Alkyl-substituted oxamide oximes and their metal complexes

Nickel(11) and palladium(II) complexes of oxamide oximes substituted with alkyl chains of different length (CnH2n+1, n = 4, 6, 8, 10, 12 and 16) have been synthesized from the reaction of (E,E)-monochloroglyoxime with the corresponding amine derivatives. The Ni(II) and Pd(11) complexes have been prepared by reacting the ligand with either NiCl2 center dot 6H(2)O or Na2PdCl4 in ethanol. All the compounds were characterized by elemental analyses, H-1 NMR, IR and mass spectra. The molecular structure of bis[(N-hexylaminoglyoxime)]palladium(II) (2b) was obtained by single crystal X-ray diffraction and it was found to be centrosymmetric at the metal center, which is bound by the four oximic nitrogen atoms of two ligands in a square planar environment. The role of the H-bonding in the structures of these complexes was investigated. (C) 2011 Elsevier Ltd. All rights reserved.