Highly unsaturated macrocyclic silahydrocarbons containing exocyclic phenyl groups

Article abstract of DOI:10.1023/B:RUGC.0000016020.37433.f6

A series of 12- and 18-membered macrocycloethynes and macrocyclosilethenesilethynes, containing peripheral methyl and phenyl groups was prepared by organomagnesium sysnthesis under conditions of high dilution. One of these compounds contains an endocyclic

Full text of DOI:10.1023/B:RUGC.0000016020.37433.f6

Russian Journal of General Chemistry, Vol. 73, No. 10, 2003, pp. 1552 1554. Translated from Zhurnal Obshchei Khimii, Vol. 73, No. 10, 2003,
pp. 1645 1647.
Original Russian Text Copyright
2003 by O. Yarosh, Zhilitskaya, N. Yarosh, Albanov, Voronkov.
Highly Unsaturated Macrocyclic Silahydrocarbons
Containing Exocyclic Phenyl Groups
O. G. Yarosh, L. V. Zhilitskaya, N. K. Yarosh, A. I. Albanov, and M. G. Voronkov
Favorskii Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, Russia
Received February 14, 2002
Abstract A series of 12- and 18-membered macrocycloethynes and macrocyclosilethenesilethynes,
containing peripheral methyl and phenyl groups was prepared by organomagnesium sysnthesis under condi-
tions of high dilution. One of these compounds contains an endocyclic 1,4-phenylene bridge.
Until now octaphenylcyclotetrasilethyne and dode-
caphenylcyclohexasilethyne, prepared in 1 and 23%,
Me
Me SiC CMgBr
Y
respectively, have been the only reported representa-
tives of cyclosilethynes with exocyclic phenyl groups
[1].
+ 2Cl2SiMePh
2
Me SiC CMgBr
Proceeding with research on highly unsaturated
macrocyclic silahydrocarbons [2, 3] we have syn-
thesized a series of cyclosilethynes and cyclosilethene-
silethynes containing exocyclic methyl and phenyl
groups I III. The first macrocyclic highly unsaturated
aliphatic silahydrocarbon with an exocyclic 1,4-phe-
nylene bridge has also been prepared (compound IV).
Me
Me
Me
Me
Me
Si Y Si
C
C
Me
C
C
C
Ge
Ge
C
Me
C
Me
C
Si Y Si
The reaction of bis(bromomagnesioethyl)dimethyl-
silane with dichloro(methyl)(phenyl)silane gave
1,4,4,7,10,10-hyxamethyl-1,7-diphenyl-1,4,7,10-tetra-
silacyclododeca-2,5,8,11-tetrayne (I).
Me
Me
Me
II, III
Y = C C (II), (E)-CH=CH (III).
2Me2Si(C CMgBr)2 + 2Cl2SiMePh
Me
Me Si C C Si
Me
Finally, the reaction of (E)-bis[(bromomagnesio-
ethynyl)dimethylsilyl)ethene with 1,4-bis(methyldi-
fluorosilyl)benzene was used to synthesize a unique
18-membered macrocyclosilethenesilethyne contain-
ing a 1,4-phenylene bridge inside the macroring, (E,E)-
1,4,4,7,7,10,13,13,16,16-decamethyl-1,10(1 ,4 -phe-
nylene)-1,4,7,10,13,16-hexasilacyclooctadeca-5,14-
diene-2,8,11,17-tetrayne (IV).
C
C
C
C
Si C C Si Me
Me Me
I
The reactions all formed great amounts of polymers.
Their structure, properties, and transformations are
presently under investigation.
Similarly, by reacting bis[(bromomagnesioethynyl)-
dimethylsilyl]ethyne or (E)-bis[(bromomagnesio-
ethynyl)dimethylsilyl]ethene with dichloro(methyl)-
(phenyl)silanes we obtained 1,4,4,7,7,10,13,13,16,16-
decamethyl-1,10-diphenyl-1,4,7,10,13,16-hexasila-
cyclooctadeca-2,5,8,11,14,17-hexayne (II) and (E,E)-
1,4,4,7,7,10,13,13,16,16-decamethyl-1,10-diphenyl-
1,4,7,10,13,16-hexasilacyclooctadeca-5,14-diene-2,8,
11,17-tetrayne (III), respectively.
Compounds I IV are colorless high-melting crystals
poorly soluble in hexane and readily soluble in benzene
and chloroform. Their melting points, yields, elemental
analyses, and mass spectral characteristics are given
1
in Table 1. The H, 13C, and 29Si NMR spectra of
compounds I IV are presented in Table 2.
1070-3632/03/7310-1552$25.00 2003 MAIK Nauka/Interperiodica

HIGHLY UNSATURATED MACROCYCLIC SILAHYDROCARBONS
Table 1. Properties of compounds I IV
1553
Found, %
H
Formula
Calculated, %
H
Comp. Yield,
mp,
C
Mass spectrum,
m/z (Irel, %)
no.
%
C
Si
C
Si
24.80
27.30
27.11
31.03
I
II
5.5
4.3
230
232
203
240
452 (20)
616 (16)
620 (100)
542 (20)
68.95
65.97
65.92
62.08
6.42
6.50
7.25
7.28
24.29
26.57
26.88
31.33
C26H28Si4
C34H40Si6
C34H44Si6
C28H38Si6
68.98
66.16
65.3
6.23
6.53
7.14
7.05
III
IV
10
4.5
61.92
Table 2. 1H, 13C, and 29Si spectra of compounds I IV
1H NMR spectrum, , ppm
13C NMR spectrum, C, ppm
29Si NMR spectrum,
Si, ppm
Comp.
no.
Si11CH3 Si21CH3
C6H5 CH=CH Si11CH3 Si12CH3
C6H5
SiC
SiCH=
Si1
Si2
I
0.36
0.55
7.41,
7.70
0.86
1.33
128.08,
130.28,
132.49,
134.18
134.03,
129.95,
127.85
128.02,
130.00,
134.03
125.11,
131.31,
135.75
112.39,
115.69
41.12
46.25
II
III
IV
0.36
0.26
0.26
0.56
0.60
0.56
7.40,
7.71
0.13
0.48
112.39
110.63,
108.84
109.40, 148.44,
114.68 148.83
41.10
25.26
25.05
46.08
46.76
46.52
7.40,
7.75
6.74
6.71
1.84,
1.78
1.65,
1.69
7.52,
7.57
0.24
0.30
108.96, 148.56
115.39
Me
Si
C
C
Me
Me
Me
C
C
C
Me
Me
Si
Si
Me SiC CMgBr
F2SiMe
F2SiMe
CH
CH
CH
2
+
HC
HC
HC
Me
Me
Me
Me
Si
Si
Me SiC CMgBr
Me
C
C
C
Si
Me
IV
Previously unknown 1,4-bis[difluoro(methyl)silyl]-
benzene was synthesized by the reaction of 1,4-di-
bromobenzene with methyltrimethoxysilane and
magnesium in ether, followed by fluorination of the
resulting 1,4-bis(methyldimethoxysilyl)benzene with
40% HF.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 73 No. 10 2003

1554
YAROSH et al.
Compounds II IV were prepared in a similar way.
Br
Br + Mg + (MeO)3SiMe
1,4-Bis[difluoro(methyl)silyl]benzene (VI). To
15.0 g of Mg and 68 g MeSi(OMe3)3 in 500 ml of
ether, we added dropwise with stirring 59 g of BrC6
H4Br in 250 ml of ether. The mixture was refluxed
for 12 h. The precipitate and unreacted magnesium
were filtered off and washed with ether on the filter.
The ether was distilled off, and the residue was dis-
tilled in a vacuum to obtain 50.5 g of compound V.
After repeated distillation the latter was treated with
40% HF. The resulting 1,4-bis[difluoro((methyl)silyl]-
benzene was separated and distilled in a vacuum.
Yield 10.1 g (20%), bp 80 81 C (8 mm), d240 1.1348,
n2D0 1.4870.
Me(MeO)2Si
Si(OMe)2Me
SiF2Me
V
HF
MeF2Si
VI
EXPERIMENTAL
The mass spectra were obtained on an LKB-2091
GC MS system with direct inlet (250 C), ionizing
energy 60 eV. The NMR spectra were measured on a
Bruker DRX-400 instrument for 15% solutions in
CDCl3, internal reference TMS.
ACKNOWLEDGMENTS
The work was financially supported by the Russian
Foundation for Basic Research (project no. 00-15-
97395).
1,4,4,7,10,10-Hexamethyl-1,7-diphenyl-1,4,7,10-
tetrasilacyclododeca-2,5,8,11-tetrayne (I). To 50 ml
of ether we simultaneously added dropwise with stir-
ring Me2Si(C CMgBr)2 prepared from 2.43 g of Mg,
10.9 g of EtBr, and 5.4 g of Me2Si(C CH)2 in 75 ml
of THF, and 9.5 g of MePhSiCl2 in 75 ml of ether.
The mixture was heated for 30 min and then decom-
posed with water and 5% HCl. After conventional
workup and drying over calcined CaCl2, the solvents
were removed at reduced pressure, and the residue
was subjected to high-vacuum distillation (5
10 5 mm) to isolate 0.93 g (5.5%) of compound I.
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Albanov, A.I., Zh. Obshch. Khim., 2000, vol. 70, no. 10,
p. 1650.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 73 No. 10 2003