Structural and spectroscopic studies on cadmium complex of a biogenic amine, histamine

Abstract

A novel histamine–saccharine complex, [Cd(His) 2(Sac) 2], is investigated by X-ray diffraction, infrared (IR) and electron paramagnetic resonance (EPR) spectroscopies. In the complex, histamine has N τ–H tautomeric form. The crystal packing is stabilized by N–H⋯O hydrogen bonds forming R 2 2 ( 16 ) and R 4 2 ( 4 ) ring patterns. In EPR study, the angular variation of the spectra of Cu 2+ doped Cd(His) 2(Sac) 2 single crystal shows that two different Cu 2+ complexes are located in different chemical environments. Each environment contains one magnetically distinct Cu 2+ site occupying substitutional position in the lattice. The vibrational investigation has been carried out on the basis of some characteristic IR bands of histamine and saccharine molecules.