N-Heterocyclic carbenes: application of ruthenium–alkylidene complexes in ring-opening metathesis polymerization

Abstract

Novel ruthenium–alkylidene catalysts bearing N-heterocyclic carbenes were applied in ring-opening metathesic polymerization (ROMP) reactions of various norbornene derivatives. High tolerance towards polar functional groups as well as high catalytic activity is demonstrated. The combination of N-heterocyclic carbenes and coordinatively labile ligands (phosphanes or chloro-bridged transition metals) on the ruthenium center proves not only successful regarding catalytic performance but also promising with respect to polymer properties.