Etude de la régiosélectivité de l'action des organozinciques sur les α-iminoesters: synthèse d'α-aminoesters C-substitués par un groupe α-insaturé ou α-fonctionnel

C- and N-Selective Grignard Addition Reactions of α-Aldimino Esters in the Presence or Absence of Zinc(II) Chloride: Synthetic Applications to Optically Active Azacycles

Highly practical synthetic methods were developed for the C- and N-selective Grignard addition reactions of N-4-MeOC6H4-protected α-aldimino esters in the presence or absence of zinc(II) chloride. Diastereoselective C-alkyl addition, tandem C-alkyl addition-N-alkylation, and some transformations to synthetically useful optically active azacycles were demonstrated.

Synthesis of Homoallylic Amines by Hydrozirconation−Imine Addition of Allenes

Hydrozirconation of allenes followed by in situ transmetalation to dialkylzinc leads to the formation of an allylic zinc species that, upon addition of aldimines to the reaction mixture, provides homoallylic amines in 64-85% yield. [reaction: see text]

The direct α-zincation of amides, phosphonates and phosphine oxides by H–Zn exchange

Stoichiometric or catalytic quantities of simple 2 degrees amines greatly increase the rate of H-Zn exchange between ZnPh2 and a range of relatively non-acidic substrates, allowing for the convenient and direct preparation of alpha-functionalized organozincs.