Syntheses, Spectra, Thermal Studies and Crystal Structures of Vitamin B13 Complexes of Nickel(II) with N,N,N′,N′-Tetramethylethylenediamine and 2,2-Dimethylpropane

Abstract

Two nickel(II) complexes of vitamin B13 (H<inf>3</inf>Or) with N,N,N′,N′-tetramethylethylenediamine (tmen) and 2,2-dimethylpropane- 1,3-diamine (dmpen) were synthesized and characterized by means of elemental and thermal analyses, magnetic susceptibility, and IR and UV/Vis spectroscopic studies. The crystal structures of mer-[Ni(HOr)(H<inf>2</inf>O) <inf>2</inf>(tmen)]·H<inf>2</inf>O (1) and [Ni(HOr)-(dmpen)<inf>2</inf>] (2) were determined by using single-crystal X-ray diffraction. In the complexes, which crystallize in the triclinic system (space group P1̄ for 1) and the monoclinic system (space group P2<inf>1</inf>/c for 2), the NiII ions exhibit a distorted octahedral coordination. NiII ions are chelated by the deprotonated nitrogen atom of the pyrimidine ring and the oxygen atom of the carboxylate group, the distorted octahedral coordination completed by one tmen and two aqua ligands for 1 or two dmpen ligands for 2. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.