Aminoboranediyl-Bridged Zirconocenes: Highly Active Olefin Polymerization Catalysts

Abstract

Novel aminoboranediyl-bridged zirconocenes [i-Pr2NB(η5-C5H4)2]ZrCl2 (8b) and [i-Pr2NB(η5-1-C9H8)2]ZrCl2 (4b) have been prepared and structurally characterized. When activated by excess methylaluminoxane, 4b and 8b form highly active catalysts for the polymerization of ethylene. The catalyst derived from 4b converts propylene to isotactic polypropylene.