Ni(II) complexes with optically active bis(menthane), pinano-para-menthane ethylenediaminodioximes and pinano-para-menthane, bis(pinane) propylenediaminodioximes:: Synthesis, structures, and properties

Reactions of Ni(NO3)(2) center dot 6H(2)O) in EtOH(iso-PrOH) with optically active bis(menthane) ethylenediaminodioxime (H2L1), pinano-para-menthane ethylenediaminodioxime (H2L2), pinano-para-menthane propylenediaminodioxime (H2L3) and bis(pinane) propylenediaminodioxime (H2L4) were used to synthesize [Ni(H2L1)NO3]NP3 center dot 2H(2)O (I), [Ni(HL2)]NO3 (II), [Ni(HL3)]NO3 (III), and [Ni(HL4)]NO3 (IV). X-ray diffraction study of paramagnetic complex I (mu(eff) = 3.04 mu B and diamagnetic complexes II and III revealed their ionic structures. A distorted octahedral polyhedron N4O2 in the cation of complex I is formed by the N atoms of tetradentate cycle-forming ligand, i.e., the H2L1 molecule, and the O atoms of the NO3- anion acting as a bidentate cyclic ligand. In the cations of complexes H and III, containing a pinane fragment, the coordination core NiN4 has the shape of a distorted square formed on coordination of tetradentate cycle-forming ligands, i.e., anions of the starting dioximes. The structure of diamagnetic complex IV is likely to be similar to the structures of complexes II and III.