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were thoroughly dried and degassed. Compound But–
CH@W(NAr)(OCMe2CF3)2 [2c] and Me3GeCH@CH2 [7]
were prepared according to a literature procedure. 1H
NMR and 13C NMR spectra were recorded on a Bruker
DPX-200 NMR spectrometer. The chemical shifts are
reported in parts per million with tetramethylsilane
(0.00 ppm) as the internal standard. The molecular-weight
distribution (MWD) of polynorbornenes was determined
by gel-permeation chromatography (GPC) using a set of
five styrogel columns with a pore diameter of 1 · 105,
3 · 10 , 1 · 10 , 1 · 10 and, 250 A (Waters, USA). The
detector was an R-403 differential refractometer (Waters),
and the eluent was tetrahydrofuran. Narrow-MWD poly-
styrene references were used for calibration. The contents
of cis and trans units in the polymers were determined by
1H and 13C NMR spectroscopy according to a literature
procedure [8–10]. Melting temperatures of the polymers
were determined using differential scanning calorimeter
(NETZSCH DSC 204 F1) using a first heating rate of
10 ꢁC/min from 10 to 80 ꢁC.
and 10.0 Hz, aCHH0), 4.12–4.00 (m 4H, aCHH0, aCH-
GeMe3, CHMe2), 1.61 (d, 6H, OCMe2CF3), 1.51 (d, 6H,
OCMe2CF3), 1.26 (m, 12H, CHMe2), 0.47 (s, 9H, GeMe3),
0.06 (s, 9H, GeMe3), ꢀ0.74 (q, 1H, J ꢁ 9.9 Hz,
bCHGeMe3).
3.4. Metathesis of 1-hexene
The kinetic experiments and determinations of rate con-
stants were performed as described in the literature
[3,11,12]. In a typical experiment to an ampoule containing
35.8 mg of catalyst and connected with gas burette 1.234 g
(1.46 mL) of neat 1-hexene was added in argon atmo-
sphere. The mixture was stirred magnetically. Amount of
ethylene was determined volumometrically.
4
4
3
˚
3.5. Polymerization of cyclooctene
To an ampoule containing 0.045 g (0.061 mmol) of cat-
alyst 1 0.68 g (6.1 mmol) of cyclooctene was added at
room temperature. The mixture was magnetically stirred
and in a less than a minute became light-orange transpar-
ent solid. The polyoctenylene formed was purified three
times by precipitation by methanol from CHCl3 and dried
in vacuum at room temperature until the weight was not
changed. The yield was 0.59 g (88%). Polymerization of
cyclooctene using compound 2 as catalyst was carried
out in similar manner. The polymerization time was 2 h.
From 0.42 g (3.8 mmol) of cyclooctene and 0.08 g
(0.090 mmol) of catalyst 2 0.40 g (92%) of polyoctenylene
was obtained.
3.2. Preparation of (2,6-diisopropylphenylimido)-bis(1,1-
dimethyl-2,2,2-trifluoroethanolato)-
(trimethylgermylmethylidene)-tungsten (1)
A solution of Me3GeCH@CH2 (0.20 g, 1.38 mmol) in
2 mL of benzene was added to a solution of But–
CH@W(NAr)(OCMe2CF3)2 (1.0 g, 1.46 mmol) in 3 mL of
benzene. The reaction mixture was kept at room tempera-
ture for 5 h. Evaporation of the solvent and volatiles in
vacuo and crystallization of the solid residue from pentane
afforded 0.49 g (45.0%) of 1 as bright-yellow crystals. Anal.
Calc. for C24H39F6GeNO2W: C, 38.75; H, 5.28. Found: C,
38.87; H, 5.21%. 1H NMR (200 MHz, C6D6) d 9.57 (s, 1H,
WCHGeMe3), 7.20–6.90 (m, 3H, Harom), 3.67 (sept, 2H,
CHMe2), 1.34 and 1.26 (s, 6H each, OCMe2CF3), 1.24
(d, 12H, CHMe2), 0.23 (s, 9H, WCHGeMe3). 13C NMR
(50 MHz, C6D6) d 231.8 (WCHGeMe3), 152.5 (Cipso),
144.7 (Co), 127.1 (q, JCF = 285 Hz, CF3), 126.6 (Cp),
3.6. Polymerization of norbornene
To an ampoule containing 0.0297 g (0.040 mmol) of cat-
alyst 1 in 2 mL of benzene 0.94 g (10.0 mmol) of norborn-
ene in 3 mL of benzene was added at room temperature.
The mixture was magnetically stirred and in less than a
minute became light-orange transparent viscous and after
that the polynorbornene formed was purified three times
by precipitation by methanol from CHCl3 and dried in vac-
uum at room temperature until the weight was not chan-
ged. The yield was 0.71 g (75%). Polymerization of
norbornene using compound 2 as catalyst was carried out
in similar manner. The polymerization time was 2 min.
From 0.65 g (6.9 mmol) of norbornene and 0.0344 g
(0.039 mmol) of catalyst 2 0.51 g (78%) of polynorbornene
was obtained.
2
122.8 (Cm), 79.9 (q, JCF = 28.8 Hz, OCMe2CF3), 28.2
(OCMe MeCF3), 24.6 (CHMe2), 24.1 (OCMeMeCF3),
23.7 (CHMe2), 1.4 (MoCHGeMe3).
3.3. Preparation of 1-(2,6-diisopropylphenylimido)-1,1-
bis(1,1-dimethyl-2,2,2-trifluoroethanolato)-2,3-
bis(trimethylgermyl)-1-tungstacyclobutane (2)
A solution of Me3GeCH@CH2 (0.65 g, 4.46 mmol) in
2 mL of benzene was added to a solution of But–
CH@W(NAr)(OCMe2CF3)2 (1.5 g, 2.19 mmol) in 5 mL of
benzene. The reaction mixture was kept at room tempera-
ture for 5 h. Slow evaporation of the solvent and volatiles
in vacuo at room temperature led to the formation of
light-brown crystals of 2. The isolated yield was 1.17 g
(60.0%). Anal. Calc. for C29H51F6Ge2NO2W: C, 39.19;
3.7. Crystallographic data for 1 and 2
The data were collected on a Bruker AXS ‘‘SMART
APEX’’ diffractometer (graphite-monochromator, Mo
˚
Ka-radiation, u ꢀ x-scan technique, k = 0.71073 A). The
intensity data were integrated in the SAINT program [13].
SADABS [14] was used to perform area-detector scaling and
absorption corrections. The structures were solved by
1
H, 5.74. Found: C, 39.17; H, 5.77%. H NMR (200 MHz,
C6D6) 7.00–6.65 (m, 3H, Harom), 5.43 (m, 1H, JHH = 4.8
Bochkarev, Leonid N.
