Structural and spectral studies of nickel(II) complexes with N(4),N(4)-(butane-1,4-diyl) thiosemicarbazones

Abstract Nickel(II) complexes of quinoline-2-carbaldehyde N (4), N (4)-(butane-1,4-diyl) thiosemicarbazone (HL 1 ) and 2-benzoylpyridine N (4), N (4)-(butane-1,4-diyl) thiosemicarbazone (HL 2 ) have been synthesized and physico-chemically characterized by means of partial elemental analyses, molar conductance measurements, magnetic measurements, electronic and infrared spectral studies. Three complexes were given the formulae [Ni(HL 1 ) 2 ]Cl 2 ( 1 ), [Ni(HL 2 )L 2 ]ClO 4  · 7H 2 O ( 2 ) and [NiL 2 Cl] · 0.5H 2 O ( 3 ). The structure of compound 1 has been solved by single crystal X-ray crystallography and is found to be distorted octahedral. Compound 2 , when crystallized in DMSO solution, got deprotonated to form a new compound [Ni(L 2 ) 2 ] ( 2a ), with a distorted octahedral Ni(II) center. In compound 1 , HL 1 coordinates to the metal in the thione form, while in compounds 2a and 3 , HL 2 coordinates in its deprotonated thiolate form.