Creatinine complexes of zinc,cadmium and mercury

Zinc, cadmium and mercury(II) complexes of creatinine of the composition M(Creat)₂X₂ (X = Cl, Br or I) are prepared. The complexes are characterized by analytical and spectral methods. The increase in cyclic NH stretching frequency in the case of complexes (3350 cm^?1) from that of the free ligand (3300 cm^?1) suggested that secondary nitrogen is involved in coordination. The shift in the resonances of cyclic NH proton in the ¹H NMR and carbonyl and imine carbons in ¹³C NMR when compared to the ligand indicated that cyclic nitrogen coordinates. Conductivity measurements in N, N-dimethylformamide suggested that the complexes are non-electrolytes. Thermal decomposition behaviour of the complexes is also discussed.