Synthesis of dichloro derivatives of linear and cyclic permethyloligosilanes and cyclolinear permethylpolysilane-siloxanes and permethylpolyoxysilane based on them

Article abstract of DOI:10.1023/A:1015094621119

The reactions of dodecamethylcyclohexasilane with chlorides of I, II, IV-VI, and VIII Group metals were studied as a promising approach to the synthesis of functional oligosilanes. When cyclohexasilane reacts with metal chlorides without a solvent at elevated temperatures, the process is intensified and, in some cases, the selectivity of formation of chloro derivatives of linear and cyclic permethyloligosilanes increases. The cyclolinear permethylpolysilane-siloxanes were prepared by heterofunctional polycondensation of the resulting oligosilanes with bifunctional cyclic and linear permethyloligosiloxanes. Cyclolinear permethylpolyoxysilane was synthesized for the first time by the reaction of 1,3-dihydroxycyclo-hexasilane with 1,3-dichlorohexamethyltrisilane.

Full text of DOI:10.1023/A:1015094621119

Russian Chemical Bulletin, International Edition, Vol. 51, No. 1, pp. 175—180, January, 2002
175
Synthesis of dichloro derivatives of linear and cyclic permethyloligosilanes
and cyclolinear permethylpolysilaneꢀsiloxanes and permethylpolyoxysilane
based on them
A. I. Chernyavskii, D. Yu. Larkin, and N. A. Chernyavskaya
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
The reactions of dodecamethylcyclohexasilane with chlorides of I, II, IV—VI, and
VIII Group metals were studied as a promising approach to the synthesis of functional
oligosilanes. When cyclohexasilane reacts with metal chlorides without a solvent at elevated
temperatures, the process is intensified and, in some cases, the selectivity of formation of
chloro derivatives of linear and cyclic permethyloligosilanes increases. The cyclolinear
permethylpolysilaneꢀsiloxanes were prepared by heterofunctional polycondensation of the reꢀ
sulting oligosilanes with bifunctional cyclic and linear permethyloligosiloxanes. Cyclolinear
permethylpolyoxysilane was synthesized for the first time by the reaction of 1,3ꢀdihydroxycycloꢀ
hexasilane with 1,3ꢀdichlorohexamethyltrisilane.
Key words: metal chlorides, α,ωꢀdichloropermethyloligosilanes, chloro derivatives of
cyclohexasilane, 1,3ꢀdihydroxydecamethylcyclohexasilane; heterofunctional polycondensation,
cyclolinear permethylpolysilaneꢀsiloxanes and permethylpolyoxysilane.
1
The synthesis and properties of polysiloxanes
Bifunctional linear and cyclic permethyloligoꢀ
silanes are convenient starting compounds for the prepaꢀ
ration of various copolymers containing oligosilane
fragments.
2
,3
—
—
(SiR O) — and, in recent years, polysilanes
2 n
(SiR ) —, which possess unusual chemical and physicoꢀ
2
n
chemical properties, have been well studied. Polysilaneꢀ
siloxanes of regular structure, which combine to a certain
extent the properties of two classes of organosilicon comꢀ
pounds, polysiloxanes and polysilanes, have been much
less studied. For example, the introduction of siloxane
units into polysilanes results in a higher solubility and
meltability. In addition, polysilaneꢀsiloxanes retain unꢀ
usual spectral properties (absorption in the UV region,
and the ability to undergo photochemical curing), pecuꢀ
liar in polysilanes. At particular ring size and symmetry
and polymer chain tacticity, cyclolinear permethylpolysilꢀ
The method used most widely to prepare dihaloꢀsubꢀ
stituted oligosilanes is the reaction of oligocyclosilanes
(R Si) with various halogenating agents. Thus α,ωꢀdiꢀ
2
n
chloropermethyloligosilanes Cl(Me Si) Cl (1a—d with
2
n
n = 2—4 and 6, respectively) are prepared by treatment of
dodecamethylcyclohexasilane (Me Si) (2) with chloriꢀ
4
,5
2
6,17
6
1
18
nating agents such as chlorine,
thionyl chloride,
1
9
phosphorus pentachloride, and gallium(III), tin(IV), and
2
0
titanium(IV) chlorides. Chloro derivatives of cyclohexaꢀ
silane 2 with the general formula Cl Si Me (3a—c
m
6
12–m
6
oxanes can form a mesophase. In this connection,
with m = 1—3, respectively) are prepared by chloroꢀ
demethylation of cyclosilane 2 on treatment with dry HCl
synthesis and investigation of properties of copolyꢀ
mers with the silaneꢀsiloxane structure is a topical scienꢀ
tific task.
in the presence of catalytic amounts of AlCl (chloroꢀ
3
2
1
cyclosilane 3a) or by the reaction of cyclosilane 2
To date, methods for the synthesis of linear
permethylpolysilaneꢀsiloxanes of regular structure
with SbCl5 (monochloroꢀ, dichloroꢀ, and trichloroꢀ
cyclosilanes 3a—c).
2
0,22—25
—
[(SiMe ) —O—(SiMe O) ] — (k = 2—4, 6; m = 0—3)
This study deals with the reaction of cyclohexasilane 2
with metal chlorides of various chemical natures and aims
at increasing the selectivity of the preparation of the
dichloro derivatives of linear and cyclic oligosilanes. The
prepared functional oligomers were used to synthesize
cyclolinear permethylpolyoxysilane and permethylpolyꢀ
silaneꢀsiloxanes containing linear and/or cyclic oligosilane
fragments in the polymer chain.
2
k
4
2
m n
13—15
,5,7—12
are known.
Recently,
we reported the synꢀ
thesis of cyclolinear permethyloligosilaneꢀsiloxanes based
on dichlorooligosilanes. However, a number of combinaꢀ
tions of these structural elements remained inaccessible
because of the absence of appropriate monomers, which,
in turn, is due to the inadequate selectivity of the methods
of their synthesis.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 165—169, January, 2002.
066ꢀ5285/02/5101ꢀ175 $27.00 © 2002 Plenum Publishing Corporation
1

1
76
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 1, January, 2002
Chernyavskii et al.
Results and Discussion
FeCl , TiCl , ZrCl , MoCl , WCl ) metal chlorides with
3
4
4
5
6
cyclosilane 2 in the absence of a solvent at elevated temꢀ
peratures. Under these conditions (Scheme 1, Table 1),
cyclosilane 2 reacts with the above metal chlorides with
cleavage of its Si—Si and Si—Me bonds to give linear and
cyclic chloroꢀsubstituted permethyloligosilanes.
Reactions of cyclohexasilane 2 with metal chlorides.
Previously,20 it was shown that the reaction of cyclosilane
2
1
with SnCl in CH Cl gives not only dichlorohexasilane
4 2 2
d (n = 6) as the major product but also its lower hoꢀ
mologs 1a—c (n = 2—4, respectively) formed upon cleavꢀ
7
age of the Si—Si bond in 1d. Later, it was found that the
Scheme 1
reaction of cyclosilane 2 with SnCl is accompanied by
4
not only Si—Si bond cleavage in cyclosilane 2 and
dichlorohexasilane 1d but also by cleavage of the Si—Me
bonds in the initial cyclosilane 2 to give its monochloro
(
3a) and dichloro (3b) derivatives.
n = 2 (1a), 3 (1b), 4 (1c), 6 (1d);
m = 1 (3a), 2 (3b), 3 (3c);
m > 3 (3d)
Cyclosilane 2 reacts with TiCl in CH Cl in a similar
4
2
2
way, i.e., with Si—Si and Si—Me bond cleavage in
cyclosilane 2 to give dichlorooligosilanes 1a—d and
monochlorocyclosilane 3a.
7
,20
The reaction of cyclosilane
It should be noted that tin and mercury chlorides react
with cyclosilane 2 mainly with cleavage of the Si—Si bond
giving predominantly linear dichlorooligosilanes 1a—d
(the content of chloroꢀsubstituted cyclosilanes 3a—c in
the products did not exceed 7.5%), the degree of converꢀ
sion of cyclosilane 2 being rather high (80—100%). In the
reactions of the rest of metal chlorides studied with
cyclosilane 2, the intensity of cleavage of the Si—Me
bonds in the initial ring increases, which results in markꢀ
edly higher proportions of chloroꢀsubstituted cyclosilanes
2
with tin and titanium chlorides in CH Cl proceeds
2
2
slowly with a relatively low degree of conversion of the
initial cyclic compound. Thus2 in the case of SnCl , the
degree of conversion of cyclosilane 2 after 24 h was 33%,
while in the case of TiCl , this value reached 51% after
0
4
4
0 h. It was also shown2 that in the absence of a solvent,
0
7
the degree of conversion of cyclosilane 2 in the reaction
with SnCl at 170 °C was 100% after 4 h, linear dichloroꢀ
oligosilanes 1a—d being formed as the only products.
In this respect, we studied the reaction of several
nontransition and transition (HgCl , SnCl , SbCl , CuCl ,
4
in the products. Indeed, ZrCl5 and WCl react with
cyclosilane 2 with the predominant formation of chloroꢀ
6
2
4
5
2
Table 1. Conditions and products of the reaction of cyclosilane 2 with metal chlorides MClk
b
Entry
MClk 2 : MClk T/°C
t/h
Composition of the reaction mixture (%)a
1b 1c 1d 3a 3b
Yield 1
%) sion of 2 (%)
Converꢀ
(
1
a
2
3c
1.8
1.9
1.6
0.4
4.9
1.6
2.0
19.3 d
6.3
1
2
3
4
5
6
7
8
9
HgCl2
SnCl4
SnCl4
SnCl4
SnCl4
SnCl4
1 : 2
1 : 1
1 : 1
1 : 1
1 : 2
1 : 2
1 : 1
1 : 2
1 : 1
1 : 2
1 : 1
1 : 1
1 : 1
1 : 1
1 : 1
210
175
175
175
175
175
25
2
0.5
1
2
1
33.1
7.5
45.0
13.8
2.3
2.0
0.8
1.2
86.9
86.5
87.2
89.5
78.9
86.9
0.5
66.3
53.8
33.0
53.5
55.5
27.3
40.2
34.6
98.2
82.6
86.5
89.8
99.5
100
97.2
100
60.2
10.3
19.6
81.3
80.2
78.2
94.3
11.3
14.8
19.1
34.7
37.0
—
9.6 46.1 18.1
11.3 44.3 14.2
13.5 40.2 10.9
3.9
3.4
0.9
1.8
0.8
5.4 89.3
4.5 6.8
2.1 11.2
1.6
1.4
1.5
0.8
0.4
9.0
13.5
29.9
41.5
—
25.8
18.7
—
1.5
—
0.5
3.1
0.6
—
2.8
—
2
2
c
SbCl5
SbCl5
CuCl2
CrCl3
FeCl3
TiCl4
ZrCl4
MoCl5
WCl6
25
0.002 43.4
11.4
9.6
10.8
180
210
180
175
200
185
205
1
2
2
3
2
3
1
5.8
0.1
1.4
8.0
1.9
4.6 16.1 44.3
10
11
12
13
14
15
0.3
3.6
0.4
2.3
2.6 89.7
5.7 84.3
0.2
0.3
6.7
2.4
—
—
9.2
1.9
9.3 28.4 21.2
2.2 23.4 25.7
2.2 16.4
6.4 16.2
5.3
19.0 e
9.1
10.9
17.8
6.3
9.4
4.4 17.8 27.4 14.0 10.1
5.9 6.7 6.9 7.5 4.6
11.8 f
a
b
Unidentified byꢀproducts were neglected.
Total yield of oligomers 1a—d from all reaction products (including unidentified ones) and in relation to the reacted cyclosilane 2
(
according to GLC).
The reaction was carried out in CCl4.
The reaction mixture contains 0.7% polychloroꢀsubstituted cyclosilanes 3d.
The reaction mixture contains 3.3% polychloroꢀsubstituted cyclosilanes 3d.
The reaction mixture contains 29.4% polychloroꢀsubstituted cyclosilanes 3d.
c
d
e
f

Synthesis of dichloropermethyloligosilanes
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 1, January, 2002
177
substituted cyclosilanes 3a—c; polychlorinated cycloꢀ
certain extent the length of the oligomer chain in the
resulting α,ωꢀdichlorooligosilanes 1.
silanes Cl Si Me (3d, m > 3) are also formed. For
m
6
12–m
example, CrCl and FeCl proved to be the poorest chloꢀ
Synthesis of cyclolinear polysilaneꢀsiloxanes and polyꢀ
oxysilane. Based on synthesized oligosilanes, studies on
the preparation of new polymers and copolymers conꢀ
taining oligosilane structural fragments were continued.
New cyclolinear permethylpolysilaneꢀsiloxanes were preꢀ
pared by heterofunctional polycondensation of linear 1c
and cyclic 3b dichlorooligosilanes with cyclic 4 and linꢀ
ear 5 dihydroxyoligosiloxanes, respectively (Scheme 2).
Dichloroꢀsubstituted cyclosilane 3b was used as a mixꢀ
ture of structural and spatial isomers (dichlorocycloꢀ
silanes 3b´ and 3b″ in ∼ 1 : 1 ratio, see Experimental),
and dihydroxycyclosiloxane 4, as a mixture of cisꢀ and
transꢀisomers (∼ 2 : 3).
3
3
rinating agents for cyclosilane 2; the degree of conversion
of 2 was ≤20%; however, even in those cases where the
conversion of cyclosilane 2 in the reactions with metal
chlorides was rather high, the yield of linear dichloroꢀ
oligosilanes 1a—d did not exceed 55%.
Previously, it was shown2 that the reaction of SbCl5
0
with cyclosilane 2 in the presence of a solvent (CH Cl ,
2
2
CHCl , CCl ) proceeds selectively with cleavage of only
3
4
Si—Me bonds in the initial cyclosilane 2, the Si—Si bonds
remaining intact. When reproducing the procedure, we
obtained almost analogous results (see Table 1, entry 7),
namely, the content of the linear dichlorooligosilane 1d
in the reaction mixture was only 0.5%. Dichloroꢀsubstiꢀ
tuted cyclosilane 3b was formed as the major reaction
product; as shown previously,2
2—24
Scheme 2
this product was a
mixture of structural isomers, namely, 1,3ꢀdichloroꢀ
cyclosilane (3b´) and 1,4ꢀdichlorocyclosilane (3b″) (in
∼
1 : 1 ratio), which are, in turn, mixtures of cisꢀ and
2
9
transꢀisomers (see Experimental, Si NMR spectra of
cyclosilanes 3b´ and 3b″). A very reactive chlorinating
agent for cyclosilane 2 is SbCl . Treatment of cyclosilane
5
2
with SbCl in a 1 : 2 ratio at ∼ 20 °C without a solvent
5
bring about a vigorous exothermal reaction with 100%
conversion of cyclosilane 2 over a period of several secꢀ
onds; this gives not only chloroꢀsubstituted cyclosilanes
3
a—d but also linear α,ωꢀdichlorooligosilanes 1a—d (the
ratio of linear to cyclic chloroꢀsubstituted oligosilanes
was ∼ 2 : 1). Thus, unlike the reaction in solutions, not
only Si—Me but also Si—Si bonds of cyclosilane 2 are
cleaved in the solventꢀfree reaction.
The influence of the reaction conditions on the conꢀ
version of cyclosilane 2, on the yield and composition of
the reaction products, and on the ratio between them was
studied in relation to the reaction of 2 with SnCl . An
4
increase in the reaction time (cf. entries 2—4, 5, and 6 in
Table 1) results in a higher yield of linear dichloroꢀ
oligosilanes 1a—d and a lower content of chloroꢀsubstiꢀ
tuted cyclosilanes 3a—c in the reaction products. In addiꢀ
tion, the content of shortꢀchain linear oligomers 1a and
1
b increases and the content of dichlorotetrasilane 1c and
dichlorohexasilane 1d decreases. Evidently, this is due to
an increase in the intensity of Si—Si bond cleavage in
oligomers 1c and 1d following an increase in the reaction
time. For equal reaction times, transition from 1 : 1 ratio
The reactions were carried out in the presence of Py as
an HCl acceptor. The yield of copolymers 6a,b was
80—94%. The molecular masses of copolymers 6a and 6b
estimated from viscometry data were ∼ 6000 and ∼ 11000,
respectively. Heterofunctional polycondensation of
1,3ꢀdihydroxydecamethylcyclohexasilane (7), prepared by
hydrolysis of a mixture of dichlorocyclosilane isomers 3b´
and 3b″ using modification of a reported method, with
1,3ꢀdichlorotrisilane 1b by a similar procedure gave
cyclolinear permethylpolyoxysilane (8), whose backbone
consisted of cyclic and linear silane fragments linked by
of cyclosilane 2 to SnCl to 1 : 2 ratio (cf. entries 3 with 5
4
and 4 with 6 in Table 1), allows one to attain virtually
1
00% conversion of cyclosilane 2 with simultaneous sharp
decrease (to 0—1.5%) in the content of dichlorohexasilane
d in the reaction products. In addition, the content of
2
4
1
shortꢀchain oligomers 1a and 1b increases 2—3ꢀfold.
Thus, variation of conditions of the reaction between
cyclosilane 2 and SnCl makes it possible to control to a
4

1
78
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 1, January, 2002
Chernyavskii et al.
oxygen bridges, the product yield being 74% (Scheme 3).
equal to –97 °C. This low T value of copolymer 8 is,
g
The weight average molecular mass M of copolymer 8
apparently, due to the presence of oxygen bridges beꢀ
tween cyclic and linear silane fragments in the copolymer
backbone.
w
was 4670; polydispersity M /M = 1.48.
w
n
Thus, new cyclolinear permethylpolysilaneꢀsiloxanes
and permethylpolyoxysilane of a regular structure were
synthesized by heterofunctional polycondensation.
Scheme 3
Experimental
GLC analysis was carried out on a LKhMꢀ8MD chromatoꢀ
graph (a 0.3×100 cm stainlessꢀsteel column, 5% SEꢀ30 on
Chromaton NꢀAWꢀDMCS; katharometer as the detector,
temperature programming from 30 to 300 °C, heating rate
–
1
1
2 K min ; helium as the carrier gas).
29Si NMR spectra were recorded on Bruker WPꢀ200 SY
(
39.76 MHz) and Bruker WPꢀ400 SY (79.46 MHz) spectromꢀ
eters using Me Si as the internal standard. IR and UV spectra
4
were recorded in thin films using Specord Mꢀ82 and Specord
Mꢀ40 spectrophotometers, respectively.
The intrinsic viscosity [η] of polysilaneꢀsiloxanes 6a,b was
determined in toluene at 25 °C using a Ubbelohde viscomꢀ
eter with suspended level. The molecular masses of copolyꢀ
mers 6a,b were roughly estimated using coefficients of the
Mark—Kuhn—Houwink equation for cyclolinear polysiloxanes
Copolymers 6a,b and 8 are thick colorless liquids
readily soluble in conventional organic solvents. The synꢀ
thesized copolymers were characterized by IR, UV, and
NMR spectroscopy. The 2 Si NMR spectra (see Experiꢀ
mental) confirm the formation of regular copolymers with
the backbone consisting of alternating cyclic and linear
fragments. The IR spectra of copolymers 6a,b and 8 exꢀ
hibit absorption bands in the region of ν 1070 and
2
8
reported previously.
The molecularꢀmass characteristics of copolymer 8 were
determined by gel chromatography on a Bruker LC21 liquid
chromatograph (refractometer as the detector, columns with
the polystyreneꢀdivinylbenzene gel, toluene as the eluent, caliꢀ
bration against the polystyrene standard).
9
Cyclosilane 2 was prepared by catalytic depolymerization
7
–1
of polydimethylsilane by a procedure described previously.
1
040—1025 cm , typical of the Si—O—Si bond. Owing
Monoꢀ and trichloroꢀsubstituted cyclosilanes 3a,c were identiꢀ
to the presence of oligosilane fragments in the polymer
chain, copolymers 6a,b and 8 retain the ability to absorb
in the UV region inherent in compounds with a purely
silane structure. Indeed, the UV spectrum of copolymer
fied by comparison with reference samples synthesized by known
2
1,25
procedures.
1,3ꢀDihydroxycyclosilane 7 was prepared by a
24
modification of a published procedure. Dihydroxycyclosiloxane
4
(a mixture of cisꢀ and transꢀisomers in ∼ 2 : 3 ratio) was syntheꢀ
6
a exhibits an absorption band at about 235 nm, whose
sized by a known procedure.29 Dihydroxydisiloxane 5 was preꢀ
pared by a known procedure.30 Immediately prior to the use,
TiCl4, SnCl4, and SbCl5 were distilled in an N2 flow, while the
other metal chlorides were used as received. Ether and benzene
were dried by refluxing followed by distillation over sodium
metal in the presence of benzophenone in an N flow; CCl and
position virtually coincides with that for the initial
dichlorotetrasilane 1c (234 nm). The UV absorption of
copolymer 6b is due to the presence of cyclosilane fragꢀ
ments in the polymer chain (two absorption bands in the
region of 256 and 273 nm). The UV spectrum of copolyꢀ
mer 8 exhibits one absorption band at about 280 nm,
typical of the cyclohexasilane unit present in the copolyꢀ
mer, while the absorption band corresponding to the linꢀ
ear oligosilane fragment in the polymer structure is missꢀ
ing. A similar pattern (the presence of absorption bands
due to cyclic fragments and the absence of bands for the
linear fragments) was observed in the UV spectra of
cyclolinear compounds with the purely silane structure,
2
4
MeCN were dried by distillation over P O in an N flow. Pyriꢀ
2
5
2
dine was distilled over NaOH granules. All the reactions were
carried out in an atmosphere of dry argon or nitrogen.
Reaction of cyclosilane 2 with SnCl4 (typical procedure)
(Table 1, entry 3). Cyclosilane 2 (34.9 g, 0.1 mol) was placed in
an ampoule equipped with a branch for reactant introduction
and a Teflon stopcock, SnCl4 (26.1 g, 0.1 mol) was added, and
the ampoule was placed in an oil bath preꢀheated to 175 °C. The
reaction mixture was kept at this temperature with intense stirꢀ
ring for 1 h. The ampoule was cooled and 50 mL of anhydrous
CCl4 was added. The SnCl2 precipitate was filtered off and
2
6
α,ωꢀbis(cyclopentasilanyl)oligodimethylsilanes.
The glass transition temperature T of copolymer 8
g
washed with anhydrous CCl (2×10 mL). The solvent was evapoꢀ
4
was –100 °C, which is close to the calculated* T value
g
rated and the residue was analyzed by GLC (see Table 1). Fracꢀ
tionation of the residue gave 5.6 g (10.0% relative to the reacted
cyclosilane 2) of dichlorodisilane 1a, b.p. 148—148.5 °C,
*
The T value for copolymer 8 was calculated by Prof. A. A.
g
2
7
29
Askadskii by the atomic constants method.
Si NMR (CCl ), δ: 17.21; 8.1 g (16.5%) of dichlorotrisilane
4

Synthesis of dichloropermethyloligosilanes
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 1, January, 2002
179
1
b, b.p. 84—85 °C (10 Torr), 29Si NMR (CCl ), δ: 24.98
lar to the previous one gave 4.19 g (80%) of polysilaneꢀsiloxane
4
(
SiMe Cl), –43.71 (SiMe ); and 5.7 g (12.7%) of dichlorotetraꢀ
6b. Fractional precipitation gave the fraction (1.85 g) of copolyꢀ
mer 6b, [η] = 0.08 dl g , molecular mass ∼ 11000. Found (%):
2
2
2
9
–1
silane 1c, b.p. 111—113 °C (5 Torr), Si NMR (CCl ), δ: 26.26
4
(
SiMe Cl), –42.68 (SiMe ). After evaporation of lower dichloroꢀ
C, 34.47; H, 8.27; Si, 46.08. C H O Si . Calculated (%):
2
2
14 42
3
8
oligosilanes 1a—c, the initial cyclosilane 2 and chloroꢀsubstiꢀ
tuted cyclosilanes 3a and 3b were removed by sublimation. Disꢀ
tillation of the residue gave 20.8 g (49.5%) of dichlorohexasilane
C, 34.85; H, 8.71; Si, 46.47. UV, λmax/nm: 256, 273. IR (KBr),
–
1
ν/cm : 2953, 2885 (C—H); 1261, 841, 802, 764 (Si—Me);
2
9
1074, 1025 (SiOSi). Si NMR (CDCl ), δ: 5.52, 5.04,
3
2
9
1
d, b.p. 166—167 °C (1 Torr), m.p. 45—46 °C. Si NMR (CCl ),
((Si) SiO), 5.42, 4.96 (OSiSiSiO), –20.59, –21.07, –21.22,
4
2
δ: 26.35 (SiMe Cl); –40.90 (Si Me ); –39.65 (Si Me ).
–21.39 (OSiOSiO), –43.12, –44.16 (OSi(Si) SiO), –43.28,
2
b
2
c
2
2
Entries 1, 2, 4—6, and 8—15 were carried out in a similar
way (entry 8, without heating) (see Table 1) except that the
–43.35, –44.62, –44.75 (OSiSiSi, OSiSiSiO), –47.03, –47.54
(OSiSiSiSiSiO).
residue after removal of CCl was not fractionated but was anaꢀ
lyzed by GLC.
The reaction of dihydroxycyclosilane 7 (1.18 g, 3.35 mmol),
dichlorotrisilane 1b (0.82 g, 3.35 mmol), and Py (0.53 g,
6.70 mmol) carried out similarly to the synthesis of copolymer 6a
gave 1.30 g (74.3%) of polyoxysilane 8. Reprecipitation gave a
fraction (0.73 g) with [η] = 0.10 dl g– , M = 4670, M = 3160.
4
Reaction of cyclosilane 2 with SbCl5 (Table 1, entry 7).
A solution of SbCl (11.8 g, 39.4 mmol) in 30 mL of anhydrous
5
1
CCl was added dropwise to a solution of cyclosilane 2 (10.0 g,
4
w
n
2
8.7 mmol) in 55 mL of anhydrous CCl cooled to 0 °C. The
Found (%): C, 36.21; H, 9.05; Si, 47.85. C H O Si . Calcuꢀ
16 48 2 9
4
reaction mixture was vigorously stirred for 2 h at ∼ 20 °C, the
course of the reaction being monitored by GLC. The precipitate
was filtered off and washed with anhydrous hexane (2×10 mL).
The solvents were removed on a rotary evaporator and the initial
cyclosilane 2 and the reaction products (chloroꢀsubstituted
cyclosilanes 3a—c) were extracted from the residue with anhyꢀ
drous hexane (3×10 mL). Acetonitrile (6 mL) was added to the
resulting solution for deactivation of antimony compounds and
the hexane solution of the reaction products was separated using
a separating funnel. Hexane was removed on a rotary evaporaꢀ
tor. The initial cyclosilane 2 and monochloroꢀsubstituted
cyclosilane 3a were removed from the crystalline residue by
sublimation (80 °C, 1 Torr). The residue after sublimation was
recrystallized from anhydrous pentane to give 6.7 g (60%) of a
mixture of 1,3ꢀ (3b´) and 1,4ꢀdichlorocyclosilane (3b″) isoꢀ
mers (∼ 1 : 1). 29Si NMR (CCl4 : CDCl3 (1 : 1)), δ: 3b´
lated (%): C, 36.58; H, 9.21; Si, 48.12. UV, λmax/nm: 280.
IR (KBr), ν/cm– : 2953, 2891 (C—H); 1249, 836, 802, 768
(Si—Me); 1028 (SiOSi). 2 Si NMR (CDCl ), δ: 8.80 ((Si) SiOSi);
1
9
3
5
6.98
((Si) SiOSiSiSiO);
–42.79
(O(Si)SiSiSi(Si)O);
5
–43.50 (OSiSiSiSiSiO); –48.00 (OSiSiSiSiSiO); –53.04
((Si) SiOSiSiSiO).
5
The authors are grateful to A. Z. Kreidlin for particiꢀ
pation in the discussion and valuable remarks.
This work was financially supported by the Russian
Foundation for Basic Research (Projects Nos. 00ꢀ03ꢀ
3
3189 and 01ꢀ03ꢀ06231).
References
(
(
–
1
cisꢀ, transꢀisomers): 15.42, 14.90 (SiMeCl), –37.05, –37.62
1. A. A. Zhdanov and M. M. Levitsky, in Uspekhi v oblasti
sinteza elementoorganicheskikh polimerov [Advances in the
Synthesis of Organometallic Polymers], Nauka, Moscow, 1988,
192 (in Russian).
ClSiSiMe SiCl), –38.94, –39.36 (Me SiSiMe SiCl), –42.48,
2
2
2
44.59 (Me SiSiMe SiMe ); 3b″ (cisꢀ, transꢀisomers): 15.60,
2 2 2
5.13 (SiMeCl), –39.66, –39.92 (SiMe ).
2
Synthesis of polysilaneꢀsiloxanes 6a,b and polyoxysilane 8.
2. R. West, J. Organomet. Chem., 1986, 300, 327.
3. R. D. Miller and J. Michl, Chem. Rev., 1989, 89, 1359.
4. J. Chojnowski, J. Kurjata, S. Rubinsztajn, and M. Scibiorek,
in Frontiers of Organosilicon Chemistry. Eds. A. R. Bassindale
and P. P. Gaspar, The Royal Society of Chemistry, Camꢀ
bridge, 1991, 70.
5. J. Chojnowski, J. Kurjata, and S. Rubinsztajn, Makromol.
Chem., Rapid Commun., 1988, 9, 469.
6. N. N. Makarova and Yu. K. Godovsky, Prog. Polym. Sci.,
1997, 22, 1001.
7. A. I. Chernyavskii and B. G. Zavin, Izv. Akad. Nauk, Ser.
Khim., 1997, 1513 [Russ. Chem. Bull., 1997, 46, 1449 (Engl.
Transl.)].
A mixture of dihydroxycyclosiloxane 4 (0.7 g, 1.56 mmol) and
Py (0.24 g, 3.12 mmol) in 5 mL of anhydrous ether was added
dropwise to a solution of dichlorotetrasilane (0.47 g, 1.56 mmol)
´
1
c in 1 mL of anhydrous ether with intense stirring. The reaction
mixture was stirred for 8 h at ∼ 25 °C, 2.5 mL of anhydrous
benzene was added, and the mixture was brought to boiling and
stirred for 20 h. Anhydrous benzene (15 mL) was added and the
Py•HCl precipitate was filtered off and washed with anhydrous
benzene (2×5 mL). The benzene solution was washed with waꢀ
ter to a neutral reaction and dried with Na SO . The polymer
2
4
was precipitated by adding a threefold excess of MeOH and
dried in a vacuum chamber (60 °C) to a constant weight to give
1
1
.0 g (94.3%) of polysilaneꢀsiloxane 6a, [η] = 0.05 dl g– , moꢀ
8. J. Chojnowski, W. Fortuniak, N. Gladkova, M. Pluta,
´
lecular mass ∼ 6000. Found (%): C, 31.47; H, 7.97; Si, 40.98.
M. Scibiorek, and B. Zavin, J. Inorg. Organomet. Polym.,
C H O Si . Calculated (%): C, 31.86; H, 7.96; Si, 41.40.
UV, λmax/nm: 235. IR (KBr), ν/cm : 2958, 2913, 2879
1995, 5, 7.
18
54
8
10
–
1
9. M. Kumada and K. Tamao, Adv. Organomet. Chem.,
(
2
C—H); 1260, 853, 802, 762 (Si—Me); 1075, 1040 (SiOSi).
1968, 9, 19.
9
Si NMR (CCl : CDCl (1 : 1)), δ: 9.41, 8.73 ((—O) SiOSiSi),
10. J. Kurjata and J. Chojnowski, Makromol. Chem., 1993,
4
3
2
–
21.61, –22.10, –22.35, –22.78 (OSiOSiO), –47.67, –48.79
194, 3271.
(
OSi(Si) SiO), –64.65, –65.75 ((—O) SiOSiSi).
11. J. Chojnowski and J. Kurjata, Macromolecules, 1994,
27, 2302.
12. J. Chojnowski, J. Kuriata, S. Rubinsztajn, M. Scibiorek, and
2
2
The reaction of isomer mixture of dichlorocyclosilanes 3b´
and 3b″ (4.22 g, 10.87 mmol), dihydroxydisiloxane 5 (1.80 g,
0.87 mmol), and Py (1.72 g, 21.74 mmol) by a procedure simiꢀ
´
1
M. Zeldin, J. Inorg. Organomet. Polym., 1992, 2, 387.

1
80
Russ.Chem.Bull., Int.Ed., Vol. 51, No. 1, January, 2002
Chernyavskii et al.
1
1
3. N. A. Chernyavskaya, V. I. Aleksinskaya, and A. I.
Chernyavskii, Izv. Akad. Nauk, Ser. Khim., 1998, 544 [Russ.
Chem. Bull., 1998, 47, 526 (Engl. Transl.)].
4. A. I. Chernyavskii, A. I. Belokon´, N. A. Chernyavskaya,
V. I. Aleksinskaya, B. G. Zavin, and Yu. S. Nekrasov, Izv.
Akad. Nauk, Ser. Khim., 1999, 1729 [Russ. Chem. Bull., 1999,
23. E. Hengge and M. Eibl, J. Organomet. Chem., 1992, 428, 335.
24. A. Spielberger, P. Gspaltl, H. Siegl, E. Hengge, and
K. Gruber, J. Organomet. Chem., 1995, 499, 241.
25. M. Eibl, U. Katzenbeisser, and E. Hengge, J. Organomet.
Chem., 1993, 444, 29.
26. E. Hengge and P. K. Jenkner, Z. Anorg. Allg. Chem., 1988,
560, 27.
4
8, 1707 (Engl. Transl.)].
1
1
1
1
5. A. I. Chernyavskii, N. A. Chernyavskaya, V. I. Aleksinskaya,
and B. G. Zavin, J. Organomet. Chem., 1999, 579, 328.
6. P. K. Sen, D. Ballard, and H. Gilman, J. Organomet. Chem.,
27. A. A. Askadskii and V. I. Kondrashchenko, Komp'yuternoe
materialovedenie polimerov [Computer Materials Science of
Polymers], Nauchnyi Mir, Moscow, 1999, 1, 544 pp. (in
Russian).
28. N. N. Makarova, I. I. Mamaeva, and I. M. Petrova, Vysokoꢀ
molekulyarn. Soedinen., Ser. A, 1987, 29, 1507 [Polym. Sci.
USSR, Ser. A, 1987, 29 (Engl. Transl.)].
29. N. N. Makarova, I. M. Petrova, Yu. K. Godovsky, B. D.
Lavrukhin, and A. A. Zhdanov, Dokl. Akad. Nauk SSSR,
1983, 269, 1368 [Dokl. Chem., 1983 (Engl. Transl.)].
30. C. K. Lucas and R. W. Martin, J. Am. Chem. Soc., 1952,
74, 5225.
1
968, 15, 237.
7. W. Wojnowski, C. J. Hurt, and R. West, J. Organomet. Chem.,
977, 124, 271.
1
8. P. K. Jenkner, A. Spielberger, and E. Hengge, J. Organomet.
Chem., 1992, 427, 161.
9. H. Gilman and S. Inoue, J. Org. Chem., 1964, 29, 3418.
0. B. Derczewski and W. Wojnowski, J. Prakt. Chem., 1990,
1
2
3
32, 229.
1. M. Ishikawa and M. Kumada, Synth. Inorg. Met.ꢀOrg. Chem.,
971, 1, 191.
2. F. K. Mitter and E. Hengge, J. Organomet. Chem., 1987,
32, 47.
2
2
1
Received October 19, 2000;
in revised form June 28, 2001
3