Six transition metal–organic materials with the ditopic 4,4′-diaminodiphenylmethane ligand: Synthesis, structure characterization and luminescent properties

Six coordination compounds based on 4,4′-diaminodiphenylmethane (dadpm) and different salts (acetates, nitrates and perchlorates) of four (Ni, Co, Zn, Cd) transition metals have been prepared and characterized by IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction methods. The crystalline solids include four monomers: [Co(dadpm)2(CH3COO)2(H2O)2] (1), [Cd(dadpm)2(CH3COO)2(H2O)2] (2), [Zn(dadpm)4(H2O)2](NO3)2(H2O)2 (3), [Ni(dadpm)3(dmf)(H2O)2](ClO4)2(dadpm)(H2O) (4), and two one-dimensional coordination polymers: {[Cd(dadpm)2(H2O)(ClO4)](ClO4)}n (5) and {[Cd(dadpm)4](ClO4)2}n (6). The transition metals used in this study accommodate two, three, four and six dadpm ligands in the coordination cores. The luminescence properties for six coordination compounds are reported.