Strong electron-donating metalla-N-heterocyclic carbenes†
Abstract
By choosing the appropriate coupling reactions an isocyanide ligand in complex [Fe(Cp)(CO)(CNxylyl)2]+ is transformed into either a conventional NHC or into a metalla-N-heterocyclic carbene (MNHC), with the stretching frequencies of the CO and CNR ligands attached to the iron center demonstrating the stronger electron-donating ability of the metal-containing carbenes.