Regio- and stereospecific cleavage of silyl- and disilylepoxides with lithium diphenylphosphide.

Unsubstituted or alpha- and beta-C-substituted silylepoxides react stereospecifically with lithium diphenylphosphide, optionally followed by methylation, to give vinylphosphonium iodides or vinylphosphine oxides resulting from alpha-opening and silyl enol ethers, vinylsilanes or alpha-hydroxysilanes by beta-opening. On the other hand, alpha,beta- or alpha,alpha-disilylepoxides afforded beta-silyl vinylphosphine oxides or alpha-silylated silyl enol ethers by alpha- and beta-cleavage, respectively. All compounds are interesting synthons in organic chemistry.

Regiospecific and stereoselective synthesis of functionalized and differently metalated alkenes by silyl- or stannylcupration of metalated acetylenes.

Differently metalated vinylcuprate intermediates resulting from silyl- or stannylcupration of silyl- and tin-containing acetylenes reacted with a range of electrophiles, including chlorosilanes and chlorostannanes, affording regio- and stereodefined differently metalated vic and gem silyl- and tin-trisubstituted alkenes. Some of these functionalized polymetalated olefins are interesting synthons in organic chemistry.