Synthesis and mass spectrometric study of α,ω- diallylpermethyloligosilanes

Article abstract of DOI:10.1007/s11172-005-0104-z

Representatives of the homologous series of α,ω- diallylpermethyloligosilanes were synthesized for the first time by the reaction of α,ω-dichloropermethyloligosilanes Cl(Me₂Si) _nCl (n = 2-6) with allylmagnesium chloride. Fragmentation of α,ω-diallylpermethyloligosilanes under electron impact ionization was studied by mass spectrometry.

Full text of DOI:10.1007/s11172-005-0104-z

2224
Russian Chemical Bulletin, International Edition, Vol. 53, No. 10, pp. 2224—2228, October, 2004
Synthesis and mass spectrometric study
of α ,ωꢀdiallylpermethyloligosilanes
ꢀ
D. Yu. Larkin, A. P. Pleshkova, E. G. Kononova, N. A. Chernyavskaya, and A. I. Chernyavskii
A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
2
8 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (095) 135 5085. Eꢀmail: chern@ineos.ac.ru
Representatives of the homologous series of α,ωꢀdiallylpermethyloligosilanes were syntheꢀ
sized for the first time by the reaction of α,ωꢀdichloropermethyloligosilanes Cl(Me Si) Cl
2
n
(
n = 2—6) with allylmagnesium chloride. Fragmentation of α,ωꢀdiallylpermethyloligosilanes
under electron impact ionization was studied by mass spectrometry.
Key words: α,ωꢀdichloropermethyloligosilanes, allylmagnesium chloride, α,ωꢀdiallylꢀ
permethyloligosilanes, NMR spectra, IR spectra, UV spectra, mass spectra.
α,ωꢀDiallylpermethyloligosilanes are used as the startꢀ
OH, etc.), which were prepared in the crystalline state,
diallylhexasilane 2e, like diallyloligosilanes 2a—d, is a
colorless transparent liquid.
ing compounds for the synthesis of polycarbosilanes,
which are of considerable practical importance as ceꢀ
1
ramicꢀforming polymers. However, data on the preparaꢀ
The structures of oligomers 2a—e were studied by
1
29
tion of such oligomers are scarce. Only the syntheses of
,2ꢀdiallyltetramethyldisilane by thermal isomerization of
,2ꢀcyclopropyltetramethyldisilane2 (7.0% yield), coꢀ
H and Si NMR, IR, UV, and Raman spectroscopy. In
2
9
1
1
the Si NMR spectra of oligomers 2a—e, the signals for
the Si , Si , and Si atoms are shifted downfield as the
a
b
c
condensation of allyldimethylchlorosilane and vinylꢀ
dimethylchlorosilane with magnesium (2.4% yield), and
number of sequentially linked Si atoms increases (Table 1).
3
The IR and Raman spectra of oligomers 2a—e (see
–
1
the reaction of allylmagnesium bromide with 1,2ꢀdiꢀ
Table 1) show intense lines at 1630 cm characteristic
4
5
chlorotetramethyldisilane (the yield was not reported)
of C=C stretching vibrations of allylsilanes. In addiꢀ
were described.
tion, the Raman spectra have lines corresponding to
Si—Si stretching vibrations of oligosilanes in regions of
360—400 cm (symmetric vibrations) and 440—500 cm
(antisymmetric vibrations).6
In the present study, we synthesized representatives of
the homologous series of α,ωꢀdiallylpermethyloligosilanes
All(Me Si) All (2a—e) by the reaction of α,ωꢀdichloroꢀ
–1
–1
2
n
permethyloligosilanes Cl(Me Si) Cl (1a—e) with allylꢀ
Oligomers 2a—e absorb in the UV region. The posiꢀ
tion of the absorption maximum λmax depends on the
2
n
magnesium chloride, examined the spectroscopic characꢀ
teristics of the resulting oligomers, and studied their fragꢀ
mentation under electron impact (EI) ionization.
number of the SiMe groups in oligosilanes 2a—e, and
2
λmax is shifted bathochromically as the number of these
groups increases (see Table 1).
Results and Discussion
Mass spectrometric study of diallyloligosilanes 2a—e.
The fragmentation of oligomers 2a—e and, for compariꢀ
son, of diallyldimethylsilane All SiMe (3) under elecꢀ
The reaction was carried out in Et O at the boiling
2
2
2
temperature of the solvent. The yields of oligomers 2a—e
were 50—75% (Scheme 1).
tron impact (EI) ionization was studied by GLCꢀmass
spectrometry. Silane 3 is formally the first member of the
homologous series of diallyloligosilanes, which differ by
one SiMe2 unit, but it contains no Si—Si bonds. The
fragmentation of silane 3, analogously to fragmentation
Scheme 1
7
of other silanes, occurs with elimination of the Me and
All groups from the Si atom (Table 2). In the mass spectra
of oligomers 2a—e, in contrast to the mass spectrum of
silane 3, the intensity of the molecular ion peak [M] is
n = 2 (a), 3 (b), 4 (c), 5 (d), 6 (e)
+
As distinct from other nonfunctional and bifunctional
permethylhexasilanes X(Me Si) X (X = Me, Ph, Cl,
low (see Table 2), which is typical also of certain monoꢀ
and bifunctional linear permethyloligosilanes. For exꢀ
2
6
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2129—2132, October, 2004.
066ꢀ5285/04/5310ꢀ2224 © 2004 Springer Science+Business Media, Inc.
1

Synthesis of α,ωꢀdiallylpermethyloligosilanes
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 10, October, 2004
2225
Table 1. Selected spectroscopic characteristics of oligomers 2a—e
Compounda
29Si NMR, δ
IR, ν/cm
b
–1
Raman spectrum, ∆ν/cm
b
–1
UV spectrum,c
C=C
λmax/nm
Sia
Sib
Sic
C=C
Si—Si
AllSi SiAll (2a)
–17.45
–14.57
–14.19
–13.88
—
—
—
—
–40.12
–38.59
1634
1627
1634
1627
1634
1632
1630
1630
1630
1632
400
380, 457
368, 473
362, 442, 478
360, 478
223
230
239
254
262
a
AllSi Si SiAll (2b)
–47.17
–43.94
–42.20
–42.02
a
b
AllSi Si SiSiAll (2c)
a
b
AllSi Si Si SiSiAll (2d)
a
b
c
AllSi Si Si SiSiSiAll (2e) –13.80
a
b
c
a
b
c
The Me groups at the Si atoms are omitted.
The complete spectra are given in the Experimental section.
Without a solvent.
Table 2. Mass spectra of diallyloligosilanes 2a—e and compound 3
Ion m/z (Irel (%))
2
a
2b
2c
2d
2e
3
[
[
[
[
[
[
[
A
B
C
D
E
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
[
M ]+
M – Me]
M – All]+
M – Me – C H ]
M – All – C H ]
M – All – C H ]
M – All – C H ]
198 (1.3)
183 (0.8)
157 (100.0)
155 (12.9)
131 (17.2)
129 (83.5)
117 (30.6)
99 (20.7)
256 (1.1)
241 (0.9)
215 (71.1)
213 (1.8)
189 (1.6)
187 (12.3)
175 (1.4)
99 (27.0)
157 (44.8)
—
314 (1.8)
299 (0.8)
273 (6.2)
—
372 (1.1)
357 (0.2)
331 (1.1)
—
430 (0.9)
415 (0.0)
389 (0.6)
—
140 (3.5)
125 (19.2)
99 (100.0)
97 (61.6)
73 (38.1)
71 (48.9)
59 (47.1)
—
+
+
2
4
+
—
—
—
—
—
—
—
—
—
2
2
+
+
2
4
3
4
99 (23.0)
157 (79.0)
215 (77.5)
—
99 (16.1)
157 (35.6)
215 (40.4)
273 (0.5)
—
99 (21.1)
157 (32.8)
215 (97.9)
273 (8.1)
331 (0.7)
83 (8.7)
73 (85.7)
71 (8.7)
141 (100.0)
131 (37.6)
129 (36.2)
127 (41.9)
117 (28.9)
199 (55.9)
185 (34.2)
175 (16.8)
173 (19.5)
257 (11.3)
243 (11.3)
315 (9.3)
289 (6.1)
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
A – CH ]+
A – C H ]
A – C H ]
B – CH4]
B – C H ]
B – C H ]
B – C H ]
B – C H ]
C – CH4]
C – C H ]
C – C H ]
C – C H ]
D – CH4]
D – C H ]
E – CH4]
E – C H ]
83 (15.2)
73 (92.9)
71 (13.9)
83 (7.3)
73 (81.2)
71 (5.2)
141 (100.0)
131 (43.7)
129 (46.4)
127 (72.9)
117 (30.6)
—
83 (7.2)
73 (100.0)
71 (5.4)
141 (99.6)
131 (63.9)
129 (53.3)
127 (43.5)
117 (41.0)
199 (78.7)
185 (54.1)
175 (8.1)
173 (14.6)
—
83 (5.9)
73 (64.9)
71.0 (8.0)
141 (100.0)
131 (36.3)
129 (36.8)
127 (35.5)
117 (29.4)
199 (45.6)
185 (29.1)
175 (6.7)
173 (11.9)
257 (7.2)
243 (8.7)
—
4
+
2
2
+
2
4
+
—
—
—
—
—
—
—
—
—
—
—
—
—
+
+
+
+
2
2
2
4
2
6
3
4
+
+
+
+
—
—
—
—
—
—
—
2
6
3
4
3
6
+
—
—
—
—
+
—
—
—
2
6
+
+
—
3
6
+
ample, the intensity of the [M] peak in the mass spectra
For oligomers 2a—e, the main fragmentation pathꢀ
ways of the [M] ion involve elimination of the Me and
8
,9
+
of halogenꢀcontaining oligosilanes, viz., 1ꢀchloroperꢀ
methyloligosilanes Cl(SiMe ) Me (n = 2—4 and 6)
All groups from the Si atom and the Si—Si bond cleavage.
2
n
+
and α,ωꢀdihalopermethyloligosilanes Hal(SiMe ) Hal
The intensities of the ion peaks [M – Me] in the mass
2
n
(
Hal = Cl, Br, or I; n = 2—6), is 0.1—2.8%. By contrast,
spectra of oligomers 2a—e, unlike those in the spectra of
simple silanes and compound 3, are low and decrease
virtually to zero in going from oligomer 2a to 2e (i.e., as
+
the [M] peaks in the mass spectra of permethyloligoꢀ
silanes10 Me(SiMe ) Me (n = 3—5) have a higher intenꢀ
2
n
sity (15—21%).
the number of SiMe units increases). The allyl group is
2

2226
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 10, October, 2004
Larkin et al.
eliminated more readily than the methyl group, and the
ion peaks [M – All]+ in the mass spectra of disilane 2a
and trisilane 2b have a high intensity. However, in this
containing one, two, and three Si atoms, respectively, are
most intense (16—98%), whereas the intensity of the peaks
of the ions D and E with n = 4 or 5 is low (0.5—8%) (see
Table 2).
case an increase in the number of SiMe units to four—six
2
(
oligomers 2c—e) also leads to a sharp decrease in the
In the case of other linear oligosilanes, the formation
+
intensity of these ion peaks (see Table 2). Suppression of
elimination of the substituents at the Si atom with inꢀ
creasing chain length is common to linear permethylꢀ
oligosilanes10 and halooligosilanes, which is associated
with a lower energy of the Si—Si bond compared to that
of the Si—C bond and, consequently, with the occurꢀ
rence of alternative fragmentation pathways. Actually, the
mass spectra of oligomers 2a—e show intense ion peaks
corresponding to the Si—Si bond cleavage. For example,
fragmentation of the [M] ion of oligomer 2e gives rise to
the ions A, B, C, D, and E of the [All – (SiMe ) ] type
(
the homologous SiMe unit (Scheme 2). In the mass specꢀ
tra of oligomers 2a—e, the peaks of the ions A, B, and C
of the [X(SiMe ) ] ions (X = Me or Hal) is also the
2
n
8
—10
major process.
For example, the intensities of the
corresponding ion peaks at m/z 189, 131, and 73 in
8,9
10
the spectrum of decamethyltetrasilane are 34.3, 53.0,
and 100%, respectively.
Presumably, the ions A—E can be formed both through
the direct cleavage of the Si—Si bonds in the molecular
ion and through the successive fragmentation of the ions
E → D → C → B → A with elimination of the silylene
+
group Me Si. In addition, the fragment ions correspondꢀ
2
+
ing to elimination of the substituents at the Si atom, viz.,
2
n
+
+
n = 1—5, respectively), which differ from each other by
[M – Me] and [M – All] , can serve as a source of the
1
0
ions A—E. For permethyloligosilanes and α,ωꢀdihaloꢀ
permethyloligosilanes, similar fragmentation processes
2
8
,9
Scheme 2

Synthesis of α,ωꢀdiallylpermethyloligosilanes
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 10, October, 2004
2227
were confirmed by the results of studies of metastable
ated. The yield of diallyldisilane 2a was 3.17 g (60.0%), b.p.
6—78 °C (10 Torr). Found (%): C, 60.87; H, 11.28; Si, 27.85.
10H Si . Calculated (%): C, 60.52; H, 11.17; Si, 28.31.
7
C
1
transitions. Elimination of silylene Cl Si from the moꢀ
2
lecular and fragment ions was observed also in the course
22
2
+
H NMR, δ: 0.18 (s, 12 H, 4 Me); 1.72 (d, 4 H, 2 CH2, J =
of fragmentation of [M]
chlorooligosilanes.11
of α,ωꢀdihydridoperꢀ
8
2
1
.1 Hz); 4.95 (d, 4 H, 2 =CH , J = 14.5 Hz); 5.83—5.94 (m,
2
H, 2 CH). IR, ν/cm– : 3077 (ν(=CH)); 2953, 2891 (ν(CH));
1
Further fragmentation of the fragment ions
634 (ν(C=C)); 1425, 1253 (δ(CH )); 1154 (δ(SiCH)); 895
3
+
+
[
M – Me] , [M – All] , A—E, compound 3, and
–1
(
ρ(=CH )); 830, 796, 646 (ν(SiC)). Raman spectrum, ∆ν/cm :
2
diallyloligosilanes 2a—e is accompanied to a greater or
lesser extent by elimination of hydrocarbon molecules
3082 (ν(=CH)); 2954, 2893 (ν(CH)); 1632 (ν(C=C)); 1424,
1392, 1299 (ρ(CH )); 1150 (δ(SiCH)); 990 (ρ(CH=CH ));
3
2
(
CH , C H , C H , C H , C H , and C H ) in accorꢀ
931 (ρ(=CH2)); 696, 657, 582 (ν(SiC)); 410 (δ(CC=C));
00 (ν(SiSi)).
,3ꢀDiallylhexamethyltrisilane (2b). Diallyltrisilane 2b was
prepared according to the aboveꢀdescribed procedure from Mg
2.18 g, 89.7 mmol), AllCl (6.24 g, 81.6 mmol), and dichloroꢀ
trisilane 1b (5.0 g, 20.4 mmol) in a yield of 3.4 g (65.1%), b.p.
5—47 °C (0.5 Torr). Found (%): C, 56.45; H, 11.27; Si, 32.28.
12H28Si . Calculated (%): C, 56.17; H, 11.00; Si, 32.83.
4
2
2
2
4
2
6
3
4
3
6
4
dance with the parity rule (see Table 2). It can be hypothꢀ
esized that these fragmentation pathways involve decomꢀ
position of the allyl group, because elimination of hydroꢀ
carbon molecules from fragment ions of α,ωꢀdihaloꢀ
oligosilanes8 and permethyloligosilanes was not obꢀ
served. By contrast, the fragment ions in the mass spectra
of 1,1,2,2,3,3ꢀhexaethyltrisilane and 1ꢀtriethylsilylhexaꢀ
ethyltrisilane12 are characterized by the fragmentation with
successive elimination of ethylene and ethane molecules.
Therefore, the main fragmentation pathway of oligoꢀ
mers 2a—e under EI ionization involves elimination of
the methyl and allyl substituents at the Si atom and the
Si—Si bond cleavage, the intensities of the resulting ions
1
(
,9
10
4
C
1
3
H NMR, δ: 0.30 (s, 12 H, 4 Me); 0.35 (s, 6 H, 2 Me); 1.84 (d,
4 H, 2 CH , J = 8.4 Hz); 5.02 (d, 4 H, 2 =CH , J = 13.4 Hz);
2
2
–
1
5.94—6.07 (m, 2 H, 2 CH). IR, ν/cm : 3080 (ν(=CH)); 2950,
891 (ν(CH)); 1627 (ν(C=C)); 1400, 1248 (δ(CH )); 1151
2
3
(
δ(SiCH)); 897 (ρ(=CH )); 832, 789, 724, 649 (ν(SiC)). Raman
2
–
1
spectrum, ∆ν/cm : 3080 (ν(=CH)); 2953, 2903 (ν(CH)); 1630
(
(
ν(C=C)); 1418, 1395, 1299, 1240, 1194 (ρ(CH )); 1152
3
δ(SiCH)); 990 (ρ(CH=CH )); 931 (ρ(=CH )); 725, 687, 658,
2
2
being determined by the number of SiMe units in the
oligomer molecules.
2
638 (ν(SiC)); 457, 380 (ν(SiSi)); 403 (δ(CC=C)).
,4ꢀDiallyloctamethyltetrasilane (2c). Analogously to the synꢀ
1
thesis of diallyldisilane 2a, diallyltetrasilane 2c was prepared
from Mg (1.07 g, 44 mmol), AllCl (3.06 g, 40 mmol), and
dichlorotetrasilane 1c (3.03 g, 10 mmol) in a yield of 2.0 g
Experimental
(
63.7%), b.p. 81—83 °C (0.5 Torr). Found (%): C, 53.74;
The H and 29Si NMR spectra were recorded on a Bruker
1
H, 11.02; Si, 35.24. C14H34Si . Calculated (%): C, 53.42;
H, 10.89; Si, 35.69. H NMR, δ: 0.05 and 0.20 (both s, 12 H each,
8 Me); 1.58 (d, 4 H, 2 CH , J = 8.8 Hz); 4.77 (d, 4 H, 2 =CH ,
J = 14.5 Hz); 5.50—5.85 (m, 2 H, 2 CH). IR, ν/cm : 3077
(ν(=CH)); 2953, 2891 (ν(CH)); 1634 (ν(C=C)); 1402, 1249
(δ(CH )); 1153 (δ(SiCH)); 892 (ν(=CH )); 836, 779, 734, 643
(ν(SiC)). Raman spectrum, ∆ν/cm : 3081 (ν(=CH)); 2954,
2896 (ν(CH)); 1630 (ν(C=C)); 1415, 1398, 1299, 1241 (ρ(CH ));
4
1
WPꢀ400 SY spectrometer in CDCl with Me Si as the internal
standard. The IR spectra were measured in a 400—3700ꢀcm
region on a Specord Mꢀ82 spectrophotometer in a thin layer
between KBr glasses. The UV spectra were recorded in a
00—335ꢀnm region on a Specord Mꢀ40 spectrophotometer.
The Raman spectra were measured in a 200—4000ꢀcm region
on a Tꢀ64000 spectrometer (Jobin Yvon) equipped with a CCD
detector (the exciting wavelength was 514.5 nm). The GLCꢀmass
spectrometric analysis was carried out on an HPꢀ5890 instruꢀ
ment (20 m × 0.32ꢀmm capillary column, SEꢀ30 liquid phase,
helium as carrier gas, the temperature of the injector and transiꢀ
tion lines was 250 °C, ionizing voltage was 70 eV, temperature
programming from 60 to 300 °C at a rate of 7 K min– ).
3
4
–
1
2
2
–
1
2
3
2
–
1
–1
3
1152 (δ(SiCH)); 894 (ν(=CH )); 743, 726, 685, 660 (ν(SiC));
473, 368 (ν(SiSi)); 409 (δ(CC=C)).
2
1,5ꢀDiallyldecamethylpentasilane (2d). Analogously to the
synthesis of diallyldisilane 2a, diallylpentasilane 2d was preꢀ
pared from Mg (0.89 g, 36.5 mmol), AllCl (2.54 g, 33.2 mmol),
and dichloropentasilane 1c (3.0 g, 8.3 mmol) in a yield of 2.3 g
(74.4%), b.p. 99—101 °C (0.4 Torr). Found (%): C, 51.82;
1
Dichlorooligosilanes 1a—e were synthesized according to a
procedure described earlier.13 Diallyldimethylsilane (3) was synꢀ
thesized according to a known procedure (86% yield). Diethyl
H, 10.95; Si, 37.23. C16H40Si . Calculated (%): C, 51.53;
H, 10.81; Si, 37.66. H NMR, δ: 0.25 and 0.33 (both s, 12 H each,
5
4
1
ether was dehydrated by refluxing followed by distillation under
a stream of N2 over metallic sodium in the presence of benꢀ
zophenone. All reactions were carried out under dry argon.
8 Me); 0.38 (s, 6 H, 2 Me); 1.78 (d, 4 H, 2 CH , J = 8.1 Hz);
2
5.03 (d, 4 H, 2 =CH , J = 13.5 Hz); 5.70—6.15 (m, 2 H, 2 CH).
2
IR, ν/cm– : 3080 (ν(=CH)); 2945, 2891 (ν(CH)); 1627
1
1
,2ꢀDiallyltetramethyldisilane (2a). A solution of dichloroꢀ
(ν(C=C)); 1405, 1248 (δ(CH )); 1151 (δ(SiCH)); 897
3
disilane 1a (5.0 g, 26.7 mmol) in anhydrous Et O (10 mL) was
added dropwise with vigorous stirring to a suspension of AllMgCl,
which was prepared from Mg (2.84 g, 117 mmol) and AllCl
(ν(=CH )); 832, 773, 730, 692, 643 (ν(SiC)). Raman spectrum,
2
2
∆ν/cm– : 3080 (ν(=CH)); 2952, 2897 (ν(CH)); 1630 (ν(C=C));
1
1417, 1398, 1299, 1238, 849 (ρ(CH )); 1151 (δ(SiCH)); 892
3
(
8.19 g, 107 mmol), in anhydrous Et O (30 mL). The reaction
(ν(=CH )); 743, 725, 684, 659, 642 (ν(SiC)); 478, 442, 362
2
2
mixture was brought to reflux and stirred for 10 h. Then a satuꢀ
(ν(SiSi)); 408 (δ(CC=C)).
rated NH Cl solution was added. The organic layer was sepaꢀ
1,6ꢀDiallyldodecamethylhexasilane (2e). Analogously to the
synthesis of diallyldisilane 2a, diallylhexasilane 2e was prepared
from Mg (0.64 g, 26.3 mmol), AllCl (1.84 g, 24.1 mmol), and
4
rated, washed with water to neutral pH, and dried with Na SO .
2
4
The diethyl ether was distilled off and the residue was fractionꢀ

2228
Russ.Chem.Bull., Int.Ed., Vol. 53, No. 10, October, 2004
Larkin et al.
dichlorohexasilane 1e (2.52 g, 6.0 mmol) in a yield of 1.3 g
50.4%), b.p. 133—137 °C (0.5 Torr). Found (%): C, 50.40;
3. V. F. Mironov, V. D. Sheludyakov, and V. I. Zhun´,
Zh. Obshch. Khim., 1977, 47, 1756 [J. Gen. Chem. USSR,
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Khim., 1961, 2, 563 [J. Struct. Chem. (USSR), 1961 (Engl.
Transl.)].
6. L. A. Leites, S. S. Bukalov, T. S. Yadritseva, B. A. Antipova,
and V. V. Dement´ev, Macromolecules, 1992, 25, 2991.
7. M. R. Litzow and T. R. Spalding, Mass Spectrometry of Inorꢀ
ganic and Organometallic Compounds, Ed. M. F. Lappert,
SPC, Amsterdam, 1973, 573 pp.
(
H, 10.91; Si, 38.69. C18H46Si . Calculated (%): C, 50.15;
6
1
H, 10.76; Si, 39.09. H NMR, δ: 0.28, 0.36, and 0.39 (all s,
1
4
2 H each, 12 Me); 1.81 (d, 4 H, 2 CH , J = 8.1 Hz); 5.02 (d,
2
H, 2 =CH , J = 13.7 Hz); 5.91—6.01 (m, 2 H, 2 CH). IR,
2
–
1
ν/cm : 3077 (ν(=CH)); 2953, 2891 (ν(CH)); 1634 (ν(C=C));
1
7
3
1
4
402, 1249 (δ(CH )); 1153 (δ(SiCH)); 892 (ν(=CH )); 836,
3 2
–
1
96, 768, 734, 689, 655 (ν(SiC)). Raman spectrum, ∆ν/cm
:
080 (ν(=CH)); 2958, 2893 (ν(CH)); 1632 (ν(C=C)); 1400,
300, 1253 (ρ(CH )); 1150 (δ(SiCH)); 725, 682, 660 (ν(SiC));
3
78, 360 (ν(SiSi)); 410 (δ(CC=C)).
We thank A. V. Vorontsov for recording the NMR
spectra and L. A. Mikhalitsyn for measuring the Raman
spectra.
This study was financially supported by the Russian
Foundation for Basic Research (Project No. 04ꢀ03ꢀ
8. C. H. Middlecamp, W. Wojnowski, and R. West,
J. Organomet. Chem., 1977, 140, 133.
9
. H. G. Schuster and E. Hengge, Monatsh. Chem., 1983,
14, 1305.
1
1
1
1
0. Y. Nakadaira, Y. Kobayashi, and H. Sakurai, J. Organomet.
Chem., 1973, 63, 79.
1. E. Hengge and G. Miklau, Z. Anorg. Allg. Chem., 1984,
508, 43.
2. NIST/EPA/NIH Mass Spectral Library, V. 1.0, National Inꢀ
stitute of Standards and Technology, Gaithersburg (Maryꢀ
land, USA), 2002.
3. A. I. Chernyavskii and N. A. Chernyavskaya, Izv. Akad.
Nauk, Ser. Khim., 2002, 1607 [Russ. Chem. Bull., Int. Ed.,
3
2879).
References
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1
kremniiorganicheskie polimery — polikarbosilany [Ceramicꢀ
Forming Organosilicon Polymers — Polycarbosilanes], Izdꢀvo
NIITEKhIM, Moscow, 1990, 58 pp. (in Russian).
1
2
002, 51, 1751].
2
. H. Sakurai, A. Hosomi, and M. Kumada, Tetrahedron Lett.,
1
968, 2469.
Received March 17, 2004