Reaction of N,N′-bis(trimethylsilyl)-N-methyl-N′-arylureas with chloro(chloromethyl)dimethylsilane [7]

Full text of DOI:10.1023/B:RUGC.0000042443.05630.9c

Russian Journal of General Chemistry, Vol. 74, No. 6, 2004, pp. 971 972. Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 6, 2004,
pp. 1051 1052.
Original Russian Text Copyright
2004 by M. Pudovik, Kibardina, A. Pudovik.
LETTERS
TO THE EDITOR
Reaction of N,N -Bis(trimethylsilyl)-N-methyl-N -arylureas
with Chloro(chloromethyl)dimethylsilane
M. A. Pudovik, L. K. Kibardina, and A. N. Pudovik
Arbuzov Institute of Organic and Physical Chemistry, Kazan Research Center,
Russian Academy of Sciences, Kazan, Tatarstan, Russia
Received October 17, 2003
We previously showed that the reaction of chloro-
(chloromethyl)dimethylsilane with bis(N-methyl-N-tri-
methylsilylamido)methylphosphonate is accompanied
by separation of 2 equiv of chlorotrimethylsilane and
provides 1,2,3,4,4-pentamethyl-1,3-diaza-2-phospha-
4-silolidin-2-one [1]. With the purpose of investigate
the possibility of formation of new silacyclanes on
the basis of chloromethyl derivatives of silicon we
turned to reaction of N,N -bis(trimethylsilyl)-N-methyl-
N -phenylurea (Ia) and N,N -bis(trimethylsilyl)-
N-methyl-N -p-chlorophenylurea (Ib) with chloro-
(chloromethyl)dimethylsilane. Silylated urea Ib was
prepared from heptamethyldisilazane and p-chloro-
phenyl isocyanate.
MeN(SiMe3)2 + p-ClC6H4NCO
MeN C(O) NC6H4Cl-p
SiMe3 SiMe3
Ib
1
The H NMR spectrum of compound Ib reveals
silylation with separation of a molecule of chlorotri-
methylsilane and intermediate formation of urea III.
The latter undergoes cyclization involving the chlo-
romethyl group and resulting in separation of a further
molecule of trimethylchlorosilane and formation of
silacyclanes IVa and IVb.
nonequivalence of trimethylsilyl protons. They are
presented by two singlets at 0.71 and 0.53 ppm.
Methyl protons give a singlet at
2.73 ppm.
The reactions of ureas Ia and Ib with chloro-
(chloromethyl)dimethylsilane(II) involves initial trans-
Me
N
O=C
Me
O Me
O MeMe
ArN C N Si Me
SiMe3 CH2Cl
Si Me
ArN C NSiMe3 + ClCH2SiMe2Cl
Me3SiCl
Me3SiCl
N
SiMe3
Ar
Ia, Ib
II
III
IVa, IVb
The IR spectra of compounds IVa and IVb contain
group on silicon ( 0.40 ppm), the methyl group on
nitrogen ( 2.78 ppm), and the methylene group (
2.95) are observed. The intensity ratio of these three
signals is 6:3:2. In addition, a multiplet of phenyl
1
strong carbonyl absorption band at 1668 cm . In
1
the H NMR spectrum of compound IVa, there are
three singlets characteristic of protons of the methyl
1070-3632/04/7406-0971 2004 MAIK Nauka/Interperiodica

972
PUDOVIK et al.
protons is observed at 7.06 7.37 ppm. Similar com-
pounds were previously obtained by decomposition
of ten-membered Si,N-containing heterocycles [2].
stillation of the reaction mixture gave 0.8 g (32%) of
silacyclane IVb, bp 136 140 C (0.08 mm Hg), mp
60 62 C. Found, %: C 52.19; H 5.76; N 10.15; Si
10.17. C11H15ClN2OSi. Calculated, %: C 52.90; H
5.88; N 10.19; Si 10.98.
N,N -Bis(trimethylsilyl)-N-p-chlorophenyl-N-
methylurea (Ib). p-Chlorophenyl isocyanate, 3.07 g,
and 3.50 g of heptamethyldisilazane were dissolved
in 40 ml of anhydrous ether. The reaction involved
heat evolution. After 12 h, the solvent was removed to
obtain 5.1 g (78%) of carbamide I, mp 88 C. Found,
%: N 8.29; Si 8.33. C14H22ClN2OSi. Calculated,
%: N 8.51; Si 8.51.
The IR spectra were recorded on a UR-20 spec-
1
trometer in the range 500-3600 cm for suspensions
1
in mineral oil. The H NMR spectra were measured
on a Bruker WM-250c spectrometer (250.13 MHz)
against external TMS.
ACKNOWLEDGMENTS
3,4,4-Trimethyl-1-phenyl-1,3-diaza-4-silolidin-2-
one (IVa). A solution of 3.0 g of urea Ia and 1.4 g of
chlorosilane II in 40 ml of anhydrous ether was re-
fluxed for 2 h. Distillation of the reaction mixture
gave 1.3 g (59%) of silacyclane IVa, bp 145 C
(0.08 mm Hg). Found, %: N 12.69; Si 12.86. C11H16
N2OSi. Calculated, %: N 12.73; Si 12.73.
The work was financially supported by the Russian
Foundation for Basic Research (project no. 03-03-
33064).
REFERENCES
1. Pudovik, A.N., Kibardina, L.K., and Pudovik, M.A.,
1-(p-Chlorophenyl)-3,4,4-trimethyl-1,3-diaza-4-
silolidin-2-one (IVb). A solution of 3.3 g of urea Ib
Zh. Obshch. Khim., 1997, vol. 67, no. 12, p. 2053.
and 1.4
g
of chlorosilane II in 40 ml of
2. Mironov, V,F., Sheludyakov, V.D., and Rodionov, E.S.,
anhydrous ether was refluxed for 1 h. Vacuum di-
Zh. Obshch. Khim., 1973, vol. 43, no. 11, p. 2573.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 6 2004