The amino group of natural L-amino acid esters is protected by condensation with 2- oxocyclopentanenitrile (1) or 2-formyl-2-pheny~ dtetonitrik (10). Only the ester group of the formed cyanoenamino esters 2 and 11 reacts with nucleophilic reagent!; such as organometallics (RMgX, RLi), borohydrides, or metal amides, whereas the cyanoenamino group is unchanged (Schemes I and 2). Cyanoenamino alcohols obtained by reduction of ...
