Carbene complexes of molybdenum and tungsten Et3E-CH=M(NAr)(OR) 2 (M = Mo, W; E = Si, Ge) and π-complex of molybdenum (RO) 2(ArN)Mo(CH2=CH-GeEt3). Synthesis and catalytic properties

Article abstract of DOI:10.1134/S1070363210100129

The heteroelement-containing alkylidene imide complexes with molybdenum and tungsten Et₃SiCH=Mo(NAr)(OR)₂ (I), Et₃ ECH=W(NAr)(OR)₂ (E = Si (II), Ge (III); Ar = 2,6-i-Pr ₂C₆H₃; R=CMe₂ CF₃) and π-complex (RO)₂(ArN)Mo(CH₂=CH-GeEt₃) (IV) were synthesized by the reaction of Alkyl-CH=M(NAr) (OR)₂ (M=Mo, W; Alkyl = t-Bu, PhMe₂C) with organosilicon and organogermanium vinyl reagents Et₃ECH=CH₂ (E = Si, Ge). The structure of compounds I-III was determined by X-ray diffraction (XRD). The complexes I-IV are active initiators of metathesis polymerization of cycloolefins.

Full text of DOI:10.1134/S1070363210100129

ISSN 1070-3632, Russian Journal of General Chemistry, 2010, Vol. 80, No. 10, pp. 1945–1953. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © Yu.P. Barinova, A.L. Bochkarev, Yu.E. Begantsova, L.N. Bochkarev, Yu.A. Kurskii, G.K. Fukin, A.V. Cherkasov, G.A. Abakumov,
2010, published in Zhurnal Obshchei Khimii, 2010, Vol. 80, No. 10, pp. 1634–1642.
Carbene Complexes of Molybdenum
and Tungsten Et3E–CH=M(NAr)(OR)2
(M = Mo, W; E = Si, Ge) and π-Complex of Molybdenum
(RO)2(ArN)Mo(CH2=CH–GeEt3).
Synthesis and Catalytic Properties
Yu. P. Barinova, A. L. Bochkarev, Yu. E. Begantsova, L. N. Bochkarev,
Yu. A. Kurskii, G. K. Fukin, A. V. Cherkasov, and G. A. Abakumov
Razuvaev Institute of Organometallic Chemistry, Russian Academy of Sciences,
ul. Tropinina 49, Nizhni Novgorod, 603950 Russia
e-mail: lnb@iomc.ras.ru
Received December 16, 2009
Abstract―The heteroelement-containing alkylidene imide complexes with molybdenum and tungsten
Et3SiCH=Mo(NAr)(OR)2 (I), Et3 ECH=W(NAr)(OR)2 (E = Si (II), Ge (III); Ar = 2,6-i-Pr2C6H3; R=CMe2 CF3)
and π-complex (RO)2(ArN)Mo(CH2=CH–GeEt3) (IV) were synthesized by the reaction of Alkyl–CH=M(NAr)
(OR)2 (M=Mo, W; Alkyl = t-Bu, PhMe2C) with organosilicon and organogermanium vinyl reagents
Et3ECH=CH2 (E = Si, Ge). The structure of compounds I–III was determined by X-ray diffraction (XRD). The
complexes I–IV are active initiators of metathesis polymerization of cycloolefins.
DOI: 10.1134/S1070363210100129
Alkylidene Schrock complexes of the Alkyl–
CH=M(NAr)(OR')2 type (Alkyl = t-Bu, PhMe2C; M =
Mo, W; Ar = 2,6-Pr-i2C6H3, R' = Alkyl, Aryl) [1–4]
belong to the group of the most active catalysts of
olefin metathesis reactions. Their catalytic properties
as well as the composition and structure of products of
metathesis reactions involving molybdenum and
tungsten catalysts essentially depend on the nature of
their ligand environment. The vast majority of the
catalysts of this type include hydrocarbon carbene
fragments. Less studied are similar complexes of
molybdenum and tungsten with heteroelement-
containing carbene fragments [5–11]. We have
previously shown that carbene complexes with silicon
and germanium substituents in the carbene fragments
Me3ECH=M(NAr)(OR)2, Me2PhSi–CH=M(NAr)(OR)2
(M = Mo, W; E = Si, Ge) are catalysts for some
reactions of olefin metathesis, and their catalytic
activity is markedly different from the activity of the
corresponding hydrocarbon analogs [8–11].
In this work new representatives of the hetero-
element-containing carbene complexes of molyb-
denum and tungsten were synthesized, compounds
with triethylsilyl and triethylgermyl substituents in the
carbene fragments, Et3SiCH=Mo(NAr)(OR)2 (I) and
Et3ECH=W(NAr)(OR)2, E = Si (II) or Ge (III). The
complexes I–III were prepared by the reaction of
alkylidene compounds PhMe2C–CH=Mo(NAr)(OR)2
[5] or t-Bu–CH=W(NAr)(OR)2 [6] with organosilicon
or organogermanium vinyl reagents Et3ECH=CH2 (E =
Si, Ge):
pentane, 20°C
Alkyl–CH=M(NAr)(OR)2 + Et3ECH=CH2
I–III
– Alkyl–CH=CH2
M = Mo, Alkyl = PhMe2C; M = W, Alkyl = t-Bu.
1945

1946
BARINOVA et al.
According to the 1H NMR spectroscopy, the
The X-ray study of compounds I–III showed that
they molecular structures are similar. Complexes I and
II are isostructural. The atoms of molybdenum and
tungsten, as well as of silicon and germanium in the
compounds I–III have a distorted tetrahedral coor-
dination (Fig. 1). The bond angles at the molybdenum
and tungsten atoms are in the range 103.64(7)°–111.76(5)°
and 101.7(1)°–111.9(1)°, respectively (Table 1). The
bond angles at the silicon atoms in I and II [107.72(7)°–
110.79(7)°] and germanium atoms in III [107.9(1)°–
110.4(2)°] also have the values characteristic of a
distorted tetrahedron. The organosilicon and organo-
germanium substituents at the carbene carbon atoms in
the complexes I–III are directed toward imide ligands
that corresponds to the syn-conformation of the
complexes. The changes in the Si1–C1 distances in I, II
and Ge1–C1 in III [1.864(2), 1.862(2) Å in I and II,
formation of complex I is completed within 20 h,
complex II, in 5 h, complex III, in 3 days. Yield of
crude products is almost quantitative, however, the
complexes are well soluble in the common organic
solvents and could be separated in an individual state
in 25–46% yield only. The complexes I–III are
unstable in air crystalline compounds of orange
(Mo) or yellow (W) color. As in the previously studied
silicon- and germanium-containing alkylidene molyb-
denum and tungsten complexes [5–11] the signals of
1
Hα atoms in the H NMR spectra of complexes I
(13.22 ppm), II (9.30 ppm), and III (9.49 ppm) appear
as broad singlets shifted downfield approximately by
1.5 ppm in comparison with similar signals of these
metals complexes with hydrocarbon carbene fragments
[5, 6].
C19
C20
C21
C18
C23
C24
C22
C17
C16
C27
C3
C25
C2
N1
F3
C26
C10
O1
M1
E1
C5
C9
F2
C1
C6
C8
C4
O2
F1
H1
C12
C7
C11
C15
C14
F5
F4
C13
F6
The molecular structure of complexes Et3E–CH=M(NAr)(OR)2 (I, M = Mo, E = Si, II, M = W, E = Si, and III, M = W, E = Ge).
Thermal ellipsoids are given with 30% probability.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

CARBENE COMPLEXES OF MOLYBDENUM
1947
Table 1. Principal bond lengths (d, Å) and bond angles (ω,
deg) in complexes I–III
Table 2. Characteristics of polyoctenamers obtained using
initiators I–IIIa
Initiator Yield, % trans:cis, %
M¯w
M¯n
M¯w/M¯n
Bond
M1–C1
M1–N1
M1–O1
M1–O2
E1–C1
I
II
III
77
85
83
5:95
233110 147030 1.59
1437900 515500 2.79
694500 353600 1.96
I
1.888(2)
1.727(1)
1.9036(9)
1.898(1)
1.864(2)
I
1.888(3)
1.736(2)
1.893(2)
1.885(2)
1.862(3)
II
1.892(3)
1.714(2)
1.898(2)
1.891(2)
1.936(3)
III
55:45
31:69
II
III
a
Polymerization in bulk, the ratio of monomer: initiator = 100:1,
the reaction duration to the formation of a solid transparent block
is 50 min in the case of initiator I and 30 min in the case of
initiators II and III.
Angle
the reaction between these reactants proceeds by
entirely different route compared with the reaction of
neophylidene molybdenum complex with triethyl-
vinylsilane. At the reagents ratio 1:1 the reaction is
completed within 10 minutes affording a complex
mixture of products, among which by the method of 1H
NMR spectroscopy the germanium-containing carbene
complex Et3GeCH=Mo(NAr)(OR)2, (Hα, δ = 13.39 ppm)
was identified, but only in ~3% yield. The main
products were asymmetric olefin derivative PhMe2C–
CH=CH–CH2–GeEt3 and π-complex (RO)2(ArN)Mo·
(CH2=CH–GeEt3) (IV), and the reaction mixture
contained unused neophylidene complex PhMe2C–
CH=Mo(NAr)(OR)2 ( ~20% of the original amount).
Reaction of PhMe2C–CH=Mo(NAr)(OR)2 with an
excess of Et3GeCH=CH2 completed within 5 min. In
M1C1E1
M1N1C16
139.75(9)
164.7(1)
140.5(2)
166.3(2)
139.6(2)
173.2(2)
1.936(3) Å in III] correlate with the changes in the
covalent radii of E1 [1.13 Å (Si) in I and II, and 1.19 Å
(Ge) in III] [12]. The distances Mo=C in complex I
[1.888(2) Å] and W=C in II and III [1.888(3),
1.892(3) Å] are comparable with the analogous
distances in the previously described silicon- and
germanium-containing
carbene
complexes
of
molybdenum Me3SiCH=Mo(NAr)(OR)2 [1.889(2) Å]
[5, 8], PhMe2SiCH=Mo(NAr)(OR)2 [1.877(1) Å] [10],
Ph3SiCH=Mo(NAr)(OR)2 [1.883(3) Å] [8], Me3Ge·
CH=Mo(NAr)(OR)2 [1.889(2) Å] [7], Ph3GeCH=Mo·
(NAr)(OR)2 [1.876(2) Å] [7] and tungsten Me3Si·
CH=W(NAr)(OR)2 [1.877(4) Å] [6, 11], PhMe2Si·
CH=W(NAr)(OR)2 [1.888(3) Å] [11]. Me3GeCH=W·
(NAr)(OR)2 [1.882(3) Å] [9]. Bond angles Mo–C–Si
in I [139.75(9)°] and WC–Si in II [140.5(2)°], WC–Ge
in III [139.6(2)°] are almost of the same value. A
minor difference in the structure of germanium-
containing complex III and silicon-containing
compounds I and II is the slightly larger value of the
angle WNC [173.2(2)°] in III as compared with the
MNC angles [164.7(1)°, 166.3 (2)°] in I and II [M =
Mo (I), W (II)].
1
the H NMR spectrum of the reaction mixture in the
alkylidene region (8.0–20.0 ppm), no signals of Hα
atoms of any carbene complexes were present, the
reaction products were germanium-containing olefin
PhMe2C–CH=CH–CH2–GeEt3 and π-complex IV:
PhMe2C–CH=Mo(NAr)(OR)2 + Et3ECH=CH2
excess
C6D6, 20°C
(RO)2(ArN)Mo(CH2=CH–GeEt3)
IV
+ PhMe2C–CH=CH–CH2–GeEt3
After removal of solvent and triethylvinylger-
manium excess from the reaction mixture in a vacuum
at room temperature, the unsaturated derivative
PhMe2C–CH=CH–CH2–GeEt3 was isolated in 94%
yield by fractionation of the residue in a vacuum at
100–110°C. It is a colorless oily substance stable in
While studying the catalytic properties of
complexes I–III we found that they are active
initiators of metathesis bulk polymerization of
cyclooctene at room temperature and cause formation
of high-molecular polyoctenamers (Table 2).
1
air, which is identified using IR, H and 13C NMR
In further studies, we have attempted to synthesize
a germanium-containing carbene complex of molyb-
denum by the reaction of PhMe2C–CH=Mo(NAr)(OR)2
with Et3GeCH=CH2. Unexpectedly, it was found that
spectroscopy, and elemental analysis. We failed to
isolate molybdenum π-complex (RO)2(ArN)Mo·
(CH2=CH–GeEt3) in an individual state, so this
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

1948
BARINOVA et al.
compound was identified by 1H and 13C NMR
spectroscopy as a component in a mixture with
PhMe2C–CH=CH–CH2–GeEt3. According to NMR
data (see Experimental), the π-complex IV exists in
solution at room temperature in the form of two
isomers in the ratio 82:18, which seem to differ in the
location of the CH2=CH–GeEt3 molecule relative to
the imide and alkoxylate ligands:
PhMe2C–CH=CH–CH2–GeEt3 and the molybdenum π-
complex (RO)2(ArN)Mo(CH2=CH–GeEt3). Similar
processes of β-hydride rearrangements of molybdo-
cyclobutane derivatives and the formation of π-
complexes [(CF3)2MeCO]2(ArN)Mo(CH2=CH–SiMe3),
[Benz2Bitet](ArN)Mo(CH2=CH–CMe2Ph) (Benz2BitetH2 =
3,3'-dibenzhydryl-5,5',6,6',7,7',8,8'-octahydro-1,1'-bis-
2-naphthol),
[Biphen](ArN)Mo(CH2=CH–SnBu3)
(BiphenH2 = 3,3'-di-tert-butyl-5,5',6,6'-tetramethyl-1,1'-
biphenyl-2,2'-diol) have been reported previously [14–16].
Ar
N
Ar
N
Note that the π-complex (RO)2(ArN)Mo(CH2=CH–
GeEt3) without its isolation from a mixture with
PhMe2C–CH=CH–CH2–GeEt3 is capable to initiate the
ring-opening metathesis polymerization (ROMP) of
norbornene and its carbazole derivative, 9-(5-bicyclo
GeEt3
Mo
Mo
OR
CH
OR
CH
RO
H2C
RO
H2C
[2.2.1]hept-5-ene-2-yl-pentyl)-9H-carbazole
[NBE–
GeEt3
(CH2)5–Carb]. Norbornene in benzene solution was
polymerized in 2–3 min to form polynorbornene in
96% yield (Mw = 2177400, Mn = 796300, Mw/Mn =
2.73; the content of cis units 74%). The functional
norbornene derivative NBE–(CH2)5–Carb [17] poly-
merized in benzene solution in an hour.
Isomer 1
Isomer 2
It is presumable that the reaction of PhMe2C–
CH=Mo(NAr)(OR)2 with Et3GeCH=CH2 proceeds in
accordance with the Scheme 1.
In accordance with the generally accepted
mechanism of the olefin metathesis [13], in the initial
stages of the reaction of the molybdenum neophyl-
idene compounds with triethylvinylgermanium the
formation occurs of a molybdocyclobutane derivative
containing Et3Ge and PhMe2C substituents at the Cα
atom of the metallocycle. Then probably the β-hydride
rearrangement of the molybdocyclobutane complex
proceeds and its transformation into an intermediate
alkyl hydride compound. In the final step, the second
molecule of triethylvinylgermanium reacts with the
alkyl hydride compound to form eventually the
n
n
K
(CH2)5
N
(CH2)5
N
K = (RO)2(ArN)Mo(CH2=CH–GeEt3).
Ar
unsaturated
germanium-containing
compound
Scheme 1.
Ar
Ar
GeEt3
GeEt3
N
N
N
CH
CH
Mo
Mo
CH2
+ CH2=CH−GeEt3
Mo
CH
CMe2Ph
RO
RO
RO
RO
RO
RO
CH
H
HC
H
CMe2Ph
CMe2Ph
Ar
N
+ CH2=CH−GeEt3
− PhMe2C−CH=CH−CH2−GeEt3
GeEt3
CH
Mo
H2C
RO
RO
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

CARBENE COMPLEXES OF MOLYBDENUM
1949
The carbazole-containing functionalized polynor-
bornene was isolated in 70% yield (Mw = 19000, Mn =
7300, Mw/Mn = 2.60). The resulting polymer is of
practical interest, since it is known [18] that carbazole-
containing polymers are used as hole-conducting
materials in the manufacture of organic light-emitting
diodes.
solvents used were thoroughly purified and degassed.
PhMe2C–CH=Mo(NAr)(OR)2 [5], t-Bu–CH=W(NAr)OR)2
[6], Et3ECH=CH2 (E = Si, Ge) [19], and NBE–(CH2)5–
Carb [17] were synthesized as described in the
literature. Cyclooctene (Aldrich) was degassed before
use and kept over sodium mirror. Necessary amounts
were measured off by condensation in a vacuum.
Norbornene (Aldrich) was used without further
purification.
The initiating ability of the molybdenum π-complex
can be explained by the probable formation of carbene
complexes at the interaction of this compound with
cycloolefins, which subsequently participate in the
stage of the chain growth (Scheme 2).
The NMR spectra of tungsten and molybdenum
complexes in deuterobenzene and of the polymer
samples in deuterochloroform were obtained on a
Bruker DPX-200 spectrometer (1H NMR: 200 MHz,
13C NMR: 50 MHz). NMR spectra of π-complex IV
and PhMe2C–CH=CH–CH2–GeEt3 in deuterobenzene
were obtained on a Bruker Avance III-400 spec-
trometer (1H NMR: 400 MHz, 13C NMR: 100 MHz),
assignment of signals was carried out using a gradient
2D-spectroscopy: proton–proton correlation (GE-
COSY) and proton–carbon correlation (GE-HSQC).
Chemical shifts are shown in parts per million (ppm)
relative to tetramethylsilane as internal reference.
Thus, we have synthesized and structurally charac-
terized new molybdenum and tungsten carbene
complexes with triethylsilyl and triethylgermyl sub-
stituents in the carbene fragments. These compounds
actively initiate metathesis polymerization of
cyclooctene in bulk at room temperature that leads to
the formation of high-molecular polyoctenamers. It is
shown that the reaction of a neophylidene compound
PhMe2C–CH=Mo(NAr)(OR)2 with triethylvinylg-
ermanium leads to the formation of the molybdenum
π-complex (RO)2(ArN)Mo(CH2=CH–GeEt3) capable
to initiate metathesis polymerization of norbornene and
its carbazole-containing functional derivatives.
IR spectrum of compound PhMe2C–CH=CH–CH2–
GeEt3 in the form of a liquid film between plates of
KBr or CaF2 were recorded on a FSM 1201 IR-Fourier
spectrometer.
Molecular mass distribution in the polymers was
determined by gel permeation chromatography (GPC)
on a Knauer chromatograph with a Smartline RID
2300 differential refractometer as detector, with a set
EXPERIMENTAL
All operations were performed in evacuated glass
ampules using common Schlenk technique. The
Scheme 2.
Ar
N
+
GeEt3
2
CH
Mo
RO
RO
H2C
− 2 Et3GeCH=CH2
Ar
N
Ar
N
Ar
N
Ar
N
n
Mo
Mo
Mo
Mo
RO
RO
RO
RO
n+1
OR
OR
OR
OR
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

1950
BARINOVA et al.
Table 3. The main crystallographic data and refinement parameters for the complexes I–III
Parameters
I
C27H45F6MoNO2Si
653.67
II
C27H45F6NO2SiW
741.58
III
C27H45F6GeNO2W
786.08
Empirical formula
Molecular weight
Crystal size, mm
Space group
a, Å
0.45×0.26×0.06
P2(1)/c
0.93×0.74×0.58
P2(1)/c
0.39×0.30×0.20
Pna2(1)
18.3618(15)
13.1897(11)
13.0592(10)
90
10.8531(5)
31.2414(16)
10.5572(5)
90
10.8339(5)
31.2873(15)
10.5856(5)
90
b, Å
c, Å
α, deg
β, deg
118.1360(10)
90
118.2790(10)
90
90
γ, deg
90
Volume, Å3
Z
3156.6(3)
4
3159.9(3)
4
3162.8(4)
4
dcalc, mg m–3
μ, mm–1
1.375
1.559
1.651
0.512
3.752
4.643
Tmin/Tmax
F(000)
0.8022/0.9699
1360
0.1281/0.2195
1488
0.2646/0.4570
1560
2θ, deg
55
52
55
Number of independent reflections (Rint)
R1 [I > 2σ(I)]
29696 (0.0286)
0.0366
26564 (0.0398)
0.0316
28483 (0.0298)
0.0291
wR2 (all data)
0.0863
0.0685
0.0625
Number of refined parameters
GOOF
515
358
343
1.051
1.110
1.073
The residual peaks of electron density, e Å–3
–0.386/0.939
–1.022/1.440
–1.046/2.086
of two Phenomenex columns with the Phenogel
sorbent with pore size 104 and 105 Å (eluent THF,
2 ml min–1, 40°C). The calibration of the columns was
carried out with 13 polystyrene standards. The ratio of
trans- and cis-units in polyoctenamers and poly-
norbornene was determined by 13C NMR spectroscopy
according to known methods [20, 21].
100(2) K. Structures were solved by the direct method
and refined by least-squares method on F2hkl in the
anisotropic approximation for all nonhydrogen atoms.
H atoms at C6 in I and all the hydrogen atoms in II
(except for H1) and III were placed into the
geometrically calculated positions and refined with the
“rider” model, the remaining H atoms were found
from difference synthesis of electron density and
refined isotropically. All calculations were performed
using the program package SHELXTL v. 6.10 [22].
The program SADABS [23] was used to introduce
corrections on extinction. The key bond lengths and
bond angles, the main crystallographic characteristics,
Single crystals of complexes I–III were obtained
by crystallization from pentane. X-ray diffraction
studies of complexes I–III were carried out on a
SMART APEX diffractometer (φ–ω-scan, Mo-Kα-
radiation, λ = 0.71073 Å, graphite monochromator) at
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

CARBENE COMPLEXES OF MOLYBDENUM
1951
and parameters of X-ray experiment are given in
Tables 1 and 3.
(2,6-Diisopropylphenylimido)-bis-(1,1-dimethyl-
2,2,2-trifluoroethanolato)(triethylgermylmethyliden)-
tungsten Et3Ge–CH=W(ArN)(OR)2 (III). To a solu-
tion of t-Bu–CH=W(NAr)(OR)2 (0.56 g, 0.82 mmol)
in 5 ml of pentane was added 0.15 g (0.81 mmol) of
Et3GeCH=CH2 in 2 ml of pentane. The reaction
mixture was stirred for 3 days at room temperature.
The solvent and all volatile products were removed by
evaporation in a vacuum. The residual light brown oily
substance was recrystallized from pentane at –50°C.
Compound III was isolated as unstable in the air
yellow crystals. Yield 0.21 g (30%). 1H NMR
spectrum (C6D6), δ, ppm (J, Hz): 0.87 m (6H,
WCHGeCH2Me3), 1.04 t (9H, WCHGeCH2Me3), 1.26
d (12H, CHMe2), 1.27 and 1.37 s (each 6H,
OCMe2CF3), 3.73 sept (2H, CHMe2), 7.20–6.90 m
(3H, Harom), 9.49 s (1H, WCHGeEt3). 13C NMR
spectrum (C6D6), δ, ppm (J, Hz): 7.4 (Ge–CH2–CH3),
8.3 (Ge–CH2–CH3), 23.8 (CHMe2), 24.0
(OCMeMeCF3), 24.6 (CHMe2 ), 28.3 (OCMeMeCF3),
q 79.7 (OCMe2CF3, 2JCF 28.4,), 122.8 (C-m), 126.6 (C-
p), 127.4 q (CF3, JCF 285.0), 144.7 (C-o), 152.4 (C-
ipso), 227.3 (WCHGeCH2Me3). Found, %: C 41.33; H
5.85. C27H45F6GeNO2W. Calculated, %: C 41.25; H
5.77.
(2,6-Diisopropylphenylimido)-bis(1,1-dimethyl-
2,2,2-trifluoroethanolato)(triethylsilylmethylidene)-
molybdenum Et3SiCH=Mo(NAr)(OR)2 (I). To a
solution of PhMe2C–CH=Mo(NAr)(OR)2 (1.1 g, 1.67
mmol) in 5 ml of pentane was added Et3SiCH=CH2
(0.36 g, 2.53 mmol) in 2 ml of pentane. The reaction
mixture was stirred for 20 h at room temperature. The
solvent and volatile products were removed by
evaporation in a vacuum. After recrystallization of the
residue from a minimum amount of pentane at –50°C
0.50 g (46%) of compound I was obtained as unstable
1
in air orange crystals. H NMR spectrum (C6D6), δ,
ppm (J, Hz): 0.64 q [6H, MoCHSi(CH2Me3)3], 0.91 t
[9H, MoCHSi(CH2Me3)3], 1.21 d (12H, CHMe2), 1.37
and 1.28 s (each 6H, OCMe2CF3), 3.71 sept (2H,
CHMe2), 7.01 s (3H, Harom), 13.22 s (1H, MoCHSiEt3).
13C NMR spectrum (C6D6), δ, ppm (J, Hz): 5.7
(SiCH2CH3), 7.7 (SiCH2CH3), 23.9 (CHMe2), 24.3 and
24.4 (OCMe2CF3), 28.6 (CHMe2), 78.9 q (2JCF 28.6,
OCMe2CF3), 123.2 (C-m), 127.2 q (OCMe2CF3, JCF
285.5), 128.3 (C-p), 145.8 (C-o) , 154.1 (C-ipso),
270.9 (MoCHSiEt3). Found, %: C 49.50, H 7.60.
C27H45F6 MoNO2Si. Calculated, %: C 49.39, H 7.47.
Reaction of PhCMe2CH=Mo(NAr)(OR)2 with
Et3GeCH=CH2. To a solution of PhCMe2CH=
Mo(NAr)(OR)2 (0.17 g, 0.26 mmol) in 1.5 ml of C6D6
was added Et3GeCH=CH2 (0.48 g, 2.60 mmol) in 1 ml
(2,6-Diisopropylphenylimido)-bis(1,1-dimethyl-
2,2,2-trifluoroethanolato)(triethylsilylmethyliden)-
tungsten Et3Si–CH=W(ArN)(OR)2 (II). To a solution
of t-Bu–CH=W(NAr)(OR)2 (0.47 g, 0.69 mmol) in
5 ml of pentane was added 0.10 g (0.71 mmol) of
Et3SiCH=CH2 in 2 ml of pentane. The reaction mixture
was stirred for 5 h at room temperature. The solvent
and volatile products were removed by evaporation in
a vacuum. The residual light brown oily substance was
recrystallized from the minimum amount of pentane at
–50°C. Compound II was isolated as unstable in air
yellow crystals. Yield 0.13 g (25%). 1H NMR
spectrum (C6D6), δ, ppm (J, Hz): 0.66 m [6H, WCHSi
(CH2Me3)3], 0.96 d [9H, WCHSi(CH2Me3)3], 1.24 d
(12H, CHMe2), 1.28 and 1.37 s (each 6H, OCMe2CF3),
3.71 sept (2H, CHMe2), 7.20–6.90 m (3H, Harom), 9.30
s (1H, WCHSiEt3). 13C NMR spectrum (C6D6), δ, ppm
(J, Hz): 6.8 (SiCH2CH3), 7.9 (SiCH2CH3), 23.9
(CHMe2), 24.0 (OCMeMeCF3), 24.6 (CHMe2), 28.3
1
of C6D6. According to the H NMR spectroscopy the
reaction completed within 5 min at room temperature,
and the color of the reaction mixture changed from
dark yellow to dark red. The solvent and excess
Et3GeCH=CH2 were removed by evaporation in a
vacuum at room temperature. Dark red oily residue is a
mixture of (2,6-diisopropylphenylimido)-bis-(1,1-
dimethyl-2,2,2-trifluoroethanolato)(triethylvinyl-
germanium)molybdenum (IV) and 2-methyl-2-
phenyl-5-triethylgermylpent-3-ene. The total yield of
compounds was 0.24 g (94%). NMR studies showed
that the π-complex IV in a solution in C6D6 is in the
form of two isomers in 82:18 ratio. Isomer 1 (82%).
1H NMR spectrum (C6D6), δ, ppm (J, Hz): 0.76 q (6H,
GeCH2CH3), 1.03 m (9H, GeCH2CH3), 1.35 and 1.31 s
(each 6H, OCMe2CF3), 1.22 d (12H, CHMe2), 1.98 t
2
3
(OCMeMeCF3), 80.0 q (OCMe2CF3, JCF 29.1), 122.9
(1H, CH2=CHGeEt3, JHH 14.6), 2.59 m (2H,
3
CH2=CHGeEt3, 3JHH 14.8), 3.85 sept (2H, CHMe2 JHH
(C-m), 126.7 (C-p), 127.1 q (CF3, JCF 285.2), 144.9 (C-
o), 152.0 (C-ipso), 225.9 (WCHSiSH2Me3). Found, %:
C 43.84; H 6.18. C27H45F6NO2SiW. Calculated, %: C
43.73; H 6.12.
6.8), 6.96 br.s (3H, Harom). 13C NMR spectrum (C6D6),
δ, ppm (J, Hz): 6.0 (CH2CH3), 9.3 (GeCH2CH3), 23.5
and 24.16 (OCMe2CF3), 28.6 (CHMe2), 28.9 and 29.4
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 10 2010

1952
BARINOVA et al.
(CHMe2), 57.3 (CH2=CHGeEt3), 59.7 (CH2=CHGeEt3)
the addition of benzaldehyde (0.5 g) and precipitated
with methyl alcohol. The formed polymer was
additionally purified by reprecipitation with methanol
from THF and dried in a vacuum at room temperature
to constant weight. Yield of the polymer was 0.23 g
(77%).
2
78.6 q (OCMe2CF3, JCF 28.5) 80.81 q (OCMe2CF3,
1
2JCF 28.9), 123.1 (C-m), 127.5 q (OCMe2CF3, JCF
285.5), 128.0 (C-p), 146.9 (C-o), 153.98 (C-ipso).
Isomer 2 (18%). 1H NMR spectrum (C6D6), δ, ppm (J,
Hz): 0.76 q (6H, Ge–CH2–CH3), 1.03 m (9H,
GeCH2CH3), 1.35 and 1.31 s (each 6H, OCMe2CF3),
1.22 d (12H, CHMe2), 2.19 d.d (1H, CH2=CHGeEt3,
Experiments on the polymerization of cyclooctene
with the initiators II and III were carried out similarly.
3
3
2JHH 3.8, JHH 14.0), 2.85 t (1H, CH2=CHGeEt3, JHH
2
3
Metathesis polymerization of norbornene using
π-complex IV. In an ampule containing 0.03 g
(0.04 mmol) of π-complex IV (as an equimolar
mixture with PhMe2C–CH=CH–CH2–GeEt3) in 1 ml
of benzene at room temperature was added 0.60 g
(6.38 mmol) of norbornene in 1 ml of benzene. After
3 min the reaction mixture became a viscous mass. The
resulting polymer was dissolved in THF with the
addition of benzaldehyde to decompose the catalyst,
and precipitated with methanol. The polymer obtained
was additionally purified by reprecipitation with
methanol from THF and dried in a vacuum at room
temperature to a constant weight. Yield of the polymer
0.57 g (96%).
13.8), 3.16 d.d (1H, CH2=CHGeEt3, JHH 3.6, JHH
3
14.0), 3.85 sept (2H, CHMe2 JHH 6.8), 6.96 br.s (3H,
H
arom). 13C NMR spectrum (C6D6), δ, ppm (J, Hz): 6.09
(CH2–CH3), 9.5 (GeCH2CH3), 23.5 and 24.16
(OCMe2CF3), 28.6 (CHMe2), 28.9 and 29.4 (CHMe2),
55.9 (CH2=CHGeEt3), 61.9 (CH2=CHGeEt3), 78.6 q
2
2
(OCMe2CF3, JCF 28.5), 80.81 q (OCMe2CF3, JCF
1
28.9), 123.1 (C-m), 127.5 q (OCMe2CF3, JCF 285.5),
128.0 (C-p), 146.9 (C-o) , 153.98 (C-ipso).
2-Methyl-2-phenyl-5-triethylgermylpent-3-ene.
After fractionation of the reaction mixture in a vacuum
at 100–110°C unsaturated derivative PhMe2C–
CH=CH–CH2–GeEt3 was isolated as stable in air
colorless oily substance. Yield 0.07 g (94%). IR
spectrum ν, cm–1: 3082 w, 3060 w, (Carom–H), 3023 w
(H–C=CH), 2959 s, 2906 s, 2872 s. (CH3, CH2), 1650
w (C=C, trans), 1601 w, 1492 w (Carom–Carom), 1462 m,
1380 m (CH3, CH2), 1430 w (Carom–Carom), 1260 w,
1138 w (Carom–H), 969 m (HC=CH), 765 m (Car1om–H),
574 m (GeEt3), 547 w (GeEt3). The signals in H and
13C NMR spectra of the isolated compound correspond
to the signals of PhMe2C–CH=CH–CH2–GeEt3 in the
reaction mixture prior to fractionation. 1H NMR
spectrum (C6D6), δ, ppm (J, Hz): 0.74 q (6H,
GeCH2CH3), 1.01 t (9H, GeCH2CH3), 1.37 s (6H,
CMe2Ph), 1.64 d (2H, CH2GeEt3), 5.47 m (2H,
CH=CH), 7.16 t (1, Harom), 7.28 t (2H, Harom), 7.36 d
(2H, Harom). 13C NMR NMR spectrum (C6D6), δ, ppm:
4.1 (GeCH2CH3), 9.1 (GeCH2CH3), 17.1 (CH2GeEt3),
29.3 (CMe2Ph), 40.5 (CMe2Ph ), 123.9 (CH=CH),
125.6 (C-p), 126.3 (C-o), 128.0 (C-m), 137.8
(CH=CH), 149.9 (C-ipso). Found,%: C 68.21, H 9.71.
C18H30Ge. Calculated, %: C 67.80, H 9.44.
Metathesis polymerization of NBE–(CH2)5–Carb
using π-complex IV. In an ampule containing 0.03 g
(0.04 mmol) of π-complex IV (equimolar mixture with
PhMe2C–CH=CH–CH2–GeEt3) in 1 ml of benzene at
room temperature was added 0.10 g (0.30 mmol) of
NBE–(CH2)5–Carb in 1 ml of benzene. The mixture
was stirred at room temperature. After 1 h the reaction
mixture became a viscous mass. The resulting polymer
was isolated as described above. We obtained 0.07 g
(70%) of carbazole-contaning functionalized polynor-
1
bornene, a light-brown powdery substance. H NMR
spectrum (CDCl3), δ, ppm: 1.01–2.23 m (10H), 2.35–
2.81 m (2H), 4.88–5.65 m (3H), 7.20–7.39 m (6H),
8.07 br.s (2H). 13C NMR spectrum (CDCl3), δ, ppm:
27.60, 29.09, 31.80, 43.20, 108.88, 118.84, 120.50,
122.94, 125.70, 140.543.
ACKNOWLEDGMENTS
This work was supported by Russian Foundation
for Basic Research (project no. 08-03-00436, 09-03-
97034-r_Povolzhye_a).
Metathesis polymerization of cyclooctene using
initiators I–III. In an ampule containing 0.0173 g
(0.026 mmol) of initiator I was added 0.30 g
(2.68 mmol) of cyclooctene. The mixture was stirred at
room temperature. During 50 min formed a solid
transparent block. The reaction mixture was
additionally kept at room temperature for 1 h. The
resulting polymer was dissolved in 50 ml of THF with
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