RARE EARTH HOMOGENEOUS CATALYSTS FOR RING-OPENING (CO)POLYMERIZATION OF STRAINED-RING OLEFINS

摘要

The organolanthanide hydrides (Cp'2LnH)2 (Cp' = θ5-Me5C5;Ln = Sm,Lu) rapidly catalyze the copolymerization of methylenecyclopropane and ethylene to cleanly yield high molecular weight polyolefins of microstructure {[CH2CH2]x[CH2CH2C(CH2)]y}n via sequential olefin insertion and ring-opening/β-alkyl shift processes. Homopolymerization of methylenecyclopropane likewise cleanly yields polymers of the structure [CH2CH2C(CH2)]n.