Synthesis and Crystal Structure of Hexakis(imidazole) nickel (II) O,O′-diphenyldithiophosphate [Ni(Im)6](Ph2O2PS2)2
The crystal and molecular structures of [Ni(Im)6](dtp)2 (Im = imidazole, dtp = O,O′-diphenyldithiophosphate) have been determined by X-ray crystallography. It crystallizes in the triclinic system, space group Pī, with cell parameters a = 9.375 (2), b = 12.324(3), c = 13.285(3) Å, α = 107.86(3), β = 102.28(3), γ = 109.24(3), and Z = 1. The crystal structure of the title compound is built up of discrete monomeric molecules of [Ni(Im)6](dtp)2. The nickel (II) ion is hexacoordinated by six imidazole molecules and the coordination environment of Ni (II) is of octahedral geometry. In the solid state, a network of N-H∙∙∙S intermolecular hydrogen bonds connect the Ni(Im)6 moieties and O,O′-diphenyl- dithiophosphate molecules, forming a three-dimensional structure.
Mercury(II) Complexes of Imidazole and Histidine
NORMAN DAVIDSON Vol. 82 The absorption band of medium intensity at 1308 cm.-' in the reagent, which is also probably due to C-0 vibrations, is affected to a small extent in the case of Pb(I1) and Cd(I1) chelates but is shifted to a marked degree in the chelates of the transition metals. This implies that the C-0 group vibrations in the metal chelates of 4-hydroxybenzothiazole are influenced to a slight extent by the mass of the metal in the chelate ring. The interaction of the C-0 group with the n-bonds in the chelate ring as well as with the d- electrons of the metal atoms play a much more important part in determining the extent of the shifts that are observed in C-0 group vibra- tions as we go from the reagent to the metal chelates. It was found that if the frequency of band that appears between 1310 and 13% an.-' for the transition metal chelates of 4-hydroxybenzo- thiazole was plotted against the stability constant (log &) of the chelate, a linear relationship was ob- tained. This type of relationship has been found in a number of metal c~mplexes'~~'~ and confirms the assignments made for the C-0 vibrations in the 4-hydroxybenzothiazole chelates. Acknowledgment.-The authors are grateful for a grant from the
PREPARATION AND CHARACTERIZATION OF SOME BINARY AND TERNARY METAL COMPLEXES OF IMIDAZOLE AND AMINO ACIDS
Five new ternary metal complexes containing imidazole and glycylglycine or amino acid have been prepared and characterized by proton magnetic resonance and infrared spectral studies. Seven new bina...