Synthesis, Spectroscopy and Thermal-Properties of the Nickel(Ii), Palladium(Ii) and Copper(Ii) Complexes of Bis(Aminoalkyl)- Oxamides (= Lh2) Including the Crystal-Structure of Cu2 L(No3)2

The synthesis of the Ni(II), Pd(II) and Cu(II) complexes of N,N'-bis(aminoalkyl)oxamides (LH2) is described and structures are proposed on the basis of their physical and spectroscopic properties. With Ni(II) and Pd(II) only one complex is formed with general formula NiL or PdL, characterised by coordination through two deprotonated amide N-atoms and two terminal NH2 groups. With Cu(II) it proved possible to obtain three structurally different compounds, depending on the pH, with general formulae Cu(LH2)X2, Cu2(L)X2 and CuL in which X = Cl, Br or NO3. The structure of [Cu2(C8O2N4H16](NO3)2 was solved by means of x-ray diffraction; Mr = 451.33, monoclinic, space group P2(1)/n, a = 9.503(4), b = 7.614(1), c = 10.407(3) angstrom, beta = 98.43(3)-degrees, V = 744.3(7) angstrom 3, Z = 2, Dx = 1.202 g cm-3, mu = 1.33 cm-1, lambda-(MoK-alpha) = 0.71073 angstrom, F(000) = 520, room temperature, R = 0.043, wR = 0.047 for 1080 observed [I greater-than-or-equal-to 3-sigma(I)] not systematically absent reflections out of 1423 measurements and 137 variables. The compound has a conformational chair/boat disorder with 82% in the more stable chair form. Transition Metal Chemistry