Synthesis of vanadium–alkylidene complexes and their use as catalysts for ring opening metathesis polymerization

Abstract

Reported examples for synthesis of vanadium–alkylidene complexes and some selected reactions have been summarized. (Imido)vanadium(V)–alkylidene complexes exhibit catalytic activities for ring-opening metathesis polymerization (ROMP) of cyclic olefins; V(CHSiMe₃)(N-2,6-Cl₂C₆H₃)(OC₆F₅)(PMe₃)₂ exhibited remarkable catalytic activities for ROMPs of norbornene derivatives, polymerized cyclopentene and cis-cyclooctene. Highly cis-specific (living) ROMPs of norbornene have been achieved by V(CHSiMe₃)(N-2,6-X₂C₆H₃)[OC(CF₃)₃](PMe₃)₂ (X = H, Cl), and the activity increased at high temperature (50 and 80 °C) without a decrease in cis specificity (98%) in the presence of PMe₃.