Phospholane-phosphite ligands for Rh catalyzed enantioselective conjugate addition : unusually reactive catalysts for challenging couplings

Abstract

The use of Rh catalysts derived from a phospholane-phosphite ligand were found to be more productive than the classic rhodium/BINAP system in enantioselective conjugate additions. These catalysts enable the use of lower amounts of aryl boronic acid in an asymmetric arylation reaction that required an impractical excess of nucleophile. This catalyst was also found to enable the coupling of a poorly reactive Michael acceptor, N-CBz-2-3-dehydro-4-piperidone, or the coupling of poorly reactive 2-furyl boronic acids at ambient or near temperatures.