ml)
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Copyright © 2014 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. (2014)

Coupling reactions in water using Pd-complexes as outstanding catalyst
Pt(II) complex 1b
(a)), 4.53 (m, 1H, NCH2, (b)), 4.16 (br, 1H, –CHOP), 4.10 (s, 3H, NCH3),
3.83 (m, 1H, –CH2Cl, (a)), 3.68 (m, 1H, –CH2Cl, (b)), 1.00–1.95 (m, 22H,
protons of P(C6H11)2). 13C NMR (100.6 MHz, CDCl3, δ, ppm): 26.20,
26.27, 26.64, 26.85, 26.98, 27.21 (CH2 of P(C6H11)2), 37.20 (d,
1 J = 15.1 Hz, CH of P(C6H11)2), 36.77 (NCH3), 44.05 (–CH2Cl), 52.34
(NCH2), 77.32 (d, 2 J = 22.7 Hz, –CHOP), 123.05, 123.43 (–NCHCHN–),
[Pt(cod)Cl2] (0.047 g, 0.126 mmol) and 1 (0.100 g, 0.251 mmol) were
dissolved in dry CH2Cl2 (25 ml) under argon atmosphere and stirred
overnight at room temperature. The volume was concentrated to
ca 1–2 ml under reduced pressure, and addition of petroleum ether
(20 ml) gave the corresponding Pt(II) complex as a white solid. The
product was collected by filtration and dried in vacuo. Yield 0.104 g,
1
138.67 (–(CH3)NCHN–); the assignment was based on the H–13C
HETCOR, DEPT and 1H–1H COSY spectra. 31P-{1H} NMR (162.0 MHz,
CDCl3, δ, ppm): 148.76 (s, OPCy2). IR (ν, cmÀ1): 2923, 2850 (aliphatic
C–H), 1446 (P–Cy), 1059 (O–P). Anal. Calcd for C19H36N2OCl2P
(410.39 g molÀ1) (%): C, 55.61; H, 8.84; N, 6.83. Found (%): C, 55.56;
H, 8.71; N, 6.70.
1
78.2%; m.p. 197–209 °C. H NMR (400.1MHz, CDCl3, δ, ppm): 9.15
(s, 2H, –(CH3)NCHN–), 7.42–8.07 (m, 20H, P(C6H5)2), 7.02 (d, 2H,
J = 1.7Hz, –NCHCHN–), 6.98 (d, 2H, J = 1.7Hz, –NCHCHN–), 5.62 (m,
2H, NCH2, (a)), 4.25 (m, 2H, NCH2, (b)), 3.97 (s, 6H, NCH3), 3.95 (br,
2H, –CHOP), 3.51 (m, 2H, –CH2Cl, (a)), 3.37 (m, 2H, –CH2Cl, (b)). 13
C
NMR (100.6 MHz, CDCl3, δ, ppm): 36.07 (NCH3), 43.02 (–CH2Cl),
47.18 (NCH2), 73.06 (d, 2 J = 21.8 Hz, –CHOP), 120.80, 123.49
Synthesis of Metal (Pd(II), Pt(II)) Complexes
3
(–NCHCHN–), 128.66 (s, p-P(C6H5)2), 131.68 (d, J31P–13C = 10.1 Hz,
2
m-P(C6H5)2), 134.41 (d, J31P–13C = 13.2 Hz, o-P(C6H5)2), 137.56
Pd(II) complex 1a
1
((CH3)NCHN–), 141.75 (d, J31P–13C = 44.2 Hz, i-P(C6H5)2); assignment
was based on the H–13C HETCOR, DEPT and H–1H COSY spectra.
31P-{1H} NMR (162.0 MHz, CDCl3, δ, ppm): 77.12 (s, J(PPt) = 4273.6 Hz,
Pt–OPPh2). IR (ν, cmÀ1): 3053 (aromatic C–H), 1436 (P–Ph), 1045
(O–P), 303, 283 (Pt–Cl). Anal. Calcd for C38H48N4O2P2PtCl6 (1062.57 g
molÀ1) (%): C, 42.95; H, 4.55; N, 5.27. Found (%): C, 42.88; H, 4.49; N, 5.21.
[Pd(cod)Cl2] (0.036 g, 0.126mmol) and 1 (0.100g, 0.251 mmol) were
dissolved in dry CH2Cl2 (25 ml) under argon atmosphere and stirred
for 15 min at room temperature. The volume was concentrated to
ca 1–2 ml under reduced pressure, and addition of petroleum ether
(20 ml) gave the corresponding Pd(II) complex as a clear yellow
solid. The product was collected by filtration and dried in vacuo.
Yield 0.095 g, 77.7%; m.p. 143–145 °C. 1H NMR (400.1 MHz,
DMSO-d6, δ, ppm): 9.23 (s, 2H, –(CH3)NCHN–), 7.42–7.78 (m, 24H, P
(C6H5)2 + –NCHCHN–), 5.98 (br, 2H, –CHOP), 4.81 (m, 4H, NCH2),
4.11 (br, 4H, –CH2Cl), 3.77 (s, 6H, NCH3). 13C NMR (100.6 MHz,
DMSO-d6, δ, ppm): 36.44 (NCH3), 45.56 (–CH2Cl), 51.41 (NCH2),
78.13 (d, 2 J = 22.9 Hz, –CHOP), 123.63, 124.13 (–NCHCHN–), 128.28
(m-P(C6H5)2), 131.30, (p-P(C6H5)2), 131.63 (o-P(C6H5)2), 137.60
((CH3)NCHN–), 139.25 (d, 1J31P–13C = 38.2 Hz, i-P(C6H5)2); the assign-
1
1
Pt(II) complex 2b
[Pt(cod)Cl2] (0.046 g, 0.122 mmol) and 2 (0.100 g, 0.244 mmol) were
dissolved in dry CH2Cl2 (25 ml) under argon atmosphere and stirred
overnight at room temperature. The volume was concentrated to
ca 1–2 ml under reduced pressure, and addition of petroleum ether
(20 ml) gave the corresponding Pt(II) complex as a white solid. The
product was collected by filtration and dried in vacuo. Yield 0.102 g,
77.2%; m.p. 99–101 °C. 1H NMR (400.1MHz, CDCl3, δ, ppm): 9.90 (s,
2H, –(CH3)NCHN–), 7.47, 7.43 (2× s, 4H, –NCHCHN–), 5.95 (br, 2H, –
CHOP), 5.16 (m, 2H, NCH2, (a)), 4.62 (m, 2H, NCH2, (b)), 4.10 (s, 6H,
NCH3), 4.25 (m, 2H, –CH2Cl, (a)), 3.95 (m, 2H, –CH2Cl, (b)), 2.71 (m,
4H, CH of P(C6H11)2), 1.26–2.38 (m, 40H, CH2 of P(C6H11)2). 13C
NMR (100.6 MHz, CDCl3, δ, ppm): 26.38, 26.49, 27.13, 27.31, 27.61,
28.38 (CH2 of P(C6H11)2), 37.28 (NCH3), 39.95 (d, 1 J= 35.2 Hz, CH of
P(C6H11)2), 45.60 (–CH2Cl), 52.18 (NCH2), 77.35 (d, 2 J = 21.2 Hz, –
CHOP), 122.85, 123.30 (–NCHCHN–), 137.91 (–(CH3)NCHN–); assign-
1
1
ment was based on the H–13C HETCOR, DEPT and H–1H COSY
spectra. 31P-{1H} NMR (162.0 MHz, DMSO-d6, δ, ppm): 104.59; (CDCl3,
δ, ppm): 107.20 (s, Pd–OPPh2). IR (KBr, ν, cmÀ1): 3053 (aromatic
C–H), 1436 (P–Ph), 1045 (O–P), 301, 281 (Pd–Cl). Anal. Calcd for
C38H48N4O2P2PdCl6 (973.91 g molÀ1) (%): C, 46.87; H, 4.97; N, 5.75.
Found (%): C, 46.79; H, 4.90; N, 5.68.
Pd(II) complex 2a
1
1
ment was based on the H–13C HETCOR, DEPT and H–1H COSY
[Pd(cod)Cl2] (0.035 g, 0.122mmol) and 2 (0.100g, 0.244 mmol) were
dissolved in dry CH2Cl2 (25 ml) under argon atmosphere and stirred
for 15 min at room temperature. The volume was concentrated to
ca 1–2 ml under reduced pressure, and addition of petroleum ether
(20 ml) gave the corresponding Pd(II) complex as a clear yellow
solid. The product was collected by filtration and dried in vacuo.
Yield 0.097 g, 79.8%; m.p. 178–180 °C. 1H NMR (400.1 MHz,
DMSO-d6, δ, ppm): 9.25 (s, 2H, –(CH3)NCHN–), 7.81–7.86 (2× s, 4H,
–NCHCHN–), 5.74 (br, 2H, –CHOP), 4.63 (m, 4H, NCH2), 4.27 (m, 2H,
–CH2Cl, (a)), 4.09 (m, 2H, –CH2Cl, (b)), 3.88 (s, 6H, NCH3), 2.67 (m,
2H, CH of P(C6H11)2 (a)), 2.33 (m, 2H, CH of P(C6H11)2 (b)),
1.15–1.72 (m, 40H, CH2 of P(C6H11)2). 13C NMR (100.6 MHz,
DMSO-d6, δ, ppm): 26.75, 26.90, 27.04, 27.15, 27.38, 27.71 (CH2 of
P(C6H11)2), 36.51 (NCH3), 41.23 (d, 1 J = 33.7 Hz, CH of P(C6H11)2),
45.98 (–CH2Cl), 51.48 (NCH2), 77.94 (d, 2 J = 20.5 Hz, –CHOP),
123.63, 124.04 (–NCHCHN–), 137.74 (–(CH3)NCHN–); assignment
was based on the 1H–13C HETCOR, DEPT and 1H–1H COSY spectra.
31P-{1H} NMR (162.0 MHz, DMSO-d6, δ, ppm): 129.77 (s, Pd–OPCy2);
(CDCl3, δ, ppm): 132.48 (s, Pd–OPCy2). IR (ν, cmÀ1): 2926, 2852 (ali-
phatic C–H), 1436 (P–Cy), 1036 (O–P), 303, 283 (Pd–Cl). Anal. Calcd
for C38H72N4O2P2PdCl6 (998.10 g molÀ1) (%): C, 45.73; H, 7.27; N,
5.61. Found (%): C, 45.67; H, 7.20; N, 5.55.
spectra. 31P-{1H} NMR (162.0MHz, CDCl3, δ, ppm): 97.24 (s, J(PPt)
=
4082.4 Hz, Pt–OPCy2). IR (KBr, ν, cmÀ1): 2926, 2852 (aliphatic C–H),
1436 (P–Cy), 1036 (O–P), 328, 278 (Pt–Cl). Anal. Calcd for
C38H72N4O2P2PtCl6 (1086.76 g molÀ1) (%): C, 42.00; H, 6.68; N, 5.16.
Found (%): C, 41.90; H, 6.58; N, 5.09.
Results and Discussion
Synthesis and Characterization of Ligands and Their Metal
Complexes
The synthesis of 1-(3-chloro-2-hydroxypropyl)-3-methylimidazolium
chloride, [C7H15N2OCl]Cl, was accomplished in one step from the re-
action of 1-methylimidazole and epichlorohydrin in ethanol at room
temperature, according to literature procedures.[32] 1-(3-Chloro-2-
hydroxypropyl)-3-methylimidazolium chloride was characterized
using elemental analysis, IR spectroscopy, TGA–DTA and multinu-
clear NMR spectroscopies and also X-ray analysis (to be published
elsewhere). As shown in Scheme 1, phosphinite ligands 1 and 2
were synthesized[33] from the starting materials PPh2Cl and PCy2Cl,
respectively, in CH2Cl2 solution by the hydrolysis method.[34,22]
Appl. Organometal. Chem. (2014)
Copyright © 2014 John Wiley & Sons, Ltd.
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N. Meriç et al.
to have the cis configuration, characteristic of
phosphinites having mutual cis arrangement.[41–43]
The 13C-{1H} NMR spectra display well-resolved sig-
nals for the phenyls and cyclohexyl carbons,
respectively.[44] Furthermore, the 1H NMR spectral
data of complexes 1a and 2a are consistent
with the proposed structures, and the composi-
tions of the two complexes have been further
confirmed by elemental analysis and IR spec-
troscopy, and found to be in good agreement
with the theoretical data. Other pertinent spec-
troscopic and analytic data are given in the
experimental section.
Based on the above information, we also exam-
ined the coordination chemistry of 1 and 2 with
[Pt(cod)Cl2] precursor. The reaction of [Pt(cod)Cl2]
with two equivalents of 1 or 2 leads to the forma-
tion of complexes 1b and 2b, respectively, in high
yields as the main products. In both complexes,
the phosphinites bind the metal centre as
monodentate ligand. The formation of compounds
1b and 2b was followed by monitoring the 31P-{1H}
NMR spectra, which show single resonances at
Scheme 1. Synthesis of compounds [(Ph2PO)C7H14N2Cl]Cl (1), [(Cy2PO)C7H14N2Cl]Cl (2), [Pd
((Ph2PO)C7H14N2Cl)2Cl2]Cl2 (1a), [Pd((Cy2PO)C7H14N2Cl)2Cl2]Cl2 (2a), [Pt((Ph2PO)C7H14N2Cl)2Cl2]
Cl2 (1b) and [Pt((Cy2PO)C7H14N2Cl)2Cl2]Cl2 (2b). (i) 1 equiv. Ph2PCl or Cy2PCl, 1 equiv. n-BuLi,
CH2Cl2; (ii) 0.5 equiv. [M(cod)Cl2] (M= Pd, Pt), CH2Cl2.
77.12 and 97.24 ppm, respectively, consistent with structures of
the anticipated complexes (supporting information).[45] The com-
plexes 1b and 2b exhibit large JPtP coupling of 4273.6 and
4082.4Hz, respectively, which are characteristic of phosphinites
having mutual cis arrangement (Fig. S2).[46–48] 1H NMR spectral data
of 1b and 2b are consistent with the proposed structures. Further-
more, in the 13C-{1H} NMR spectra of 1b and 2b, J(31P–13C) coupling
constants are measured for the carbons of the phenyl rings and
cyclohexyl moiety, and they are consistent with the literature
values.[49,50] The structural compositions of complexes 1b and 2b
The coordination chemistry of ligands 1 and 2 was studied by
forming their palladium and platinum complexes. Reaction of 1 or
2 with [Pd(cod)Cl2] gives the corresponding Pd(II) complexes 1a
and 2a in high yields (ca 80%). In the 31P-{1H} NMR spectra, each
of 1a and 2a gives one signal at 107.20 and 132.48ppm, respec-
tively, which are within the expected range of other reported struc-
turally similar complexes (Fig. S1).[22,38,39] Typical spectra of these
complexes are illustrated in the supporting information. Both of
the isolated dichloropalladium(II) complexes 1a and 2a are found
1
Table 1. Suzuki coupling reactions of p-acetobromobenzene with phenylboronic acid catalysed by the ionic liquid-based palladium
(II)–phosphinite catalysts 1a and 2a
Entry
Catalyst Time (min)
Solvent
Dioxane
Base Temperature (°C) Atmosphere Conversion (%) Yield (%) TOF (hÀ1
)
1a
30
K2CO3
100
Ar
98
97
1 940
1
2
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
45
30
45
60
180
60
180
1
Dioxane
Dioxane
Dioxane
DMF
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
100
100
100
110
110
110
110
110
110
110
110
25
Ar
99
100
98
98
97
97
99
95
99
96
96
98
96
98
98
98
96
95
96
97
96
97
1 307
1 940
1 293
990
3
Air
Air
Ar
4
5
99
6
DMF
Ar
97
317
7
DMF
Air
Air
Ar
99
990
8
DMF
98
320
9
DMF–H2O (1/4) K2CO3
DMF–H2O (1/4) K2CO3
DMF–H2O (1/4) K2CO3
DMF–H2O (1/4) K2CO3
DMF–H2O (1/4) K2CO3
DMF–H2O (1/4) K2CO3
99
57 600
19 600
57 600
19 600
980
10
11
12
13
14
15
16
17
18
19
20
3
Ar
100
98
1
Air
Air
Air
Air
Ar
3
100
99
60
120
1
25
99
490
H2O
H2O
H2O
H2O
H2O
H2O
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
100
100
100
100
25
98
57 600
19 000
57 600
19 400
960
3
Ar
97
1
Air
Air
Air
Air
98
3
99
60
180
99
25
99
323
Reaction conditions: 1.0mmol of p-CH3C(O)C6H4Br aryl bromide, 1.5mmol of phenylboronic acid, 2.0mmol K2CO3, 0.001mmol
1
catalyst, solvent (3.0ml). Purity of compounds was checked by H NMR and yields are based on aryl bromide. All reactions were
monitored using GC for 1a and 2a. TOF = (mol product/mol catalyst) × hÀ1
.
wileyonlinelibrary.com/journal/aoc
Copyright © 2014 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. (2014)

Coupling reactions in water using Pd-complexes as outstanding catalyst
were further confirmed from IR spectroscopy and microanalysis,
and found to be in good agreement with the theoretical data.
In conclusion, results of the optimization studies demonstrate
obviously that complex 1a including phenyl (Ph) moieties on the
phosphorus atoms is a more active and efficient catalyst leading
to nearly quantitative conversions.
Suzuki–Miyaura and Mizoroki–Heck Coupling Reactions
Encouraged by the activities obtained in these preliminary stud-
ies, optimization studies were also conducted to determine how
bases affect the coupling reaction. As illustrated in Table 2, initial
studies were performed using different bases (Cs2CO3, KOH, NaOH
and KOtBu) together with K2CO3 in order to optimize the reaction
conditions for the coupling of p-bromoacetophenone with
phenylboronic acid in the presence of complexes 1a and 2a
(0.001 mmol Pd catalyst) under aerobic conditions. As evident from
Table 2, the best turnover frequency (TOF) is obtained in the Suzuki
reaction carried out at 100°C, implying that K2CO3 as the base is the
best choice for the cross-coupling reactions and other bases such as
Cs2CO3, KOH, NaOH and KtOBu are slightly less effective. In addi-
tion, the effect of base-to-substrate mole ratio on the coupling reac-
tion was also investigated. Using K2CO3 at a base-to-substrate mole
ratio of 2:1 affords the highest TOF value, while the TOF value is
lower at a mole ratio of 1:1. However, increasing the base-to-
substrate mole ratio does not increase the conversion rate (Table 2,
entries 11–13). The reproducibility of each catalytic reaction was
confirmed by carrying out the catalytic reaction at least three times.
With the best conditions at hand, we also carried out further ex-
periments to investigate the scope of Suzuki cross-coupling using
catalysts 1a and 2a with various substrates, including aryl bromides,
chlorides and iodides having electron-withdrawing or electron-
donating substituents (Table 3, entries 1–12). Aryl iodides react with
phenylboronic acid in a markedly short time of approximately 15 s
and the yields of the corresponding products are very satisfactory
(Table 3, entries 1–4). Encouraged by these results, we studied the
reactivity between substituted aryl bromides and phenylboronic
In a pilot study to investigate the catalytic activity of palladium
complexes based on ionic liquid phosphinite ligands, we initially
tested the Suzuki cross-coupling reaction between aryl bromides
and boronic acid.[51] The control experiments show that the
coupling reaction does not occur in the absence of the catalyst.
The reaction parameters for the Suzuki cross-coupling reaction
were optimized through a series of experiments. The influences of
temperature, base, solvent and atmosphere were systematically
studied using the coupling of p-bromoacetobenzene and
phenylboronic acid as probe reaction. Furthermore, a change of
the reaction atmosphere from an inert gas to ambient atmosphere
has no negative influence on the activity of the catalysts (Table 1,
entries 3, 4, 7, 8, 11, 12, 17, 18). Therefore, the coupling reactions
were performed in air. Optimization studies were conducted to de-
termine how solvent and temperature affect the coupling reaction.
As demonstrated in Table 1, the best catalytic activities are not ob-
tained until the Suzuki reaction is carried out at 100 °C in aqueous
medium and DMF–H2O (1:4) (Table 1, entries 9–20). We also find
that, under identical conditions, the coupled product is obtained
in higher yield at elevated temperature and the reaction occurs at
room temperature (Table 1, entries 13, 14, 19 and 20). From Table 1,
it can be seen that the efficiency of complexes is different from
each other. For example, the Suzuki reaction with catalyst 1a always
shows higher catalytic activity than that with catalyst 2a. One
can also see from Table 1 that for a typical reaction of
p-bromoacetobenzene and phenylboronic acid, the reaction rate
is dependent on the alkyl substituents on the phosphorus atom.
Table 2. Suzuki coupling reactions of p-acetobromobenzene with phenylboronic acid catalysed by the palladium(II)–
phosphinite catalysts 1a and 2a based on ionic liquid
Entry Catalyst Time (min) Solvent Base Temperature (°C) Atmosphere Conversion (%) Yield (%) TOF (hÀ1
)
1a
1
H2O
Cs2CO3
100
Air
95
92
55 200
1
2
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
1a
1a
3
1
3
3
8
2
5
2
5
1
1
1
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
Cs2CO3
K2CO3
K2CO3
NaOH
NaOH
KOH
100
100
100
100
100
100
100
100
100
100
100
100
Air
Air
Air
Air
Air
Air
Air
Air
Air
Air
Air
Air
96
98
99
98
99
99
97
98
99
85
98
76
92
96
97
97
98
97
95
95
96
81
96
72
18 400
57 600
19 400
19 400
7 350
3
4
5
6
7
29 100
11 400
28 500
11 520
48 600
57 600
43 200
8
KOH
9
KtOBu
KtOBu
K2CO3
K2CO3
K2CO3
10
11a
12b
13c
Reaction conditions: 1.0 mmol of aryl bromide, 1.5 mmol of phenylboronic acid, 2.0 mmol base, 0.001 mmol catalyst, water
(3.0 ml). Purity of compounds was checked by 1H NMR and yields are based on aryl bromide. All reactions were monitored
using GC for 1a and 2a. TOF = (mol product/mol catalyst) × hÀ1
.
aBase-to-substrate mole ratio= 1:1.
bBase-to-substrate mole ratio = 2:1.
cBase-to-substrate mole ratio = 5:1.
Appl. Organometal. Chem. (2014)
Copyright © 2014 John Wiley & Sons, Ltd.
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N. Meriç et al.
Table 3. Suzuki coupling reactions of aryl halides with phenylboronic acid catalysed by palladium(II)–phosphinite catalysts 1a and 2a
based on ionic liquid
Entry
X
R
Catalyst
Time (min)
0.25
Conversion (%)
98
Yield (%)
96
TOF (hÀ1
230 400
)
I
H
H
1a
1
2
I
2a
1a
2a
1a
2a
1a
2a
1a
2a
1a
2a
0.75
0.25
0.75
0.5
2
97
99
95
97
97
96
92
97
96
96
96
99
97
76 000
232 800
77 600
115 200
27 600
29 100
11 520
14 400
8 229
3
I
C(O)CH3
C(O)CH3
C(O)H
C(O)H
H
4
I
99
5
Br
Br
Br
Br
Br
Br
Br
Br
98
6
95
7
2
98
8
H
5
97
9
OCH3
OCH3
CH3
4
98
10
11
12
7
100
100
99
5
11 880
6 467
CH3
9
Reaction conditions: 1.0 mmol of p-RC6H4X aryl halogens, 1.5 mmol of phenylboronic acid, 2.0 mmol K2CO3, 0.001 mmol catalyst (1a or 2a),
water (3.0 ml). Purity of compounds was checked by 1H NMR and yields are based on aryl halide. All reactions were monitored using GC;
100 °C. TOF = (mol product/mol catalyst) × hÀ1
.
acid. Compared to aryl iodides, the reaction takes longer (Table 3);
therefore we can easily conclude that the electronic nature of the
aryl bromides has a clear effect on the coupling reactions (Table 3,
entries 5–12). For example, the coupling reaction of electron-rich
4-bromotoluene with phenylboronic acid has a TOF value of 11
880 hÀ1, but for electron-deficient 4-bromobenzaldehyde, the de-
sired coupled product is obtained with a TOF value of 115
200 hÀ1. After obtaining such an outstanding activity in Suzuki cou-
pling reactions of p-iodoacetophenone or iodobenzene with
phenylboronic acid catalysed by complexes 1a and 2a in water,
we studied the catalytic activity of complexes in the Suzuki cou-
pling reactions of aryl chlorides with phenylboronic acid in water.
However, the highest conversion reached is 63% in the presence
of K2CO3 within 30 min in water at 100°C and a longer reaction time
does not give any further conversion. It is well known that chlorides
are generally less reactive towards Suzuki coupling reactions un-
der the same conditions used for the coupling of bromides and
iodides. The low reactivity of chlorides is usually attributed to
the strength of the C–Cl bond (bond dissociation energies (kcal
molÀ1): Ph–Cl, 96; Ph–Br, 81; Ph–I, 65), which leads to aryl
chlorides being reluctant in adding oxidatively to Pd(0) centres,
a critical initial step in Pd-catalysed coupling reactions.[52,53] In
addition, because of the strength of the Pt–C bonds, Pt(II)–phosphinite
systems exhibit no catalytic activity in the Suzuki–Miyaura cross-
coupling reaction.[54]
Encouraged by the outstanding catalytic activities obtained in the
Suzuki–Miyaura cross-coupling reaction, we next extended our
investigations to the Mizoroki–Heck reaction. The results are
Table 4. Heck coupling reactions of p-bromoacetophenone with styrene catalysed by palladium(II)–phosphinite catalysts 1a and 2a
Entry Catalyst Time (h)
Solvent
DMF
Base
Temperature (°C) Atmosphere
Conversion (%) Yield (%)
TOF (hÀ1
49
)
1a
2
K2CO3
120
Ar
98
97
1
2
2a
1a
2a
1a
2a
1a
2a
2
2
2
8
8
8
8
DMF
DMF
DMF
DMF
DMF
DMF
DMF
K2CO3
K2CO3
K2CO3
Cs2CO3
Cs2CO3
Cs2CO3
Cs2CO3
120
120
120
120
120
120
120
Ar
Air
Air
Ar
99
99
98
97
99
99
98
96
97
96
95
96
97
95
48
49
48
12
12
12
12
3
4
5
6
7
8
Ar
Air
Air
Reaction conditions: 1.0mmol of p-CH3C(O)C6H4Br aryl bromide, 1.5mmol of styrene, 2.0mmol base, 0.01mmol catalyst, DMF (3.0ml).
Purity of compounds was checked by 1H NMR and yields are based on aryl bromide. All reactions were monitored using GC for 1a and
2a. TOF = (mol product/mol catalyst) × hÀ1
.
wileyonlinelibrary.com/journal/aoc
Copyright © 2014 John Wiley & Sons, Ltd.
Appl. Organometal. Chem. (2014)

Coupling reactions in water using Pd-complexes as outstanding catalyst
Table 5. Heck coupling reactions of aryl bromides with styrene catalysed by palladium(II)–phosphinite catalysts 1a and 2a
Entry
R
Catalyst
Time (h)
2
Conversion (%)
98
Yield (%)
96
TOF (hÀ1
48
)
C(O)H
1a
1
2
C(O)H
H
2a
1a
2a
1a
2a
1a
2a
2
3
3
6
6
5
5
100
98
92
97
96
96
96
99
97
46
32
32
16
16
20
19
3
4
5
6
7
8
H
97
OCH3
OCH3
CH3
CH3
98
100
100
99
Reaction conditions: 1.0mmol of p-RC6H4Br aryl bromide, 1.5mmol of styrene, 2.0mmol K2CO3, 0.01mmol catalyst (1a or 2a), DMF
1
(3.0ml). Purity of compounds was checked by H NMR and yields are based on aryl bromide. All reactions were monitored using
GC; 120 °C for 1a and 2a. TOF = (mol product/mol catalyst) × hÀ1
.
summarized in Tables 4 and 5. It is well known that among the
different methods used to form carbon–carbon bonds, palladium-
catalysed carbon–carbon bond formation between aryl halides and
olefins has become an excellent tool for the synthesis of elaborate
styrene derivatives.[55,56] Furthermore, the palladium-catalysed
arylation or vinylation of olefins, universally referred to as the Heck
reaction, has received increasing attention in the last decade, as it is
a selective method to form new carbon–carbon bonds in a single
operational step.[57,58] The reaction is appealing because of its
tolerance of nearly any solvent and functional group on the
substrates, its high selectivity and its moderate toxicity.[59,60] It is
Conclusions
This report describes for the first time the preparation and charac-
terization of new Pd(II) and Pt(II) complexes based on ionic liquid
phosphinite ligands and an investigation of their use as
pre-catalysts in the Suzuki coupling and Heck reactions of aryl ha-
lides. Only the palladium complexes were found to show outstand-
ing catalytic activity in the Suzuki coupling reactions of aryl
bromides in aqueous medium. Contrary to expectation, these cata-
lysts are not very active for the Heck reaction. But, among the re-
ported similar palladium catalysts in homogeneous systems, the
Pd(II) complexes based on ionic liquid phosphinite ligands provide
record catalytic activity in the Suzuki–Miyaura coupling reaction of
p-bromoacetophenone with phenylboronic acid. In addition, a
change in the reaction atmosphere from an inert gas to ambient at-
mosphere had no negative influence on the activity of the catalysts.
In both cases, the catalytic activities of these complexes were found
to be higher in reactions of aryl bromides with electron-
withdrawing substituents than with electron-releasing substituents.
The outstanding catalytic activity and facile preparation of these
catalysts raise the prospect of using this type of simply prepared
material for Suzuki–Miyaura cross-coupling reactions in industrial
applications as well as in small-scale organic synthesis.
a
powerful and versatile method for the synthesis of
polyfunctional compounds, e.g. dienes, cinnamic esters and
other variously substituted olefinic compounds, which are pri-
marily applied as dyes and UV absorbers, and as intermediates
for pharmaceuticals, agrochemicals and fragrances.[61,62]
The rate of coupling in the Heck reaction is dependent on a
variety of parameters such as temperature, solvent, base and
catalyst loading. Generally, the Heck reaction requires high
temperatures (higher than 100 °C) and polar solvents. For the
choice of base, we investigated Cs2CO3 and K2CO3 which are
expected to be the best bases for this reaction. Furthermore, a
change in the reaction atmosphere from an inert gas to
ambient atmosphere has no negative influence on the activity of
the catalysts (Table 4, entries 3, 4, 7, 8). Therefore, the
coupling reactions were performed in air. Finally, from the
optimization studies, we see that use of 1.0 mmol%, 2 equiva-
lents of K2CO3 in DMF at 120 °C for 1a and 2a leads to the
best conversions with the highest TOF values. We firstly inves-
tigated the catalytic activities of 1a and 2a for the coupling of
Acknowledgement
Partial support from Dicle University (project number: DÜBAP-07-
01-22 and 12-FF-140) is gratefully acknowledged.
p-bromoacetophenone with styrene (Table 4).
A control
References
experiment indicates that the coupling reaction does not
happen in the absence of 1a or 2a. Under the determined
reaction conditions, a wide range of aryl bromides bearing
electron-donating and electron-withdrawing groups react with
styrene, affording the coupled products in moderate to good
yields. As expected, electron-deficient bromides are beneficial
for the conversions (Table 5). Using aryl chlorides instead of
aryl bromides yields only small amounts of stilbene deriva-
tives under the conditions employed for bromides.
[1] W. Hieringer, Applied Homogeneous Catalysis with Organometallic
Compounds, Wiley-VCH, Weinheim, 1996, pp. 721.
[2] Á. Molnár, Chem. Rev. 2011, 111, 2251.
[3] R. B. Bedford, C. S. J. Cazin, D. Holder, Coord. Chem. Rev. 2004, 248, 2283.
[4] I. P. Beletskaya, A. V. Cheprakov, Chem. Rev. 2000, 100, 3009.
[5] P. Lloyd-Williams, E. Giralt, Chem. Soc. Rev. 2001, 30, 145.
[6] C. Najera, J. Gil-Molto, S. Karlström, L. R. Falvello, Org. Lett. 2003, 5, 1451.
[7] N. Biricik, F. Durap, C. Kayan, B. Gümgüm, N. Gürbüz, İ. Özdemir,
W. H. Ang, Z. Fei, R. Scopelliti, J. Organomet. Chem. 2008, 693, 2693.
Appl. Organometal. Chem. (2014)
Copyright © 2014 John Wiley & Sons, Ltd.
wileyonlinelibrary.com/journal/aoc

N. Meriç et al.
[8] N. Miyaura, in Metal-Catalyzed Cross-Coupling Reactions, 2nd edition
(Eds.: A. de Meijere, F. Diederich), Wiley-VCH, Weinheim, 2004, pp. 41
chap. 2.
[9] D. Astruc, F. Lu, J. R. Aranzaes, Angew. Chem. Int. Ed. 2005, 44, 7852.
[10] W. Han, C. Liu, Z. L. Jin, Org. Lett. 2007, 9, 4005.
[11] K. H. Shaughnessy, R. B. DeVasher, Curr. Org. Chem. 2005, 9, 585.
[12] C. J. Li, Chem. Rev. 2005, 105, 3095.
[13] C. J. Li, L. Chen, Chem. Soc. Rev. 2006, 35, 68.
[14] C. J. Li, L. Chen, Comprehensive Organic Reactions in Aqueous Media,
Wiley, New York, 2007.
[15] P. Zheng, W. Zhang, J. Catal. 2007, 250, 324.
[16] F. Churruca, R. SanMartin, B. Ines, I. Tellitu, E. Dominguez, Adv. Synth.
Catal. 2006, 348, 1836.
[38] E. A. Broger, W. Burkart, M. Hennig, M. Scalone, R. Schmid, Tetrahedron:
Asymmetry 1998, 9, 4043.
[39] E. J. Zijs, J. I. Van der Vlugt, D. M. Tooke, A. L. Spek, D. Vogt, J. Chem. Soc.
Dalton Trans. 2005, 512.
[40] M. R. I. Zuburi, A. M. Z. Slawin, M. Wainwright, J. D. Woollins, Polyhedron
2002, 21, 1729.
[41] A. M. Z. Slawin, J. Wheatley, J. D. Woollins, Eur. J. Inorg. Chem. 2005, 713.
[42] M. R. I. Zuburi, H. L. Milton, A. M. Z. Slawin, J. D. Woollins, Polyhedron
2004, 23, 865.
[43] A. M. Z. Slawin, J. Wheatley, J. D. Woollins, Polyhedron 2004,
23, 2569.
[44] M. R. I. Zuburi, H. L. Milton, D. J. Cole-Hamilton, A. M. Z. Slawin,
J. D. Woollins, Polyhedron 2004, 23, 693.
[45] K. G. Gaw, A. M. Z. Slawin, M. B. Smith, Organometallics 1999, 18, 3255.
[46] M. S. Balakrishna, D. Suresh, P. P. George, J. T. Mague, Polyhedron 2006,
25, 3215.
[47] K. G. Gaw, M. B. Smith, A. M. Z. Slawin, New J. Chem. 2000, 24, 429.
[48] A. M. Z. Slawin, J. D. Woollins, Q. Zhang, J. Chem. Soc. Dalton Trans.
2001, 621.
[49] M. Aydemir, A. Baysal, B. Gümgüm, J. Organomet. Chem. 2008, 693, 3810.
[50] O. Akba, F. Durap, M. Aydemir, A. Baysal, B. Gümgüm, S. Özkar,
J. Organomet. Chem. 2009, 694, 731.
[51] I. Özdemir, S. Yaşar, S. Demir, B. Çetinkaya, Heteroat. Chem. 2005, 16, 557.
[52] B. J. Galon, R. W. Kojima, R. B. Kaner, P. L. Diaconescu, Angew. Chem. Int.
Ed. 2007, 46, 7251.
[17] Q. Yang, S. Ma, J. Li, F. Xiao, H. Xiong, Chem. Commun. 2006,
2495.
[18] T. E. Barder, S. D. Walker, J. R. Martinelli, S. L. Buchwald, J. Am. Chem. Soc.
2005, 127, 4685.
[19] W. A. Hermann, Angew. Chem. Int. Ed. 2002, 41, 1290.
[20] D. Zim, S. M. Nobre, A. L. Monteiro, J. Mol. Catal. A 2008, 287, 16.
[21] A. Kilic, F. Durap, M. Aydemir, A. Baysal, E. Taş, J. Organomet. Chem.
2008, 693, 2835.
[22] M. Aydemir, N. Meriç, A. Baysal, M. Toğrul, B. Gümgüm, Tetrahedron:
Asymmetry 2010, 21, 703.
[23] C. Chiappe, C. S. Pomelli, U. Bardi, S. Caporali, Phys. Chem. Chem. Phys.
2012, 14, 5045.
[24] T. Welton, Coord. Chem. Rev. 2004, 248, 2459.
[25] J. P. Hallett, T. Welton, Chem. Rev. 2011, 111, 3508.
[26] A. Corma, H. Garcia, A. Leyva, Tetrahedron 2004, 60, 8553.
[27] S. Lee, Y. J. Zhang, J. Y. Piao, H. Yoon, C. E. Song, J. H. Choi, J. Hong,
Chem. Commun. 2003, 2624.
[53] A. F. Littke, G. C. Fu, Angew. Chem. Int. Ed. 2002, 41, 4176.
[54] E. Negishi, Handbook of Organopalladium Chemistry for Organic
Synthesis, Vol. 1, Wiley, New York, 2002, pp. 17.
[55] R. F. Heck, Palladium Reagents in Organic Synthesis, Academic Press,
New York, 1985.
[56] S. A. Godleski, in Comprehensive Organic Synthesis, vol. 4 (Eds.: B. M. Trost,
I. Fleming, M. F. Semmelhack), Pergamon Press, Oxford, 1991, p. 585.
[57] W. Cabri, I. Candiani, Acc. Chem. Res. 1995, 28, 2.
[58] W. A. Herrmann, C. Broßmer, K. Öfele, C. Reisinger, T. Riermeier,
M. Beller, H. Fischer, Angew. Chem. Int. Ed. 1995, 107, 1989.
[59] A. L. Boyes, I. R. Butler, S. C. Quayle, Tetrahedron Lett. 1998, 39, 7763.
[60] H. Brunner, N. Le Cousturier de Courey, J. P. Genet, Tetrahedron Lett.
1999, 40, 4815.
[28] Z. Fei, D. Zhao, T. J. Geldbach, R. Scopelliti, P. J. Dyson, Chem. Eur. J.
2004, 10, 4886.
[29] I. J. B. Lin, C. S. Vasam, J. Organomet. Chem. 2005, 690, 3498.
[30] D. Drew, J. R. Doyle, Inorg. Synth. 1972, 13, 47.
[31] J. X. McDermott, J. F. White, G. M. Whitesides, J. Am. Chem. Soc. 1976,
98, 6521.
[32] C. Chen, Phys. Chem. Liq. 2010, 48, 298.
[33] K. Rafikova, N. Kystaubayeva, S. Paşa, N. Meriç, Y. S. Ocak, M. Aydemir,
A. Zazybin, H. Temel, Polyhedron 2014, 81, 245.
[61] M. Beller, K. Kühlein, Synlett 1995, 441.
[62] F. Zhao, B. M. Bhanage, M. Shirai, M. Arai, J. Mol. Catal. A 1999, 142, 383.
[34] U. Işık, M. Aydemir, N. Meriç, F. Durap, C. Kayan, H. Temel, A. Baysal,
J. Mol. Catal. A 2013, 379, 225.
[35] M. Aydemir, F. Durap, A. Baysal, N. Meriç, A. Buldağ, B. Gümgüm,
S. Özkar, L. T. Yıldırım, J. Mol. Catal A 2010, 326, 75.
[36] A. Baysal, M. Aydemir, F. Durap, B. Gümgüm, S. Özkar, L. T. Yıldırım,
Polyhedron 2007, 25, 3373.
[37] M. Aydemir, A. Baysal, F. Durap, B. Gümgüm, S. Özkar, L. T. Yıldırım,
J. Organomet. Chem. 2009, 23, 467.
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