Cyanide bridged trinuclear complexes with central metals bearing pyridine ring ligands

Starting from Fe, Mn, Co and Ni precursors with Py, Bpy and Phen ligands 31 new trinuclear cyanide bridged complexes were obtained, in which the units (CO)5Cr–CN, (CO)5Mo–CN, (CO)5W–CN, Cp(CO)2Fe–CN, Cp(dppe)Fe–CN and Cp(PPh3)2Ru–CN occupy the external positions. Structure determinations showed that the central metals display cis- and trans-octahedral as well as tetrahedral MLn(NC–M′)2 coordinations. From the ν(CN) bands in the IR spectra and from the redox potentials of the external organometallic units it can be concluded that the central complex units are electron sinks. This property prevents electronic communication between the two external metal centers.