Pure Appl. Chem., 2007, Vol. 79, No. 9, pp. 1481-1489
http://dx.doi.org/10.1351/pac200779091481
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.
Keywords
aqueous medium; asymmetric; catalysis; immobilization; palladium; polymer support.