Development of praline derived chiral aminophosphine ligands for palladium -catalyzed asymmetric allylic alkylation

Abstract

A series of chiral aminophosphine ligands with N, N-disubstituted 2-diphenylphosphinoaniline backbone are designed and readily prepared from (R)-2-(methoxymethyl)pyrrolidine or (S)-prolinol. The reactivity and selectivity in the palladium-catalyzed asymmetric allylic alkylation (AAA reaction) of 1,3-diphenyl-2-propenyl acetate with a dimethyl malonate-BSA-LiOAc system using these chiral ligands are evaluated. Furthermore, chiral fluorous aminophosphine bearing two fluo rous ponytails was prepared from (S)-prolinol. Chiral fluorous palladium catalyst from this ligand was easily reused in palladium-catalyzed AAA reaction with good enantipselectivity.