REACTIONS OF (TRIETHYLSTANNYLTHIOALKYL)TRIALKOXYSILANES
2059
methyl)sulfonium iodide VI were filtered off through a
glass frit, washed on the filter with dry ether, and dried
in a vacuum. Yield 0.3 g. From the filtrate after
evaporation and fractional distillation of the residue in
dropwise, the reaction mixture was stirred for another
2 h and left overnight. The precipitate formed was
filtered off, washed with ether (3×3 ml), and dried in a
vacuum to give 1.8 g (93%) of 1-(methylthiomethyl)
silatrane IX. Colorless fine-crystalline powder, mp
133–135°С {[2]: mp 135°С}. From ether extracts after
removal of ether and fractional distillation of the
residue in a vacuum 1.9 g of iodotriethylstannane was
a vacuum 2.2 g of Et SnI and 1.5 g of (methyl-
3
thiomethyl)-trimethoxysilane IV was isolated.
Reaction of (2-triethylstannylthioethyl)trimeth-
oxysilane (I) with methyl iodide. a. (molar ratio of
the reagents ~1:1). To the solution of 3.8 g of (2-tri-
ethylstannylthioethyl)-trimethoxysilane in 2.5 ml of
chloroform 1.4 g of MeI was added. The reaction
mixture was kept for 10 h at room temperature, the
solution was evaporated in a vacuum, the precipitated
crystals of dimethyl(2-trimethoxysilylethyl)sulfonium
iodide VII were separated, washed on a glass frit filter
with dry ether, and dried in a vacuum. Yield 0.7 g.
Colorless crystals, mp 89–90°С. Found, %: С 24.37, Н
2
0
isolated, bp 97–99°С (10 mm Hg), n 1.5645 {[14]:
D
1
8
bp 105.5–106 (16 mm Hg), n 1.5653}.
D
b. (molar ratio of the reagents ≥ 1:3). To the stirred
solution of 8.5 g of silatrane VIII in 30 ml of ether the
solution of 5 g of MeI in 10 ml of ether was added
dropwise, the mixture was refluxed for 0.5 h, cooled to
room temperature, and kept in the dark during 6 h. The
precipitate formed was filtered off, washed with ether,
and dried in a vacuum to afford 7.2 g (96%) of dimethyl-
(silatranylmethyl)sulfonium iodide X. Colorless fine-
crystalline powder, mp 208–209°С {[6]: 210–212°С}.
From ether solution 5.5 g of iodotriethylstannane was
isolated.
5
2
.17, S 9.05, Si 7.94. С H IO SSi. Calculated, %: С
4.85, Н 5.66, S 9.48, Si 8.30. H NMR spectrum, δ,
7 19 3
1
ppm: 1.18 m (2Н, СН Si), 3.35 s (6Н, 2СН ), 3.62 s
2
3
1
3
(
9Н, 3 ОСН ), 3.77 m (2Н, SCH ). С NMR spec-
3 2
trum, δ, ppm: 5.25 (C–Si), 25.09 (СН ), 39.26 (SCH ),
3
2
Reaction of 1-(2-triethylstannylthioethyl)silatrane
XI) with methyl iodide. a. (molar ratio of the
reagents ~1:1). To the stirred solution of 4.4 g of
silatrane XI in 10 ml of ether the solution of 1.5 g of
MeI in 3 ml of ether was added dropwise, the reaction
mixture was stirred for 1.5 h and kept in the dark for
2
9
5
1.00 (ОСН3). Si NMR spectrum, δ, ppm: –49.04.
From the filtrate by fractional distillation in a vacuum
.0 g of triethyliodostannane III and 1.5 g of (2-
methylthioethyl)trimethoxysilane V with bp 55–57°С
(
1
2
0
1
(
1.5 mm Hg), nD 1.4480 was isolated. Н NMR
spectrum, δ, ppm: 0.99 m (2Н, СН Si), 2.09 s (6Н,
2
6
h. The precipitate formed after evaporation of ether
1
3
2
СН ), 3.57 s (9Н, 3 ОСН ), 2.58 m (2Н, SCH ). С
o
3
3
2
was separated, washed with ether cooled to –10 C, and
dried in a vacuum to give 2.2 g (88%) of 1-(2-me-
thylthioethyl)silatrane II. Colorless fine-crystalline
NMR spectrum, δ, ppm: 10.40 (C–Si), 15.30 (СН ),
3
2
9
2
8.35 (SCH ), 50.64 (ОСН ). Si NMR spectrum, δ,
2 3
ppm: –44.81.
1
powder, mp 122–124°С {[3]: mp 125–126°С}. Н
b. (molar ratio of the reagents ~1:3). To the
NMR spectrum, δ, ppm (CDCl ): 0.76 m (2Н, СН Si),
3
2
solution of 4.0 g of (2-triethylstannylthioethyl)-tri-
2.07 s (3Н, Ме), 2.64 m (2Н, SCH ), 2.81 t (6Н,
2
methoxysilane in 3 ml of CHCl 4.2 g MeI was added
NCH ), 3.76 t (6Н, ОCH ).
3
2
2
dropwise keeping the temperature of the reaction
mixture at ~20°С. The mixture was left overnight in a
refrigerator. The precipitated crystals of dimethyl(2-
trimethoxysilylethyl)sulfonium iodide VII were sepa-
rated, washed on the glass frit filter with dry ether, and
dried in a vacuum. Yield 2.9 g. From the filtrate after
evaporation and fractional distillation in a vacuum 2.5 g
b. (molar ratio of the reagents ≥ 1:3). 4.5 g of
silatrane XI was dissolved in 10 ml of the mixture
(
1:1) of ether and chloroform, and 4.5 g of MeI was
added at stirring. The mixture was stirred for 1.5 h at
room temperature and 3 h at reflux, then cooled to
room temperature and kept for 6 h in the refrigerator.
The precipitate formed was separated, washed with
ether, and dried in a vacuum to give 0.7 g of
trimethylsulfonium iodide, mp 207–210°С (decomp.)
2
0
of fraction with bp 97–100°С (10 mm Hg), n 1.5260
D
was isolated, consisting mainly of Et SnI and a small
3
amount of (2-methylthioethyl)trimethoxysilane V.
{
[15]: mp 208–213°С (decomp.)}. From the filtrate the
Reaction of (triethylstannylthiomethyl)silatrane
solvent was removed, the residue sublimed in a
(
VIII) with methyl iodide. a. (molar ratio of the
vacuum to give 1.3 g of 1-ethoxysilatrane, mp 98–100°
1
reagents ~1:1). To the stirred solution of 3.5 g of
silatrane VIII in 10 ml of ether at room temperature
the solution of 1.2 g of MeI in 5 ml of ether was added
С. Н NMR spectrum, δ, ppm (CDCl ): 1.18 t (3Н,
3
Ме), 2.83 t (6Н, 3NCH ), 3.71 t (2Н, СН ), 3.82 t (6Н,
2
2
3ОСН ). Mass spectrum, m/z: 32, 45, 55, 63, 71, 89,
2
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 78 No. 11 2008