Research Activities & About the Group
Transition metals complexes of N-heterocyclic carbene (NHC) ligands have been become increasingly important candidates as catalysts, metal-based drugs and as fluorescent materials. NHCs can be prepared by deprotonation of an acidic proton from an N-heterocyclic system such as a benzimidazolium or an imidazolium ion. The significance of NHCs in organometallic chemistry was originally recognized in 1968, however, no significant interest was given to this field until the isolation of the first free carbene in 1991. Later, importance of these NHCs as strong sigma-donor and weak pi-acceptor ligands in organometallic chemistry was evidenced.
NHCs have been complexed with almost every transition and many s-block metals through sigma-donation of the carbene lone pair electrons. NHC ligands are also useful as alternatives to phosphines as the bond strength of carbene carbon and metal centre is comparable with the bond strength of phosphorous and metal bond. This has been especially, increased the interest in this field to synthesize NHC complexes of phosphine analogues and evaluation of their catalytic properties. Our research work currently is on design, synthesis and characterization of transition metal complexes of NHCs. Our laboratory is fully equipped for synthetic work. Our focus is oriented towards design and synthesis of silver(I)-, palladium(II)- and gold(I/III)-NHC complexes. For characterizations, we routinely use NMR, FTIR, UV-vis and MS spectroscopies and analytical techniques such as CHN microanalysis and single crystal XRD.
Based on the applicability of the transition metal-NHC, research in the following four broad areas are being carried out.