Highly efficient [Ni{iPrHNC(S)NP(S)(OiPr)2-1,3-N,S′} 2]/PR3 (R3 = Me3, Me2Ph) complexes for the generation of Ni0 for catalysis

Article abstract of DOI:10.1039/c1dt10056d

We have developed new complexes of the type [Ni{iPrHNC(S)NP(S)(OiPr) ₂-1,3-N,S′}₂]/PR₃ (R₃ = Me₃, Me₂Ph) for the generation of Ni⁰ catalysts which can be used for the catalytic addition of Ph₂S₂ to 1-, 2- and 3-hexynes. A detailed study of the catalytic reaction mechanism suggests two possible pathways for the in situ formation of Ni⁰ species, depending on the presence or absence of water.

Full text of DOI:10.1039/c1dt10056d

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COMMUNICATION
Highly efficient [Ni{iPrHNC(S)NP(S)(OiPr)2-1,3-N,S¢}2]/PR3 (R3 = Me3,
Me2Ph) complexes for the generation of Ni0 for catalysis†
Damir A. Safin,a Maria G. Babashkina,*a Michael Bolteb and F. Ekkehardt Hahnc
Received 12th January 2011, Accepted 22nd March 2011
DOI: 10.1039/c1dt10056d
We have developed new complexes of the type [Ni{iPr-
HNC(S)NP(S)(OiPr)2-1,3-N,S¢}2]/PR3 (R3 = Me3, Me2Ph)
for the generation of Ni0 catalysts which can be used for
the catalytic addition of Ph2S2 to 1-, 2- and 3-hexynes. A
detailed study of the catalytic reaction mechanism suggests
two possible pathways for the in situ formation of Ni0 species,
depending on the presence or absence of water.
During the last few decades there has been an increasing interest
in the palladium catalyzed stereoselective addition of alkyl2S(Se)2
and aryl2S(Se)2 substrates to various alkynes.1 Phosphane ligands
have been extensively used as additional ligands to generate
catalytically active Pd0 species. However, due to the increasing cost
of Pd, cheaper and more readily accessible catalysts are desirable.
Recently, it was established that some NiII salts and complexes in
combination with phosphane ligands are also capable to catalyze
the stereoselective addition of alkyl2S(Se)2 and aryl2S(Se)2 to
alkynes.1h,2 The presence of a phosphane seems to be a necessary
condition to generate the Ni0 species. Thus, the synthesis of new
easily accessible and easy to handle NiII precatalytic systems is a
Chart 1
formidable challenge and of importance.
The synthesis and complexation properties of N-(thio)-
phosphorylated thioamides RC(S)NHP(O)(OiPr)2 (R = p-BrC6H4,
Ph)6 form distorted octahedral complexes with NiII, where two
phosphorylated thioamides and thioureas RC(S)NHP(X)(OR¢)2
deprotonated ligands are coordinated through the sulfur and
(X = O, S) (NTT) towards various metal cations has been studied.3
oxygen atoms of the C S and P O groups, respectively, and
We have undertaken extensive studies into the synthesis of NiII
two neutral forms of the ligands are bonded through the oxygen
complexes with NTT (X = O) ligands and found, that the square-
planar complexes [Ni(NTT)2] exhibit either a 1,3-N,S- or a 1,5-
O,S coordination mode (Chart 1, A and B). It was established,
that intramolecular hydrogen bonds N–H ◊ ◊ ◊ O P are a necessary
atoms of the P O groups (Chart 1, C). Furthermore, the 1,3-
N,S-coordination of the NTT (X = O) ligands towards NiII
allows the synthesis of octahedral complexes by reaction with
additional donor ligands such as 2,2¢-bipyridine (bpy) and 1,10-
condition for the formation of 1,3-N,S-isomers for R = PhHN,
phenanthroline (phen).4e It is important to note, that the NTT
p-MeOC6H4HN, p-BrC6H4HN, iPrHN, tBuHN, cyclo-C6H11HN,
coordination to NiII is further complicated by the possibility
1-AdHN, (4¢-benzo-15-crown-5)HN,4 while 1,5-O,S coordination
that tetrahedrally configured complexes can be obtained as was
takes place when H-bonding in the coordinated anionic ligands
is not possible (R = Et2N, morpholine-N-yl).5 Moreover, N-
recently shown for the complexes [Ni{R2NC(S)NP(S)(OiPr)2}2]
(R = Me, H), which in polar solvents exhibit spectral features for
a tetrahedral complex (colour, paramagnetism), while in unpolar
solvents and in solid form complexes with a trans square-planar
geometry exist (Chart 1, B). Both configurations exhibit clearly a
1,5-S,S¢-coordination.6
Recently we reported the first example of 1,5,7-N,N¢,S-
coordination of the deprotonated chelate ligand in the square-
planar NiII complex [Ni{2-Py(6-Me)NHC(S)NP(S)(OiPr)2}2].
The molecular structure of this complex has not been determined
so far, but from spectroscopic results it is obvious, that the
aInstitut fu¨r Chemie, Anorganische Festko¨rperchemie, Albert-Einstein-
Str. 3a, D-18059, Rostock, Germany. E-mail: maria.babashkina@ksu.ru;
Fax: +49 381 4986390; Tel: +49 381 4986381
bInstitut fu¨r Anorganische Chemie J.-W.-Goethe-Universita¨t, Frankfurt/
Main, Germany
cInstitut fu¨r Anorganische und Analytische Chemie, Westfa¨lische Wilhelms-
Universita¨t Mu¨nster, Corrensstrasse 36, D-48149, Mu¨nster, Germany
† Electronic supplementary information (ESI) available. CCDC reference
numbers 805251, 805252, 805546 and 805547. For ESI and crystallographic
data in CIF or other electronic format see DOI: 10.1039/c1dt10056d
4806 | Dalton Trans., 2011, 40, 4806–4809
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2-pyridyl donors of the ligand are also coordinated in an overall
octahedral complex (Chart 1, D).7 As a preliminary result we have
also reported the formation of the 1,3-N,S-coordination mode in
the trans square-planar NiII complex with the dithio-substituted
NTT ligands.8
In this study we have investigated the formation of octahedral
NiII complexes formed by the addition of a number of phosphanes
to the square-planar complexes [Ni{iPrHNC(S)NP(S)(OiPr)2-
1,3-N,S¢}2] ([NiLI2]) and [Ni{Et2NC(S)NP(S)(OiPr)2-1,5-S,S¢}2]
([NiLII2]). The complexes of type [Ni(PR3)2LI2] (R = Me3, Me2Ph)
have been used to generate Ni0 species used in the catalytic addition
of Ph2S2 to 1-, 2- and 3-hexynes.
Complexes [NiLI,II2] were prepared by following a similar
procedure in each case. First, the ligand selected was deprotonated
in situ using KOH, followed by reaction with NiCl2 (Scheme 1, see
also ESI†). The IR and NMR spectra confirm the formation of
the complexes [NiLI,II2] (see ESI for additional information†).
observed at 298 and 301 nm (e = 187–190 M-1 cm-1), respectively.
These absorptions have been assigned to intraligand transitions.9
Thus, the UV absorptions of the complex [NiLI2] in CH2Cl2 can
be assigned to corresponding intraligand transitions (p–p* or n-
p* type). In the visible region essentially two absorption bands
were observed, one at 532 nm and another being rather invariant
at 649 nm. From the rather low intensities (164–171 M-1 cm-1)
of the two long-wavelength these bands were assigned to ligand
field (d–d) transitions. The UV-Vis absorption spectra of [NiLI2]
in DMF and [NiLII2] in CH2Cl2 and DMF are very similar. For
a CH2Cl2 solution of [NiLII2] the spectrum showed an intense
band at 246–270 nm with an intense shoulder at 265–281 nm in
the UV region, as well as two bands at 531–535 nm and 644–
662 nm accompanied by a shoulder at 438 nm. This spectrum is
very similar to the UV-Vis absorption spectrum of the complex
[Ni{H2NC(S)NP(S)(OiPr)2}2] in CH2Cl2.6 Thus, the behavior of
[NiLI2] in DMF and [NiLII2] in CH2Cl2 and DMF indicate that
the deprotonated ligand LI,II is coordinated exclusively in the 1,5-
S,S¢-mode, at least in the solvent studies.
The different behavior of the complex [NiLI2] in CH2Cl2 might
be explained by the simultaneous presence of the 1,3-N,S- and
1,5-S,S¢-isomers (as indicated by NMR measurements). It is
noteworthy, that bands in the range of 700–800 nm, which are
inherent features of tetrahedral or pseudo-tetrahedral complexes
of NiII,10 were not observed in the electronic spectra of the com-
plexes [NiLI,II2], indicating a negligible contribution for pseudo-
tetrahedral isomers in solution.
Crystals of [NiLI,II2] were obtained by slow evaporation of
the solvent from CH2Cl2–n-hexane solution (see ESI†). The
molecular structures of the complexes are shown in Fig. 1 and
S1,† while selected bond lengths and angles are given in Table S1
(see ESI†).
Fig. 1 Thermal ellipsoid (30%) plot of the complex [NiLI2]. H-atoms, not
involved in hydrogen bonding and short contacts, have been omitted for
clarity.
Complexes [NiLI,II2] crystallize in the triclinic space group P1
¯
and show centrosymmetric structures. The NiII ion is coordinated
in a square-planar fashion with the donor atoms of the ligands
arranged in a trans-configuration (Fig. 1 and S1 in ESI†). The four-
membered Ni–S–C–N metallocycles are planar in [NiLI2]. The six-
Scheme 1 Preparation of the NiII complexes.
Complexes [NiLI,II2] were obtained as dark violet microcrystals.
Dissolving the crystals of [NiLI2] in CH2Cl2 leads to a greenish-
blue solution, while the DMF solution of [NiLI2], and CH2Cl2
and DMF solutions of [NiLII2] are dark green. The spectrum of
[NiLI2] in CH2Cl2 contains two intense bands in the UV region, one
lying at 264 nm, the other one at 331 nm (see ESI†). Absorption
bands for the free and protonated NTT ligands are rather high in
energy (lmaxabs < 250 nm) while the absorption bands of KLI,II were
membered Ni–S–C–N–P–S metallocycles in the complex [NiLII
]
2
adopt an asymmetric boat form. The values of the intracyclic
S–Ni–N angles in the four-membered rings of [NiLI2] fall in the
range of 74–75◦, while the intracyclic S–Ni–S angle in [NiLII
]
2
measures about 99◦. Inspection of the C–S and P–N bond lengths
of [NiLI2] indicates, that these bonds are best described as single
bonds, while the P S distances indicate the presence of a double
bond (Fig. 1).3 A lengthening of the C S and shortening of the
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C–N bonds has been observed upon formation of the complex
[NiLII2] in comparison to the free NTT ligand.3 The same change,
but to a smaller degree, has been observed for the P–N and
Me3, Me2Ph) complexes was observed. The same [Ni(PR3)2(SPh)2]
(R3 = Me3, Me2Ph) complexes were formed using the reaction
of [Ni(COD)2]/PR3 with Ph2S2. We have also examined the
decomposition mechanism of the complexes [Ni(PR3)2LI2] in dry
P
S bonds. The alkyl NH protons in [NiLI2] are involved in
1
1
intramolecular hydrogen bonds of the N–H ◊ ◊ ◊ S P type (Fig.
1). Due to the formation of these hydrogen bonds, flat syn,syn-
conformation of the N–C–N–P–S unit is favored. Furthermore,
there are intermolecular hydrogen contacts of the C–H ◊ ◊ ◊ O–P
and C–H ◊ ◊ ◊ S C types in the complexes [NiLI,II2], respectively
(Fig. 1 and S1 in ESI†). These short contacts lead to the formation
of polymeric chains in the crystal.
and aqueous toluene. According to the 31P{ H} and H NMR
spectroscopy data the complexes decompose until formation
of the disulfide (iPrO)2P(S)–N C(NHiPr)–S–S–C(NHiPr) N–
P(S)(OiPr)2 was observed (Scheme 2). A related formation of
similar disulfides with the generation of Hg0 and Pd0 species
was found earlier.14 Using aqueous toluene in the decomposition
of [Ni(PR3)2LI2] leads to the formation of the HLI ligand (see
ESI†) and the corresponding phosphane oxide R3P O (R3 = Me3,
Me2Ph) (Scheme 2).
We studied the coordination of a number of phosphane ligands
PR3 (R3 = Me3, Me2Et, MeEt2, Me2Ph, MePh2, Et3, Et2Ph, EtPh2,
(nPr)3, (nPr)2Ph, (nPr)Ph2, (iPr)3, (iPr)2Ph, (iPr)Ph2, Cy3, Cy2Ph,
CyPh2, PPh3) to the complexes [NiLI,II2]. According to the NMR
and UV-Vis data it is evident that the complex [NiLII2] does not
form any mixed-ligand compounds. It was also found, that the
complex [NiLI2] forms the mixed-ligand structures exclusively with
two equivalents of the PMe3 and PMe2Ph phosphanes (see ESI†).
Furthermore, according to the NMR and UV-Vis data the reaction
of [NiLI2] with one equivalent of PMe3 or PMe2Ph leads to the
mixture of the starting complex and [Ni(PR3)2LI2] (R3 = Me3,
Me2Ph) with no evidence for the formation of pentacoordinated
derivatives.11 Such a behavior of the complex [NiLI2] might be
due to the coordinatively unsaturated NiII atom in the N2S2
environment together with small S–Ni–N bite angles (Fig. 1)
compared to the S4 coordination environment and considerably
bigger S–Ni–S angles in the complex [NiLII2] (Fig. S1 in ESI†).
Complex [NiLI2] does not form mixed-ligand adducts with another
phosphanes, probably, due to the bulky iPrO substituents (Fig. 1).
It should be noted, that the 1,3-N,S-coordination mode of the
deprotonated NTT ligands in the NiII complexes is conserved in
the mixed-ligand complexes with additional donor ligands bpy
and phen.4e Moreover, the introduction of the bpy or phen ligands
into the coordination sphere of the metal cation of the complexes
[Zn{RC(S)NP(O)(OiPr)2-1,5-O,S}2] (R = H2N, PhHN) leads to
a change from 1,5-O,S- to 1,3-N,S-coordination of the anionic
ligands.12 Dissolving of the complexes [Ni(PR3)2LI2] in acetone,
DMSO or DMF leads to the formation of a mixture of the starting
complex [NiLI2] and free phosphanes. Only traces of the mixed-
ligand complexes are observed in this case.
Scheme 2 Generation of [Ni0(PR3)n] (R3 = Me3, Me2Ph).
We have studied the catalytic reaction of Ph2S2 with 1-, 2- and
3-hexynes (Scheme 3) using the mixed-ligand complex systems
The NMR and IR data of the complexes [Ni(PR3)2LI2] are very
similar and are in accordance with the proposed structures (see
ESI†). A CH2Cl2 solution of [Ni(PR3)2LI2] shows an orange color
and the UV-Vis spectra are characterized by an intense band in
the UV region at 281–285 nm assigned to an intraligand transition
in addition to several weak bands in the range 400–800 nm (see
ESI†). A closer inspection reveals four absorption maxima with
the wavelength band at about 785 nm (e 15–17 M-1 cm-1). The
number of bands and the extremely low intensity is a strong
indication for octahedral NiII species, while the d–d bands of
complexes with tetrahedral geometry usually have e values in the
range 100–300 M-1 cm-1.13
We have also noticed that increasing the temperature of
the toluene solutions containing [Ni(PR3)LI2] to values above
50 ◦C leads to a number of species. To identify the possible
formation of Ni0 we used Ph2S2, according to the described
procedure,2f to trap the Ni0 species by an oxidative addition
Scheme 3 Catalytic addition of Ph2S2 to 1-, 2- and 3-hexynes in toluene
(1 mL) at 100 ◦C (t = 10–12 h; C([NiLI2]) = 0.01 mmol, C(PR3) = 0.1 mmol,
C(hexyne) = 0.75 mmol).
reaction. The formation of the stable [Ni(PR3)2(SPh)2] (R3
=
4808 | Dalton Trans., 2011, 40, 4806–4809
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[Ni(PR3)2LI2] as precatalysts (see ESI†). It is known, that this type
of reaction is catalyzed by Ni0 species.2
Ananikov, N. V. Orlov and I. P. Beletskaya, Organometallics, 2006, 25,
1970; (c) D. A. Malyshev, N. M. Scott, N. Marion, E. D. Stevens, V.
P. Ananikov, I. P. Beletskaya and S. Nolan, Organometallics, 2006,
25, 4462; (d) V. P. Ananikov, N. V. Orlov and I. P. Beletskaya,
Organometallics, 2007, 26, 740; (e) V. P. Ananikov, N. V. Orlov, M.
A. Kabeshov, I. P. Beletskaya and Z. A. Starikova, Organometallics,
2008, 27, 4056; (f) V. P. Ananikov, K. A. Gayduk, Z. A. Starikova and
I. P. Beletskaya, Organometallics, 2010, 29, 5098; (g) V. P. Ananikov, K.
A. Gayduk, N. V. Orlov, I. P. Beletskaya, V. N. Khrustalev and M. Yu.
Antipin, Chem.–Eur. J., 2010, 16, 2063.
3 For examples: (a) F. D. Sokolov, V. V. Brusko, N. G. Zabirov and R.
A. Cherkasov, Curr. Org. Chem., 2006, 10, 27, andreferences therein;
(b) F. D. Sokolov, V. V. Brusko, D. A. Safin, R. A. Cherkasov and
N. G. Zabirov, Coordination Diversity of N-Phosphorylated Amides
and Ureas Towards VIIIB Group Cations, in, B. Varga and L. Kis, ed.
Transition Metal Chemistry: New Research, 2008, p. 101, and references
therein.
4 (a) F. D. Sokolov, N. G. Zabirov, L. N. Yamalieva, V. G. Shtyrlin, R.
R. Garipov, V. V. Brusko, A. Yu. Verat, S. V. Baranov, P. Mlynarz, T.
Glowiak and H. Kozlowski, Inorg. Chim. Acta, 2006, 359, 2087; (b) F.
D. Sokolov, S. V. Baranov, D. A. Safin, F. E. Hahn, M. Kubiak, T.
Pape, M. G. Babashkina, N. G. Zabirov, J. Galezowska, H. Kozlowski
and R. A. Cherkasov, New J. Chem., 2007, 31, 1661; (c) F. D. Sokolov,
S. V. Baranov, N. G. Zabirov, D. B. Krivolapov, I. A. Litvinov, B. I.
Khairutdinov and R. A. Cherkasov, Mendeleev Commun., 2007, 17,
222; (d) D. A. Safin, F. D. Sokolov, Ł. Szyrwiel, M. G. Babashkina, T.
R. Gimadiev, F. E. Hahn, H. Kozlowski, D. B. Krivolapov and I. A.
Litvinov, Polyhedron, 2008, 27, 2271; (e) D. A. Safin, M. G. Babashkina,
A. Klein, F. D. Sokolov, S. V. Baranov, T. Pape, F. E. Hahn and D. B.
Krivolapov, New J. Chem., 2009, 33, 2443.
5 (a) D. A. Safin, F. D. Sokolov, S. V. Baranov, Ł. Szyrwiel, M. G.
Babashkina, E. R. Shakirova, F. E. Hahn and Kozlowski, Z. Anorg.
Allg. Chem., 2008, 634, 835; (b) A. Yu. Verat, V. G. Shtyrlin, B. I.
Khairutdinov, F. D. Sokolov, L. N. Yamalieva, D. B. Krivolapov, N. G.
Zabirov, I. A. Litvinov and V. V. Klochkov, Mendeleev Commun., 2008,
18, 150.
6 (a) D. A. Safin, M. Bolte, M. G. Babashkina and H. Kozlowski,
Polyhedron, 2010, 29, 488; (b) D. A. Safin, M. G. Babashkina, M.
Bolte and Klein, Inorg. Chim. Acta, 2011, 365, 32.
7 M. G. Babashkina, D. A. Safin, M. Bolte and A. Klein, Polyhedron,
2010, 29, 1515.
8 (a) M. G. Babashkina, D. A. Safin, M. Bolte and A. Klein, Inorg. Chem.
Commun., 2009, 12, 678; (b) M. G. Babashkina, D. A. Safin, M. Bolte,
M. Srebro, M. Mitoraj, A. Uthe, Klein and M. Ko¨ckerling, Dalton
Trans., 2011, 40, 3142, DOI: 10.1039/c0dt01382j.
9 (a) D. A. Safin, F. D. Sokolov, H. No¨th, M. G. Babashkina, T. R.
Gimadiev, J. Galezowska and H. Kozlowski, Polyhedron, 2008, 27,
2022; (b) D. A. Safin, A. Klein, M. G. Babashkina, H. No¨th, D. B.
Krivolapov, I. A. Litvinov and H. Kozlowski, Polyhedron, 2009, 28,
1504; (c) D. A. Safin, M. G. Babashkina, M. Bolte, T. Pape, F. E. Hahn,
M. L. Verizhnikov, A. R. Bashirov and A. Klein, Dalton Trans., 2010,
39, 11577.
It was found that the products of the catalytic reaction 1–3
are formed in high yields (96–99%) and with efficient selectivity
from 96/4 to > 99/1 (Scheme 3). However, the addition of Ph2S2
to 1-hexyne has shown the worst selectivity among the studied
alkynes. This might be explained by the higher lability of 1-
hexyne. Furthermore, the isolated yields of 1–3 were 91–95%.
These results are compared with the data for the [NiII(acac)2]
and [Ni0(COD)2] complexes as precatalysts.2f Using the latter
compounds together with PMePh2 in the catalytic addition of
Ph2S2 to 3-hexyne also leads to the formation of 3 in high yield
(99%) and a selectivity of > 99/1. However, this reaction requires
3 h. Furthermore, handling of [Ni(COD)2] is rather complicated
and requires an inert atmosphere. In contrast to this situation, the
complexes [Ni(PR3)2LI2] (R = Me3, Me2Ph) are easily synthesized
and can be isolated with no precautions necessary. They can
be kept in air at least for several months without any signs
of decomposition, while the complex [Ni(PMe2Ph)2(acac)] was
◦
isolated at -17 C and is only stable at low temperature.2f Thus,
the NiII complex [NiLI2] in combination with phosphanes PR3
(R3 = Me3, Me2Ph) yields a highly efficient mixture for the
generation of Ni0 species in situ, which subsequently show a
high catalytic activity in the addition of Ph2S2 to 1-, 2- and 3-
hexynes.
We have synthesized the NiII complexes [Ni{iPrHNC(S)NP-
(S)(OiPr)2-1,3-N,S}2] [NiLI2] and [Ni{Et2NC(S)NP(S)(OiPr)2-
1,5-S,S¢}2] [NiLII2]. The former complex is the first example for a
NiII complex containing an asymmetric NTT ligand featuring an
alkyl-NH substituent at the thiocarbonyl group and coordinating
to the metal in the 1,3-N,S-fashion in the solid state. It was
established that the complex [NiLI2] forms stable mixed-ligand
octahedral complexes with phosphanes PR3 (R3 = Me3, Me2Ph).
These mixed-ligand complexes are efficient precatalysts for the
in situ generation of Ni0 species which were successfully used to
catalyze the addition of Ph2S2 to 1-, 2- and 3-hexynes.
Acknowledgements
D.A.S. and M.G.B. thank Prof. Dr Martin Ko¨ckerling for the
support.
10 (a) A. Davison and E. S. Switkes, Inorg. Chem., 1971, 10, 837; (b) E.
Simon-Manso, M. Valderrama and D. Boys, Inorg. Chem., 2001, 40,
3647.
11 V. V. Brusko, A. I. Rakhmatullin, V. G. Shtyrlin and N. G. Zabirov,
Russ. J. Gen. Chem., 2000, 70, 1521.
12 D. A. Safin, M. G. Babashkina, M. Bolte, D. B. Krivolapov, M. L.
Verizhnikov, A. R. Bashirov and A. Klein, Inorg. Chim. Acta, 2011,
366, 19.
13 (a) S. F. A. Kettle, Physical Inorganic Chemistry: a Coordination
Chemistry Approach, Spektrum Academica Publ., 1996, p. 175; (b) P.
Moore, W. Errington and S. P. Sangha, Helv. Chim. Acta, 2005, 88,
782.
14 (a) N. G. Zabirov, Doctor thesis, Kazan State University, Kazan, Russia,
1995, p. p. 483; (b) V. N. Solov’ev, F. M. Shamsevaleev, R. A. Cherkasov,
A. N. Chekhlov, A. G. Tsifarkin and I. V. Martynov, Russ. J. Gen. Chem.
(USSR), 1991, 61, 657; (c) D. A. Safin, M. G. Babashkina and A. Klein,
Catal. Lett., 2008, 129, 363.
Notes and references
1 For examples: (a) H. Kuniyasu, A. Ogawa, S. Miyazaki, I. Ryu, N.
Kambe and N. Sonoda, J. Am. Chem. Soc., 1991, 113, 9796; (b) T.
Kondo and T. Mitsudo, Chem. Rev., 2000, 100, 3205; (c) E. Negishi,
Ed, Handbook of Organopalladium Chemistry for Organic Synthesis,
Wiley, New York, Chichester, 2002; (d) M. Beller, J. Seayad, A. Tillack
and H. Jiao, Angew. Chem., Int. Ed., 2004, 43, 3368; (e) F. Alonso, I. P.
Beletskaya and M. Yus, Chem. Rev., 2004, 104, 3079; (f) I. Beletskaya
and C. Moberg, Chem. Rev., 2006, 106, 2320; (g) I. P. Beletskaya and
V. P. Ananikov, Eur. J. Org. Chem., 2007, 3431; (h) V. P. Ananikov, K.
A. Gayduk, I. P. Beletskaya, V. N. Khrustalev and M. Yu. Antipin,
Chem.–Eur. J., 2008, 14, 2420.
2 (a) V. P. Ananikov, D. A. Malyshev, I. P. Beletskaya, G. G. Aleksandrov
and I. L. Eremenko, Adv. Synth. Catal., 2005, 347, 1993; (b) V. P.
This journal is
The Royal Society of Chemistry 2011
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©