Properties and Reactions of Intramolecularly Activated Alkenylsilanes, Alkenylgermanes

2 Properties and Reactions of Intramolecularly Activated Alkenylsilanes, Alkenylgermanes 

The importance of the torquoselective olefination is illustrated in Fig. 34 for the particular case in which a multisubstituted alkenylsilane is converted to various kinds of multisubstituted olefins. The silyl-substituted allyl alcohol 93 is allylated to give the 1,4-diene 94, and the iodoalkene 95, prepared by desilyliodination of 93, is subjected to palladium-catalyzed cross-coupling reactions (the Heck reaction, Stille coupling) to afford the dienes 96 and 97 without ElZ isomerization. 

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