SYNTHESIS, STRUCTURE AND H-1-NMR SPECTRA OF CADMIUM COMPLEXES WITH 2,6-BIS(BENZIMIDAZOL-2'-YL)PYRIDINE

The cadmium complexes with the formulae CdLX2.nH2O (X = Cl-, n = 1; X = NO3-, n = 0.5), Cd(L-H)LX (X = ClO4-, BF4-) and Cd(L-H)Ac, where L is 2,6-bis(benzimidazol-2'-yl)pyridine, were obtained by reactions of L with different cadmium salts in methanol and characterized by elemental analysis, electrical conductance, IR and H-1 NMR spectra. It has been found also that in the perchlorate, acetate and tetrafluoroborate complexes the ligand loses an N-proton on the benzimidazole ring of the ligand, acting as a singly negative ligand. The neutral complex Cd(L-H)2 was also first structurally characterized. The geometry about cadmium is a distorted octahedron with six nitrogen atoms from two singly negative tridentate ligands.