Alkene oligomerisation and polymerisation with metal-NHC based catalysts

Metal complexes of N-heterocyclic carbenes (NHCs) are now ubiquitous in homogeneous catalysis, yet their use as catalysts for oligomerisation and polymerisation of alkenes is only now gaining momentum. In recent years, a range of NHC complexes from across the transition series, and from the lanthanides, have been tested as alkene polymerisation catalysts with varying results. This perspective details the research in this field since 1998, when metal-NHC complexes were first tested for alkene polymerisation.