Silicon silylmercurials

Enantiomeric silylmercury compounds are obtained from reaction of diorganomercurys with an optically active hydrosilane [Eq. (6)] (76). The configuration is retained predominantly at silicon. These compounds, however, racemized readily when sublimed during purification. 

Several dimerization rates of alkyl-substituted silyl radicals were measured earlier [8]. However, the dimerization rates of silyl-substituted silicon-centered radicals have not previously been determined. In this study we have measured, using EPR spectroscopy, the rate constants for the recombination of four silyl radicals (lb, 2b, 3b, and 4b), to produce the corresponding disilane dimers of type a (i.e. la, 2a, 3a, and 4a respectively). This dimerization reaction is shown as the backward reaction of Eq. 2 in Scheme 1. Radicals lb, 2b, and 3b were generated photochemically fiom the corresponding disilane dimers of type a (Scheme 1, Eq. 2), while radical 4b was generated photochemically from the corresponding silylmercury compound 4c (Scheme 1, Eq. 1). 

Most isolable silylmercury compounds have three organic groups bonded to silicon, but the formation of H3SiHg derivatives is achieved by ... 

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