Enantioselectivity in organo transition metal chemistry. An unprecedented ligand effect in π-allyl palladium chemistry

Abstract

In the palladium catalysed allylic alkylation of Schiff bases derived from glycine methyl ester, using Pd-chiral diphosphine ligands, the enantiomeric excess (e.e.) depends upon the proportion of chiral ligand, showing a maximum effect (e.e. up to 62%) for a molar ratio of 2; a 1 : 1 Pd : diphosphine ligand ratio leads to substantially lower e.e. values and reverses the enantioselection.