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Crystal structures of 3/4-pyridyl-based thiosemicarbazones and related Cu and Ni coordination compounds
Tarlok Singh Lobana1, Mani Kaushal1, Robin Bhatia1
1Department of Chemistry, Guru Nanak Dev University, Amritsar 143 005, India.
Abstract:
In this investigation, the crystal structures of the thio-ligands 3-formylpyridine 4-phenylthiosemicarbazone (C13H12N4S, 1) and 4-benzoylpyridine 4-ethylthiosemicarbazone (C15H16N4S, 2), and of two new coordination compounds, chlorido(3-formylpyridine 4-phenylthiosemicarbazone-κS)bis(triphenylphosphane-κP)copper(I) acetonitrile monosolvate, [CuCl(C13H12N4S)(C18H15P)2]·CH3CN, 3, and bis(3-formylpyridine 4-ethylthiosemicarbazonato-κ2N1,S)nickel(II), [Ni(C9H11N4S)2], 4, are reported. In complex 3, the thio-ligand coordinates in a neutral form to the Cu atom through its S-donor atom, and in complex 4, the anionic thio-ligand chelates to the Ni atom through N- and S-donor atoms. The geometry of complex 3 is distorted tetrahedral [bond angles 99.70 (5)-123.23 (5)°], with the P-Cu-P bond angle being the largest, while that of complex 4 is square planar, with trans-S-Ni-S and N-Ni-N bond angles of 180°.
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