NEW HOMOCHIRAL ORTHO-PALLADATED MATRIX BEARING A BULKY SUBSTITUENT ATTHE CARBON STEREOCENTER

A new homochiral dimeric ortho-palladated complex bearing a bulky tert -butyl substituent at the carbon stereocenter was synthesized from opt ically active N,N-dimethyl-alpha-tert-butylbenzylamine. Regioselective activation of only the aromatic C-H bond was shown to occur during th e cyclometallation process proceeding under very mild conditions due t o steric effects. Spectral characteristics of mononuclear derivatives of the new dimeric complex indicate that the five-membered palladacycl e exists predominantly in one of two possible chiral conformations wit h the axial position of the tert-butyl substituent.