Ethylene polymerization and ring-opening metathesis polymerization of norbornene catalyzed by (arylimido)(aryloxy)vanadium(V) complexes of the type, V(NAr)(OAr′)X2 (X = Cl, CH2Ph)

VCl2(N-2,6-Me2C6H3)(O-2,6-(Pr2C6H3)-Pr-i) - methylaluminoxane catalyst has exhibited remarkable catalytic activity for ethylene polymerization. High molecular weight ring-opened poly(norbornene) has been prepared in the presence of V(CH2Ph)(2)(N-2,6-Me2C6H3)(O-2,6-(Pr2C6H3)-Pr-i).