In the present inquisition, the reaction of N 2 with four principal carbenes(1 R , 2 R , 3 Therefore, the further quest was continued. A set of new carbenes (5 R , R = CF 3 , CN , H, M e, OM e, P h, tBu) analogous to carbene 1 R , are also exploited for the fixation of nitrogen (Sec. 3.2). It is noticed that 5 CN is an affluent candidate for N 2 activation. However, the Gibbs' free energy change for the formation of 5B CN remains positive. Thus, further explorations were demanded which were fulfilled by the reduction of diazo derivative by hydrogen, formation of azo derivative and mutation at the heteroatom of the carbene (Sec.