Recent Progress of N-Heterocyclic Carbene Complexes Synthesized by Poly-imidazolium Salts

Abstract Owing to the excellent chemical stability and catalytic activity, N-heterocyclic carbene (NHC) complexes have always been the hotspot in the field of organic chemistry. Imidazolium salts are the precursors of NHCs, and their easy preparation and structure diversity properties make them useful for the generation of NHC complexes with topology structures. In this paper, the recent progress of synthesis, structure and physicochemical properties of NHC complexes with cylindrical, cage-like, macrocyclic, square and rectangular molecular structures which are synthesized by poly-imidazolium salts is summarized and reviewed.