Silylmercurials reactions with

The silylmercury compounds are most conveniently available by reacting a chlorosilane with sodium amalgam. In contrast to the two methods mentioned above, which in most cases require polar, aprotic solvents such as THF, DME or HMPA, transmetalation reactions can be performed in nonpolar solvents and often result in better yields than when performed in ethereal solvents. 

Transmetallation of silylmercury compounds, which are most easily available via the reaction of a silane with (/-Bu)2llg, appears to be the most convenient method for the preparation of cyclic potassium oligosilyl compounds c-(MegSis)K (19)83c as well as c-(MenSi6)K (20)84 were obtained by Hengge and coworkers from the corresponding mercury compound by means of a Na/K alloy in THF (equation 33). 

Doubtless, in these reactions unstable intermediate silylmercury compounds such as [H2(CH3)Si]2Hg and [H(CH3)2Si]2Hg are first produced which then undergo decomposition. The formation of the trisilane and higher polysilanes from the reaction of (CH3)2SiHBr with Na/Hg may be rationalized by the insertion into [H(CH3)2Si]2Hg of dimethylsilylene, (CH3)2Si , which is probably produced during the reaction through decomposition of an unstable intermediate species (CH3)2SiHg, followed by decomposition of the adducts. The generation of dimethylsilylene and its insertion into the... 

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. 

Unsymmetrical silylmercurials can be cleaved with formation of a second Si—Hg bond these reactions are followed by a disproportionation step ... 

Anionic silylmercurials (see 5.7.3.1) are also formed by the reaction of (EtjS jHg with KCN in the presence of crown ethers, the products being Et3SiCN and K3[Hg(SiEt3)J. 

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