Coinage Metal-N-Heterocyclic Carbene Complexes

N-heterocyclic carbene (NHC) contains a carbene carbon incorporated in a nitrogen containing heterocycle, which is reactive and difficult to isolate. An enormous amount of research work has been performed on this coinage metal due to the rapid development of various new chemistries, especially in catalysis. Many complexes with C,Y-chelating NHCs, where Y is a hetero donor atom, have been successfully prepared. The retention of chirality during the entire process is a great property to this technique. Considerable effort has been devoted to find new therapeutic uses of silver and gold compounds. The advantage of Ag(I)-NHCs over other silver compounds as antimicrobial agents for wound healing has been reported. This was attributed to their stability in water, which allowed for the slow release of Ag(I). The influence of substituent change on the steric and the electronic properties of coinage metal-NHCs is not well understood, and further work is needed.