Brooked up! Treatment of (R,Z)-3-(tert-butyldimethylsilyl)-1-cyano-3-hydroxyprop-1-enyl carbamate with a catalytic amount of a base afforded (S,E)-3-(tert-butyldimethylsilyloxy)-1-cyanoallyl diisopropylcarbamate, showing that S(E)2'-type reaction of allylsilicates proceeds in an anti fashion. The overall process is equivalent to trapping of an enantioenriched C-chiral carbanion at the alpha-position of nitrile group in up to 77 % ee (see scheme).
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