1,1-Diethynylsilacycloalkanes and propellanes based thereon

Article abstract of DOI:10.1023/A:1012374900270

Previously unknown 1,1-diethylnylsilacycloalkanes (CH₂)_nSi(C=CH)₂ (n = 3, 4) were prepared by the reaction of HC=CMgBr with 1,1-dichlorosilacycloalkanes (CH₂)_nSiCl₂ (n = 3, 4). The reaction of (CH₂)₄Si(C=CMgBr)₂ with (CH₂)₄SiCl₂ in THF under conditions of high dilution gives cyclo(tetramethylene)-silethynes [(CH₂)₄SiC=C]₄ with an admixture of cyclodi(tetramethylene)silethyne [(CH₂)₄SiC=C]₂. The reaction of Me₂Si(C=CSiMe₂C=CMgBr)₂ with (CH₂)₄SiCl₂ was used to prepare 1,1,4,4,7,7-hexamelhyl-10,10-tetramethylene-1,4,4,10-tetrasilacyclododeca-2,5,8, 11-tetrayne.

Full text of DOI:10.1023/A:1012374900270

Russian Journal of General Chemistry, Vol. 71, No. 4, 2001, pp. 537 539. Translated from Zhurnal Obshchei Khimii, Vol. 71, No. 4, 2001,
pp. 578 580.
Original Russian Text Copyright
2001 by Voronkov, Zhilitskaya, Yarosh, Burnashova, Albanov, Klyba.
1,1-Diethynylsilacycloalkanes and Propellanes Based Thereon
M. G. Voronkov, L. V. Zhilitskaya, O. G. Yarosh,
T. D. Burnashova, A. I. Albanov, and L. V. Klyba
Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, Russia
Received December 23, 1999
Abstract Previously unknown 1,1-diethylnylsilacycloalkanes (CH2)nSi(C CH)2 (n = 3, 4) were prepared
by the reaction of HC CMgBr with 1,1-dichlorosilacycloalkanes (CH2)nSiCl2 (n = 3, 4). The reaction of
(CH2)4Si(C CMgBr)2 with (CH2)4SiCl2 in THF under conditions of high dilution gives cyclo(tetramethylene)-
silethynes [(CH2)4SiC C]4 with an admixture of cyclodi(tetramethylene)silethyne [(CH2)4SiC C]2. The re-
action of Me2Si(C CSiMe2C CMgBr)2 with (CH2)4SiCl2 was used to prepare 1,1,4,4,7,7-hexamethyl-10,10-
tetramethylene-1,4,4,10-tetrasilacyclododeca-2,5,8,11-tetrayne.
Earlied we described 1-ethynyl-1-methylsilacyclo-
butane and 1-ethynyl-1-methylsilacyclopentane
1,1-Diethynylsilacyclobutane and 1,1-diethynyl-
silacyclopentane are colorless liquids with a specific
ethynylsilane odor. Due to presence of a mobile
acetylenic hydrogen atom they can be easily con-
verted to highly reactive organomagnesium deriva-
tives. The reaction of 1,1-bis(bromomagnesioethynyl)-
silacyclopentane with 1,1-dichlorosilacyclopentane in
THF under conditions of high dilution gives a mixture
of bi- and tetracyclo(tetramethylene)silethynes: 1,1,4,4-
di(tetramethylene)-1,4-disilacyclohexa-2,5-diyne and
1,1,4,4,7,7,10,10-tetra(tetramethylene)-1,4,7,10-tetra-
silacyclododeca-2,5,8,11-tetrayne, respectively.
[1, 2]. Proceeding with these studies, we synthesized
1,1-diethylnylsilacyclobutane (I) and 1,1-diethynyl-
silacyclopentane (II). They were obtained by the
reactions of ethynylmagnesium bromides with respec-
tively 1,1-dichlorosilacyclobutane and 1,1-dichloro-
silacyclopentane in THF.
(CH2)nSiCl2 + 2BrMgC CH
(CH2)nSi(C CH)2,
I, II
n = 3 (I), 4 (II).
SiC CSi
C C
C
C
+
Si
Si
Si(C CMgBr)2 +
SiCl2
C
C
C C
SiC CSi
III
IV
Propellane IV was isolated as crystals (Table 1) and
silane was reacted with 1,1-dichlorosilacyclopentane
to obtain 1,1,4,4,7,7-hexamethyl-10,10-tetramethyl-
ene-1,4,7,10-tetrasilacyclododeca-2,5,8,11-tetrayne
(V).
1
characterized by H, 13C, and 29Si NMR spectroscopy
(Table 2). The mass spectrum of the resulting sample
contains, along with the base peak at m/e 432 (com-
pound IV), a lower intensity peak at m/e 216 assigna-
ble to propellane III. This assignment is supported by
Macrocyclic ethynylsilanes IV, V are colorless
high-melting (>200 C) crystals insoluble in nonpolar
solvents. The yields, constants, and elemental
analyses of all the synthesized compounds are listed
in Table 1. The structures of the compounds were
1
the observation in the H and 13C NMR spectra of
signals due to both III and IV (Table 2).
Bis(bromomagnesiodimethylsilylethynyl)dimethyl-
1070-3632/01/7104-0537$25.00 2001 MAIK Nauka/Interperiodica

538
VORONKOV et al.
Me
Me
Me SiC CSi Me
C CSiMe2C CMgBr
SiMe2
C
1C
+
Cl2Si
C2
C
SiC CSi Me
Me
C CSiMe2C CMgBr
V
1
established based on their H, 13C, and 29Si NMR
ture 250 C, ionizing energy 60 eV. The NMR spectra
were measured on a Jeol FX-90Q spectrometer for
15% solutions in CDCl3, internal reference TMS.
(Table 2) and mass spectra (Table 1).
EXPERIMENTAL
1,1-Dichlorosilacyclobutane was prepared by the
reaction of trichloro(3-chloropropyl)silane with
magnesium in ether. 1,1-Dichlorosilacyclopentane was
The mass spectra were obtained on an LKB-2091
GC MS system with direct inlet, ion sorce tempera-
Table 1. Yields, elemental analyses, and physicochemical characteristics of the synthesized compounds
bp,
C
(p, mm)
Found, %
H
Calculated, %
H
Comp. Yield,
m/e
(Irel, %)
d240
n2D0
Formula
no.
%
C
Si
C
Si
I
65.0
61.0
8.5
46 (50) 0.8996 1.4860 69.82
64 (25) 0.9066 1.4790 71.05
6.68
8.18
7.43
7.40
23.37 C7H8Si
20.16 C8H10Si
25.30 C24H32Si4 66.60
31.88 C18H26Si4 60.94
69.93
71.57
6.70
7.51
7.45
7.39
23.36
20.92
25.25 432 (100)
31.67 354 (100)
II
IVa
66.57
b
c
V
9.0
60.46
a
b
c
Contains an admixture of compound III, m/e 216 (13).
Decomposes at 370 C.
mp 237 C.
Table 2. 1H, 13C, and 29Si NMR spectra of the synthesized compounds
1H NMR spectrum, , ppm
13C NMR spectrum, C, ppm
Comp.
no.
29Si NMR spectrum,
1, ppm
2
3
2
5
3
4
Si
CH
SiC
CH
Si
Si
4
5
I a
II
2.68
2.52
84.03
84.81
95.99
95.78
35.83
27.40
0.90 s (2, 5)
1.54 s (3, 4)
1.08 s (2, 5)
1.68 s (3, 4)
0.87 s (2, 5)
1.62 s (3, 4)
0.86 s (2, 5)
13.57 s (2, 5)
26.67 s (3, 4)
11.26 s (2, 5)
27.00 s (3, 4)
12.83 s (2, 5)
26.62 s (3, 4)
12.94 s (2, 5)
III
IV
114.83
114.83
29.67
29.67
30.00
V b
112.70
113.87
114.06
115.76
1.62 s (3, 4)
26.60 s (3, 4)
Si 2
a 1
13
H NMR spectrum, , ppm: 1.34 (2, 4) (J
8.5 Hz), 2.21 t (3) (J
8.5 Hz) ( 3 ). C NMR spectrum,
, ppm:
C
HH
HH
4
b 1
13
29
15.4 s (2, 4), 18.1 s (3).
spectrum,
H NMR spectrum, , ppm: 0.31 s (SiMe). C NMR spectrum, , ppm: 0.85 s (SiMe). Si NMR
C
, ppm: 41.60 (Si).
Si
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 4 2001

1,1-DIETHYNYLSILACYCLOALKANES AND PROPELLANES BASED THEREON
539
prepared by the reaction of 1,4-dibromobutane with a
mixture of magnesium with tetrachlorosilane. Their
constants were consistent with published data [3, 4].
of 1,1-dichlorosilacyclopentane in 75 ml ether.
Further workup was performed as described above.
4
High-vacuum (10
mm) distillation gave 1.3 g
(9.0%) of compound V (Table 1).
1,1-Diethynylsilacyclobutane (I). To 7.05 g of
1,1-dichlorosilacyclobutane in 50 ml of ether we
added dropwise with stirring HC CMgBr obtained
from 2.43 g of Mg, 10.9 g of EtBr, and acetylene in
100 ml of THF. The mixture was heated for 0.5 h and
then decomposed with water and 5% HCl. Usual
workup followed by drying with calcined CaCl2,
removal of the solvents in a water-jet-pump vacuum,
and vacuum distillation of the residue gave 3.9 g
(65%) of compound I (Table 1).
Compound IV was prepared in a similar way
(Table 1). According to the mass spectrum, it con-
tained an admixture of compound III.
REFERENCES
1. Voronkov, M.G., Yarosh, O.G., Ivanova, Z.G., Ro-
man, V.K., and Albanov, A.I., Izv. Akad. Nauk SSSR,
Ser. Khim., 1987, no. 6, pp. 1403 1406.
2. Voronkov, M.G., Yarosh, O.G., Roman, V.K., and Al-
banov, A.I., Metalloorg. Khim., 1990, vol. 3, no. 6,
pp. 1423 1425.
Compound II (Table 1) was prepared in a similar
way.
1,1,4,4,7,7-Hexamethyl-10,10-tetramethylene-
1,4,7,10-tetrasilacyclododeca-2,5,8,11-tetrayne (V).
To 50 ml of ether we simultaneously added, dropwise
with stirring, Me2Si(C CSiMe2C CMgBr)2 (prepared
from 2.43 g of Mg, 10.9 g of EtBr, and 13.6 g of
Me2Si(C CSiMe2C CH)2 in 75 ml of THF) and 7.6 g
3. Plate, A.F., Momma, N.A., and Egorov, Yu.P., Dokl.
Akad. Nauk SSSR, 1954, vol. 97, no. 5, pp. 847 850.
4. Vdovin, V.M., Nametkin, N.S., and Grinberg, P.L.,
Dokl. Akad. Nauk SSSR, 1963, vol. 97, no. 4,
pp. 799 801.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 4 2001