Dimethylzinc-mediated addition of alkenylzirconocenes to alpha-keto and alpha-imino esters.
[reaction: see text] Hydrozirconation of alkynes followed by in situ transmetalation to dimethylzinc and 1,2-addition to activated ketones and N-diphenylphosphinoylimines leads to tertiary allylic alcohols and amines in high overall yield. With 8-phenylmenthol as the chiral auxiliary, si-face attack proceeds in good to excellent diastereoselectivities.
Wipf
Peter
P
Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA. wipf+@pitt.edu
Stephenson
Corey R J
CR