ASYMMETRIC ACTIVATION OF CHIRAL BINOL-ZIRCONIUM CATALYSTS - EFFECT OFA PRODUCT-LIKE ACTIVATOR

The asymmetric activation of binaphthol (BINOL)-zirconium catalysts is described on the enantioselective allylation of benzaldehyde with all yltin reagents. This model reaction has been used with the intention o f establishing a protocol for a zirconium-based catalyst system, to be followed by structural studies. Initial results are reported that cha racterise a number of interesting features, namely the influence of an induction period and a high level of asymmetric activation obtained a fter addition of a product-like activator. (C) 1998 Wiley-Liss, Inc.