Synthesis and properties of ionic liquids with siloxane-functionalized cations

Article abstract of DOI:10.1007/s11172-014-0802-5

Four novel ionic liquids with siloxane-functionalized cations were synthesized and characterized. Their thermal stability was studied by the TG method; glass transition points, viscosities, and densities were also measured.

Full text of DOI:10.1007/s11172-014-0802-5

Russian Chemical Bulletin, International Edition, Vol. 63, No. 12, pp. 2702—2706, December, 2014
2702
Synthesis and properties of ionic liquids with siloxaneꢀfunctionalized cations
E. A. Chernikova,a L. M. Glukhov,a V. G. Krasovskiy,a L. M. Kustov,a,b and A. A. Koroteevc
aN. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences,
47 Leninsky prosp., 119991 Moscow, Russian Federation.
Fax: +7 (499) 137 2935. Eꢀmail: lmk@ioc.ac.ru
bDepartment of Chemistry, M. V. Lomonosov Moscow State University,
1 Leninskie Gory, 119992 Moscow, Russian Federation
cMoscow Aviation Institute,
4 Volokolamskoe shosse, 125993 Moscow, Russian Federation
Four novel ionic liquids with siloxaneꢀfunctionalized cations were synthesized and characꢀ
terized. Their thermal stability was studied by the TG method; glass transition points, viscosiꢀ
ties, and densities were also measured.
Key words: ionic liquids, organosilicon compounds, siloxanes, bis(trifluoromethylꢀ
sulfonyl)imides, heatꢀtransfer fluid.
The last decade has seen a substantial increase in apꢀ
plications of ionic liquids (ILs). At present, ~2000 indiꢀ
vidual compounds were synthesized,1 but only a small fracꢀ
tion of these compounds was more or less completely charꢀ
acterized by physicochemical methods. Many ILs have
such thermophysical parameters that make it possible to
consider them as candidates for heatꢀtransfer fluids. The
development of novel heatꢀtransfer fluids based on ILs
includes the search for possibilities of improving their therꢀ
mal stability and, in particular, operation temperature.
Careful studies suggested substituted imidazolium and pyrꢀ
rolidinium bis(trifluoromethylsulfonyl)imides (Tf2N–) as
the most promising ILs.
Because of the ionic character of the liquid state, ILs
show a negligently low saturated vapor pressure at high
temperatures (<10–3 Torr at temperatures higher
than 200 С).2 Due to this feature, ILs are nonꢀvolatile
and explosion safe and for this reason are especially
attractive as heatꢀtransfer fluids for the operation unꢀ
der conditions of dynamic vacuum and, possibly, in an
outer space.
Novel ionic liquids intended for use as heatꢀtransfer
fluids should possess higher thermal stability, in particular,
enhanced operation temperatures, and have minimal corꢀ
rosivity to metals and construction alloys. A possible
approach to meet these problems is the synthesis of organoꢀ
silicon ILs by the introduction of various ionic nitrogenꢀ
containing fragments into lowꢀmolecularꢀweight organoꢀ
siloxanes.
Monoꢀ and dicationic quaternary ammonium salts
containing the organosilicon fragment are described in
detail so far. Among these are products of quaternization of
tertiary amines (cyclic3—5 and acyclic3,6—8), pyridine,9—12
and imidazole13—15 with various haloꢀ and di(haloalkyl)ꢀ
siloxanes. The most compounds were synthesized as haꢀ
lides and were characterized only by spectroscopic methods.
Their physicochemical properties were scarcely studied.
Among possible applications of the synthesized salts, their
use as surfactants, antiꢀfoaming agents, additives to oils
and polymers, dressings for glass fibers, and lubricants is
considered.16 The salts containing two nitrogen atoms,
disiloxane fragment, and long substituents in the cation
were patented as templates for the synthesis of mesopoꢀ
rous materials.17
There are only few works on the synthesis of siloxaneꢀ
functionalized ILs (salts with m.p. < 100 С) with nonꢀ
halide anions.6,13—15 Bis(trifluoromethylsulfonyl)imides
and bis(oxalato)borates of tetraalkylammonium cations
with the pentamethyldisiloxane fragment were described.6
The synthesized salts have low glass transition temperaꢀ
–
–
tures ( 30—( 60) С) and can be used as electrolytes.
Imidazolium and pyrrolidinium ILs with pentamethyldiꢀ
siloxane and branched heptamethyltrisiloxane fragments
in the cation were synthesized.13—15 Anions Tf2N– and
Al[OCH(CF3)2]4– were used14 as counterions. All syntheꢀ
sized compounds were characterized by spectroscopic
methods, and their viscosities and electric conductivities
were measured at different temperatures.
In addition to the suitable thermophysical characterisꢀ
tics, IL should possess a certain combination of physicoꢀ
chemical properties as a heatꢀtransfer fluid for use under
dynamic vacuum conditions. Among these properties, the
saturated vapor pressure, thermal stability, viscosity, and
melting points are the most important ones.
This work describes the synthesis and study of the physꢀ
icochemical properties of ILs with siloxaneꢀfunctionalꢀ
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2702—2706, December, 2014.
1066ꢀ5285/14/6312ꢀ2702 © 2014 Springer Science+Business Media, Inc.

Siloxaneꢀfunctionalized ionic liquids
Russ.Chem.Bull., Int.Ed., Vol. 63, No. 12, December, 2014 2703
ized cation and the evaluation of prospects of their appliꢀ
cation as heatꢀtransfer fluids.
replacement of the solvent by 1,2ꢀdimethoxyethane reꢀ
sulted in an increase in the solvation of Na+, which subꢀ
stantially accelerated the process. Sodium dimethylꢀ
phenylsilanolate (1a) was also synthesized in 1,2ꢀdimethꢀ
oxyethane.
Results and Discussion
The reaction of silanolates 1a,b with chloromethyldiꢀ
methylchlorosilane is exothermic and proceeds rather selecꢀ
tively at 10—15 С. However, the selectivity decreases with
an increase in the local or bulk temperature of the reaction
mixture, which affords the disubstitution product. The isoꢀ
lation of compounds 2a,b with purity higher than 99%
(GLC) in a high yield is attained by vacuum fractionation
using a 80 cm Vigreaux column.
Siloxaneꢀfunctionalized 1,2ꢀdimethylimidazolium,
1ꢀmethylpyrrolidinium, and trimethyammonium bis(triꢀ
fluoromethylsulfonyl)imides with one or two phenyl groups
in the disiloxane fragment were chosen as the objects of
the present study. The synthesis of each IL includes four
steps. The first two steps (synthesis of chloromethylorganoꢀ
disiloxane) are generalized in Scheme 1.
The addition of chloromethylorganodisiloxanes 2a,b
to amines followed by ion exchange is shown in Scheme 2.
Both processes are extensively studied,19—21 and they are
carried out using standard procedures with a high yield of
the salts at each step.
Scheme 1
All synthesized ILs with the Tf2N– anions are liquid at
room temperature. No crystallization was observed for
compounds 6a,b, 7, and 8 on cooling under the DSC
conditions or in a bulk experiment. Therefore, the glass
transition points determined by DSC are given in Table 1.
The viscosity was measured at 25 and 77 С. The valꢀ
ues obtained for three ILs with the same organosilicon
fragment (compounds 6a, 7, and 8) are very close. This
indicates that in this case the viscosity is affected mainly
by the electrostatic interactions between ions than by the
chemical nature of the salt centers. The introduction of
the second phenyl group into the disiloxane fragment inꢀ
creases the viscosity of the imidazolium IL more than six
and two times at 25 and 77 С, respectively (compounds
6a,b). The temperature effect on the viscosity is also more
pronounced for the IL with two phenyl substituents. An
R = Me (a), Ph (b)
Our attempts to synthesize sodium diphenylmethylsilꢀ
anolate (1b) using toluene, diethyl ether, dioxane, or tetraꢀ
hydrofuran as solvents18 were unseccesful. Under the reꢀ
action conditions, the dissolution of NaOH was slow and
accompanied by the formation of colored products. The
Scheme 2

2704
Russ.Chem.Bull., Int.Ed., Vol. 63, No. 12, December, 2014
Chernikova et al.
Table 1. Physicochemical properties of compounds 6a,b, 7, and 8
position points of compounds 6a and 6b differ insignifiꢀ
cantly. The introduction of the second phenyl group into
the disiloxane fragment increases the decomposition point
by 6 С only.
Thus, four novel ILs containing the organosiloxane
fragment in the cation were synthesized and characterꢀ
ized. The study of their physicochemical properties indiꢀ
cated that compounds 6a and 6b show the highest thermal
stability; however, the viscosity of the latter at 25 С is
very high for its use as a heatꢀtransfer fluid. Therefore,
1,2ꢀdimethylꢀ3ꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisilꢀ
oxanylmethyl)imidazolium bis(trifluoromethylsulfonyl)ꢀ
imide (6a) seems to be the most suitable for use as a heatꢀ
transfer fluid.
Comꢀ
pound
Decomp. Glass trans.


point/С
point/С
/mPa s
/g cm–3
25 С
25 С
77 С
6a
6b
7
397
403
376
344
–60
–37
–58
–58
157.7
970.0
161.2
165.0
20.2
45.2
20.8
23.8
1.32
1.29
1.30
1.32
8
increase in temperature by ~50 С decreases the viscosity
of compound 6b ~20 times.
A comparison of the viscosity of IL 6a and 1ꢀalkylꢀ
2,3ꢀdimethylimidazolium bis(trifluoromethylsulfonyl)ꢀ
imides at 25 С shows that the viscosity of compound 6a
takes the value intermediate between the values obtained
for 1ꢀhexylꢀ and 1ꢀheptylꢀ2,3ꢀdimethylimidazolium bisꢀ
(trifluoromethylsulfonyl)imides: 131 (see Ref. 22) and
170 mPa s (see Ref. 23), respectively. The siloxaneꢀconꢀ
taining substituent in compound 6a contains 14 nonꢀhyꢀ
drogen atoms. Thus, the introduction of siloxane fragꢀ
ments into the ILs instead of aliphatic moieties makes it
possible to obtain compounds with a lower viscosity at
higher molecular weight.
The thermal stability of the synthesized ILs was studꢀ
ied by the TG method in argon. The curves describing the
loss in weight on heating ILs from 25 to 550 С are preꢀ
sented in Fig. 1. All curves are similar, heating to 300 С
does not change the weight of the samples, and at higher
temperatures the weight decreases sharply due to the therꢀ
mal decomposition of the IL.
Experimental
1
H NMR spectra were recorded on a Bruker AM300 spectroꢀ
meter (300 MHz) in DMSOꢀd6 and CDCl3. Residual nonꢀ
deuterated solvent signals (H 2.5 and 7.26) were used as internal
standards. Elemental analysis was carried out on a Carlo Erba
1106 CHN analyzer. Thermogravimetric analysis was performed
on a DerivatographꢀC instrument (MOM, Hungary) in argon at
a heating rate of 10 deg min–1 (weight of samples ~20 mg). Meltꢀ
ing and glass transition temperatures were determined by the
DSC method using a DSCꢀ822e differential scanning caloriꢀ
meter (Mettler Toledo, Switzerland) in the temperature range
from –100 to 25 С at a heating rate of 10 deg min–1 in argon.
The kinematic viscosity was measured using an Ostwald viscomꢀ
eter with a capillary 1.2 mm in diameter at temperatures of 25 and
77 С. The viscometer was calibrated at 25 С using ethylene
glycol (Aldrich, 99.8%, water content <0.01%) as a reference
liquid. The density was measured with a pycnometer with a nomꢀ
inal volume of 2 mL. The pycnometer was calibrated using disꢀ
tilled water.
All organic solvents used were dried and purified by distillaꢀ
tion over CaH2. 1,2ꢀDimethylimidazole and Nꢀmethylpyrrolꢀ
idine (commercial reagents, SigmaꢀAldrich) were dried over
KOH followed by distillation. Trimethylamine was obtained from
the corresponding hydrochloride, dried in a column over solid
KOH, and dissolved in anhydrous acetonitrile. Chloromethylꢀ
dimethylchlorosilane (97%, SigmaꢀAldrich) and lithium bisꢀ
(trifluoromethylsulfonyl)imide (99%, Acros Organics) were used
without additional purification. Methyldiphenylethoxysilane and
dimethylphenylethoxysilane were obtained by the ethoxylation
of the corresponding chlorosilanes (98%, SigmaꢀAldrich) using
a standard procedure.26 Sodium dimethylphenylꢀ and diphenylꢀ
methylsilanolates (1a and 1b) were obtained by a procedure18
adapted for the corresponding organoethoxysilanes.
The behavior of similar ILs under the TG conditions
shows that the thermal stability is an additive value and
the contribution of each ion is determined by the chemical
nature of the ion.24,25 The thermal stability of cations with
the siloxane fragment decreases in the following order:
imidazolium > pyrrolidinium > ammonium. The decomꢀ
m (%)
100
80
6b
60
Sodium dimethylphenylsilanolate (1a) was synthesized from
dimethylphenylethoxysilane (26.0 g, 0.144 mol) and NaOH (5.80 g,
0.145 mol) in 1,2ꢀdimethoxyethane (50 mL). The reaction mixꢀ
ture was stirred at ~50 С until the alkali was completely disꢀ
solved, and then volatile components were removed under reꢀ
duced pressure. The obtained salt was dissolved in toluene
(50 mL), and the solution was evaporated in vacuo. This proceꢀ
dure was repeated two times more to remove trace amounts of
EtOH. Toluene (60 mL) was added again to the obtained crysꢀ
talline mixture, and hexane (10 mL) was added after the crystals
6a
40
20
7
8
100
200
300
400
500
T/С
Fig. 1. TG curves of compounds 6a,b, 7, and 8 (10 deg min–1
,
in argon).

Siloxaneꢀfunctionalized ionic liquids
Russ.Chem.Bull., Int.Ed., Vol. 63, No. 12, December, 2014 2705
dissolved. The formed turbid solution was filtered and evaporatꢀ
ed in vacuo. Then sodium dimethylphenylsilanolate was washed
with hexane to remove unreacted dimethylphenylethoxysilane.
After drying in vacuo (0.1 Torr), solid sodium dimethylphenylsiꢀ
lanolate was obtained in a yield of 21.4 g (85%).
(s, 3 H, NМе); 3.13 (s, 2 H, NCH2Si); 3.35—3.61 (m, 4 H,
NCH2CH2CH2CH2N); 7.33—7.61 (m, 5 H, Ph).
Trimethyl(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisiloxanylmethꢀ
yl)ammonium chloride (5) was obtained according to the proceꢀ
dure for synthesis of compound 3a from compound 2a (10.0 g,
0.038 mol) and trimethylamine (2.30 g, 0.039 mol) in acetoꢀ
nitrile (20 mL) in an autoclave. The yield was 8.0 g (67%).
1H NMR (300 MHz, DMSOꢀd6), : 0.24 (s, 6 H, CH2SiМе2O);
0.37 (s, 6 H, OSiМе2Ph); 3.14 (s, 2 H, NCH2Si + s, 9 H, NМе);
7.35—7.59 (m, 5 H, Ph).
1,2ꢀDimethylꢀ3ꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisiloxꢀ
anylmethyl)imidazolium bis(trifluoromethylsulfonyl)imide (6a).
Compound 3a (9.5 g, 0.027 mol) was dissolved in distilled water
(15 mL) and added to lithium bis(trifluoromethylsulfonyl)imide
(7.75 g, 0.027 mol). Then the mixture was stirred for 15 min,
dichloromethane (50 mL) was added, and the mixture was transꢀ
ferred to a separatory funnel. The organic layer was separated
and washed with distilled water to the negative reaction to chloꢀ
ride ion with silver chloride. Dichloromethane was distilled off
on a rotary evaporator, and compound 6a was dried in vacuo
(0.1 Torr), gradually increasing temperature from 25 to 80 С.
A viscous colorless liquid was obtained in a yield of 15.0 g (93%).
Found (%): C, 35.96; H, 4.61; F, 19.00; N, 6.95; S, 10.66; Si, 9.41.
C18H27F6N3O5S2Si2. Calculated (%): C, 36.05; H, 4.54; F, 19.01;
N, 7.01; S, 10.69; Si, 9.37. 1H NMR (300 MHz, DMSOꢀd6), :
0.15 (s, 6 H, CH2SiМе2O); 0.29 (s, 6 H, OSiМе2Ph); 2.45 (s, 3 H,
CМе); 3.68 (s, 3 H, NМе); 3.81 (s, 2 H, NCH2Si); 7.33—7.62
(m, 5 H, Ph + d, 2 H, C(5)H, C(4)H).
1,2ꢀDimethylꢀ3ꢀ(1´,1´,3´ꢀtrimethylꢀ3´,3´ꢀdiphenyldisiloxanꢀ
ylmethyl)imidazolium bis(trifluoromethylsulfonyl)imide (6b) was
obtained similarly to the procedure described for the synthesis of
compound 6a from compound 3b (12.2 g, 0.029 mol) and lithiꢀ
um bis(trifluoromethylsulfonyl)imide (8.61 g, 0.03 mol) in disꢀ
tilled water (15 mL). A viscous colorless liquid was obtained in
a yield of 17.4 g (91%). Found (%): C, 41.68; H, 4.50; F, 17.19;
N, 6.31; S, 9.63; Si, 8.53. C23H29F6N3O5S2Si2. Calculated (%):
C, 41.74; H, 4.42; F, 17.22; N, 6.35; S, 9.69; Si, 8.49. 1H NMR
(300 MHz, DMSOꢀd6), : 0.17 (s, 6 H, OSiМе2CH2); 0.59 (s, 3 H,
OSiМеPh2); 2.39 (s, 3 H, CМе); 3.63 (s, 3 H, NМе); 3.86 (s, 2 H,
NCH2Si); 7.38—7.55 (m, 10 H, Ph + d, 2 H, C(5)H, C(4)H).
1ꢀMethylꢀ1ꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisiloxanylꢀ
methyl)pyrrolidinium bis(trifluoromethylsulfonyl)imide (7) was obꢀ
tained by the procedure used for the synthesis of compound 6a
from compound 4 (8.8 g, 0.025 mol) and lithium bis(trifluoroꢀ
methylsulfonyl)imide (7.46 g, 0.026 mol) in distilled water
(15 mL). A viscous colorless liquid was obtained in a yield of
13.9 g (95%). Found (%): C, 36.66; H, 5.23; F, 19.32; N, 4.75;
S, 10.84; Si, 9.57. C18H30F6N2O5S2Si2. Calculated (%): C, 36.72;
H, 5.14; F, 19.36; N, 4.76; S, 10.89; Si, 9.54. 1H NMR (300 MHz,
DMSOꢀd6), : 0.24 (s, 6 H, CH2SiМе2O); 0.37 (s, 6 H, OSiМе2Ph);
2.05 (m, 4 H, CH2CH2CH2CH2); 3.01 (s, 3 H, NМе); 3.09
(s, 2 H, NCH2Si); 3.30—3.61 (m, 4 H, NCH2CH2CH2CH2N);
7.31—7.64 (m, 5 H, Ph).
Sodium methyldiphenylsilanolate (1b) was obtained using
a procedure similar to the synthesis of compound 1a from methylꢀ
diphenylethoxysilane (33.1 g, 0.137 mol) and NaOH (5.47 g,
0.137 mol) in 1,2ꢀdimethoxyethane (60 mL). Solid sodium
methyldiphenylsilanolate was obtained in a yield of 24.1 g (75%).
1ꢀChloromethylꢀ1,1,3,3ꢀtetramethylꢀ3ꢀphenyldisiloxane (2a).
Freshly distilled chloromethyldimethylchlorosilane (17.7 g,
0.124 mol) was dissolved in anhydrous hexane (50 mL). A soluꢀ
tion of sodium dimethylphenylsilanolate (21.4 g, 0.123 mol) in
anhydrous toluene (40 mL) was slowly added dropwise with slight
cooling (~15 С) and vigorous stirring. The bulky precipitate
formed was filtered and two times washed with small portions of
hexane. The filtrate was concentrated in vacuo and compound 2a
was isolated by vacuum fractionation (87—90 С, 1 Torr). The
yield was 26.3 g (82%). 1H NMR (300 MHz, CDCl3), : 0.25
(s, 6 H, CH2SiMe2O); 0.41 (s, 6 H, OSiMe2Ph); 2.75 (s, 2 H,
SiCH2); 7.35—7.66 (m, 5 H, Ph).
1ꢀChloromethylꢀ1,1,3ꢀtrimethylꢀ3,3ꢀdiphenyldisiloxane (2b)
was synthesized similarly to the procedure described for the synꢀ
thesis of compound 2a from chloromethyldimethylchlorosilane
(7.5 g, 0.052 mol) and sodium methyldiphenylsilanolate (12.3 g,
0.052 mol). Compound 2a was isolated by vacuum fractionꢀ
ation (146—150 С, 1 Torr). The yield was 13.5 g (81%).
1H NMR (300 MHz, CDCl3), : 0.25 (s, 6 H, CH2SiМе2O);
0.68 (s, 3 H, OSiМеPh2); 2.74 (s, 2 H, SiCH2); 7.35—7.68
(m, 10 H, Ph).
1,2ꢀDimethylꢀ3ꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisilꢀ
oxanylmethyl)imidazolium chloride (3a). A mixture of compound 2a
(9.0 g, 0.035 mol), 1,2ꢀdimethylimidazole (3.46 g, 0.036 mol),
and acetonitrile (20 mL) was placed in a tube, which was deꢀ
gassed and sealed in vacuo. The tube was stored for 36 h at 80 С.
After cooling, the tube was opened, and the reaction mixture
was removed and evaporated under reduced pressure. The obꢀ
tained salt was washed with a small amount of toluene and disꢀ
solved in a hot THF—acetonitrile (9 : 1) mixture. The crystals
precipitated after cooling were filtered and dried in vacuo
(0.1 Torr). The yield was 9.5 g (74%). 1H NMR (300 MHz,
DMSOꢀd6), : 0.15 (s, 6 H, CH2SiМе2O); 0.29 (s, 6 H,
OSiМе2Ph); 2.46 (s, 3 H, CМе); 3.70 (s, 3 H, NМе); 3.83 (s, 2 H,
NCH2Si); 7.37—7.62 (m, 5 H, Ph + d, 2 H, C(5)H, C(4)H).
1,2ꢀDimethylꢀ3ꢀ(1´,1´,3´ꢀtrimethylꢀ3´,3´ꢀdiphenyldisiloxꢀ
anylmethyl)imidazolium chloride (3b) was obtained using a proceꢀ
dure similar to the method of synthesis of compound 3a from
compound 2b (13.5 g, 0.042 mol), 1,2ꢀdimethylimidazole (4.04 g,
0.042 mol), and acetonitrile (20 mL). The yield was 12.2 g (70%).
1H NMR (300 MHz, DMSOꢀd6), : 0.16 (s, 6 H, OSiМе2CH2);
0.58 (s, 3 H, OSiМеPh2); 2.39 (s, 3 H, CМе); 3.63 (s, 3 H,
NМе); 3.87 (s, 2 H, NCH2Si); 7.34—7.60 (m, 10 H, Ph + d, 2 H,
C(5)H, C(4)H).
Trimethylꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisiloxanylꢀ
methyl)ammonium bis(trifluoromethylsulfonyl)imide (8) was obꢀ
tained similarly to the procedure developed for the synthesis of
compound 6a from compound 5 (8.0 g, 0.025 mol) and lithium
bis(trifluoromethylsulfonyl)imide (7.18 g, 0.025 mol) in distilled
water (15 mL). A viscous colorless liquid was obtained in a yield
of 12.8 g (91%). Found (%): C, 34.27; H, 5.10; F, 20.24; N, 4.94;
S, 11.35; Si, 10.03. C16H28F6N2O5S2Si2. Calculated (%):
1ꢀMethylꢀ1ꢀ(1´,1´,3´,3´ꢀtetramethylꢀ3´ꢀphenyldisiloxanylꢀ
methyl)pyrrolidinium chloride (4) was obtained using a procedure
described for the synthesis of compound 3a from compound 2a
(9.0 g, 0.035 mol), Nꢀmethylpyrrolidine (3.06 g, 0.036 mol), and
acetonitrile (20 mL). The yield was 8.8 g (73%). 1H NMR
(300 MHz, DMSOꢀd6), : 0.25 (s, 6 H, CH2SiМе2O); 0.37
(s, 6 H, OSiМе2Ph); 2.05 (m, 4 H, CH2CH2CH2CH2); 3.04

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Russ.Chem.Bull., Int.Ed., Vol. 63, No. 12, December, 2014
Chernikova et al.
C, 34.15; H, 5.02; F, 20.26; N, 4.98; S, 11.40; Si, 9.98. 1H NMR
(300 MHz, DMSOꢀd6), : 0.24 (s, 6 H, CH2SiМе2O); 0.38
(s, 6 H, OSiМе2Ph); 3.10 (s, 2 H, NCH2Si); 3.11 (s, 9 H, NМе);
7.36—7.60 (m, 5 H, Ph).
10. S. Lee, Y. Jeon, Y. Lim, Y. Cho, S. Lee, W. Kim, Bull.
Korean Chem. Soc., 2013, 34, 2583.
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Roum. Chim., 2002, 47, 551.
12. A. R. Bassindale, M. Borbaruah, S. J. Glynn, D. J. Parker,
P. G. Taylor, J. Chem. Soc., Perkin Trans. 2, 1999, 10, 2099.
13. H. Niedermeyer, M. A. Ab Rani, P. D. Lickiss, J. P. Hallett,
T. Welton, A. J. P. White, P. A. Hunt, Phys. Chem. Chem.
Phys., 2010, 12, 2018.
This work was financially supported by the Russian
Science Foundation (Project No. 14ꢀ19ꢀ00503).
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Received October 3, 2014;
in revised form October 28, 2014