The rate of hydrolysis–condensation reaction of phenyltrichlorosilane in water-acetone solutions and the product yields were shown to significantly depend on the concentration of HCl (C
HCl) in the solutions. The main product of the reaction was all-
cis-(tetrahydroxy)(tetraphenyl)cyclotetrasiloxane. This was different
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The rate of hydrolysis–condensation reaction of phenyltrichlorosilane in water-acetone solutions and the product yields were shown to significantly depend on the concentration of HCl (C
HCl) in the solutions. The main product of the reaction was all-
cis-(tetrahydroxy)(tetraphenyl)cyclotetrasiloxane. This was different from the earlier published results of analogous reactions of
m-tolylSiCl
3,
m-ClPhSiCl
3, and
α-naphtylSiCl, in which some products of other types were formed. For example,
trans-1,1,3,3-tetrahydroxy-1,3-di-
α-naphtyldisiloxane was obtained in the case of
α-naphtylSiCl
3. All-
cis-(tetrahydroxy)(tetraphenyl)cyclotetrasiloxane was treated in acetone with HCl to give the other three geometric isomers (
cis-cis-trans-,
cis-trans-, and all-
trans-). The thermal self-condensation of these four isomers under “pseudo”-equilibrium conditions (under atmospheric pressure) was investigated in different solvents, in quartz or molybdenum glass flasks. The compositions of the products were monitored by APCI-MS and
29Si NMR spectroscopy. It was shown that all-
cis- and
cis-cis-trans-isomers in toluene or anisole mostly gave the cage-like Ph-T
8,10,12,14 and uncompleted cage-like Ph-T
10,12OSi(HO)Ph compounds. In contrast to these two isomers, the
cis-trans–isomer in toluene mainly formed dimers with the loss of one or two molecules of water. However, in acetonitrile, significant amounts of Ph-T
10,12 and Ph-T
10,12OSi(HO)Ph species were formed along with the dimers. All-
trans-isomer did not enter into the reaction at all.
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