Highly enantioenriched homoenolate reagents by asymmetric γ-deprotonation of achiral 1-silyl-substituted 1-alkenyl carbamates
1-Trimethylsilyl-1-alkenyl carbamates 1 are deprotonated by n-butyllithium/(-)-sparteine (2) with a high degree of enantiotopic differentiation in the γ-position to form the enantiomerically enriched allyllithium derivatives 3. Trapping these with several