Fischer and N-heterocyclic carbene complexes of Group (VII) transition metals

Abstract

The synthetic methodology, structure characteristics and catalytic application of Fischer- and N-heterocyclic carbene (NHCs) complexes of the group VII transition metals were investigated. By using density function theory calculations, the structural and electronic parameters could be elucidated and the fundamental bonding interactions between the carbene ligands and transition metals defined. The bonding definition provided a platform for the comparison of different carbene-metal bonding interactions, an area of research that has been historically misunderstood. Finally, application prospects for both the Fischer- and N-heterocyclic carbene complexes were explored. Both dimetallic Fischer carbene complexes and NHCs containing the cymantrenyl moiety illustrated possible catalytic activity in the dimerization of thiols. Using DFT calculations, the plausible mechanism and energy cycle for the catalytic activity were postulated.