Synthesis and structure of optically active compounds [Ni(HL1)]NO3 and [Ni(HL2)]NO3?H2O containing anions of diaminodioximes H2L1 and H2L2 derived from ?-pinene and (+)-3-carene as ligands

Abstract

New optically active levorotatory compounds [ Ni ( HL 1 )] NO 3 ( I ) and [ Ni ( HL 2 )] NO 3 · H 2 O ( II ) containing the anions of chiral diaminodioximes, H 2 L 1 and H 2 L 2 , derived from the terpenes α -pinene and (+)-3-carene, respectively, were synthesized. Complexes I and II were studied by X-ray diffraction. The crystal structures of compounds are ionic, being composed of the [ Ni ( HL 1 )] + or [ Ni ( HL 2 )] + cations and the outer-sphere N anions. The Ni 2+ ion coordinates four N atoms of the tetradentate chelating ligand, the NiN 4 coordination unit being shaped like a tetrahedrally distorted square. Compounds I and II are diamagnetic, which corresponds to a low-spin d 8 configuration. The NMR spectra of compounds were recorded and analyzed. O 3 -