Asymmetric Deprotonation−Substitution of <i>N</i>-Pop-benzylamines Using [RLi/(−)-Sparteine]. Enantioselective Sequential Reactions and Synthesis of N-Heterocycles
Pop-directed asymmetric deprotonation of benzylic amines using [n-BuLi/(-)-sparteine] provides an efficient method for the synthesis of chiral NC alpha and NC alpha,alpha' derivatives with total selectivity with respect to competing allylic and ortho lithiation. The method described herein offers a straightforward route of accessing chiral N-Pop-protected nitrogen heterocycles.