Donor complexes of bis(1-indenyl)phenylborane dichlorozirconium as isospecific catalysts in propane polymerization

Chiral boron-bridged ansa-type zirconocenes can be prepared in a few simple steps; various donor molecules such as Et2O, THF or PMe3 undergo complexat ion at boron leading to catalysts having vastly different catalytic propert ies in Ziegler-Natta polymerization of propene; the PMe3-containing catalys t is the most active and stereoselective (96% isotacticity).