Cyclopropanation of styrene with diazoacetates catalyzed by copper and rhodium complexes of new chiral 2,2':6',2-terpyridines derived from natural occurring compounds

Three new chiral 2,2': 6',2-terpyridines (terpy) were prepared from (-)-beta-pinene, (+)-camphor and (+)-2-carene and the corresponding copper and rhodium complexes were assessed as chiral catalysts for the enantioselective cyclopropanation of styrene with diazoacetates. Enantioselectivities up to 64% were obtained. (C) 2002 Elsevier Science B.V. All rights reserved.