Synthesis and characterization of [M^II(bqb)] (M = Co, Ni, Cu), [N(n-Bu)₄][Co^III(bqb)(CN)₂], and [N(n-Bu)₄][Co^III(bqb)(N₃)₂] containing deprotonated N,N'-bis(2-quinolinecarboxamide)-1,2-benzene (bqb) – X-ray crystal structures of [Ni^II(bqb)] and [N(n-Bu)₄][Co^III(bqb)(N₃)₂]

Cobalt(II), nickel(II), copper(II), and two cobalt(III) complexes of a new dianionic ligand, bqb, [H(2)bqb = N,N'-bis(2-quinolinecarboxamide)-1,2-benzene] have been synthesized and characterized by elemental analyses, IR, and H-1 NMR spectroscopy. The crystal and molecular structures of the [Ni(bqb)] (2) and [N(n-Bu)(4)][Co-III(bqb)(N-3)(2)] (5) complexes were determined by X-ray crystallography. Complex 2 crystallizes in the monoclinic space group C2/c with a distorted square-planar structure including two short Ni-N (1.848 angstrom) and two long Ni-N (1.958 angstrom) bonds. The structure consists of sheets formed in the plane parallel to the b axis and diagonal to vectors a and c by intermolecular hydrogen bonds. Complex 5 crystallizes in the monoclinic space group C2 with a distorted octahedral structure. The [N(n-Bu)(4)](+) ion is disordered at the C3A and C4A atoms of one Bu. The IR and H-1 NMR spectra of the complexes are also discussed.