Based on Deprotonation of Selenoketals and Seleno-orthoesters

Applications Based on Deprotonation of Selenoketals R Se CHB — alkyl) and Seleno-orthoesters. Deprotonation, usually with KDA, of selenoketals (PhSe)2CHR (R = alkyl) gives carbanions that react efficiently with common electrophiles [primary alkyP - and benzyl halides, aldehydes, ketones, and (for R = alkyl or H) epoxides ]. A few of the resulting selenoketals have been hydrolysed under very mild conditions. Carbanions derived from selenoketals undergo intramolecular reactions [e.g. (49)] when appropriately substituted, and can be used in the synthesis of silyl enol ethers, e.g. (50).  

The orthoester (MeSe)3CH gives, with LDA, the salt (MeSe)3CLi, whose reactions with alkyl halides, epoxides, and heptanaP have been demonstrated. 

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