Asymmetric allylic substitution of cycloalkenyl esters in water with an amphiphilic resin-supported chiral palladium complex

Abstract

A novel homochiral phosphine ligand, (3R,9aS)[2-aryl-3-(2- diphenylphosphino)-phenyl]tetrahydro-1H-imidazo[1,5-a]indole-1-one, was designed, prepared, and anchored onto an amphiphilic polystyrene-poly(ethylene glycol) copolymer (PS-PEG) resin. Catalytic asymmetric substitution of a racemic mixture of cycloalkenyl esters with carbon, nitrogen, and oxygen nucleophiles was achieved in water as the single reaction medium under heterogeneous conditions by using the PS-PEG resin-supported palladium-imidazoindole phosphine complex to give optically active substituted cycloalkenes with up to 99 % ee. © 2007 IUPAC.