Enantioselective catalysis of carbonyl-ene and Friedel-Crafts reactions with trifluoropyruvate by 'naked' palladium(II) complexes with SEGPHOS ligands

Chiral dicationic SEGPHOS-Pd(II) complex gives high chemical yield, (E)-olefin selectivity, anti-diastereoselectivity, along with high enantioselectivity even with less reactive mono- and 1,2-disubstituted olefins in this much less reactive ketone-ene reactions. The high levels of enantioselectivity not only in carbonyl-ene but also in Friedel-Crafts reactions stem from the effective shielding with diphenyl groups on phosphines caused by the narrow dihedral angle of metal complexes with SEGPHOS. (C) 2004 Elsevier Ltd. All rights reserved.