Molecular structures of some bivalent metal complexes of 1-(4-acetylphenyl)imidazole and co-ligands

A series of bivalent metal complexes having compositions [Co(L)(2)Cl-2] (1), [Zn(L)(2)Cl-2] (2), [Co(L)(2)(H2O)(4)](NO3)2.2H(2)O (3), [Zn(L)(2)(H2O)(4)](NO3)(2).2H(2)O (4), [Co(L)(2)(OAc)(2)(H2O)].3H(2)O (5), [Mn(L)(2)(OAc)(2)(H2O)].3H(2)O (6) [Co(L)(4)(NCS)(2)] (7), {[Co(L)(2)(Fum)(H2O)(2)].2H(2)O}n (8) and {[Mn(L)(2)(Fum)]}(n) (9) were synthesized using L {L=1-(4-acetylphenyl)imidazole} and respective co-ligands. The mononuclear sets 12, 34 and 56 are isomorphous and isostructural in nature. Complex 7 is a mononuclear complex, 8 is a 1D coordination polymer and 9 is a 2D-coordination polymer. All the compounds were structurally characterized using IR spectroscopy, thermogravimetric analyses, powder X-ray and single crystal X-ray diffraction studies. In general, coordinated/lattice water molecules are found to be involved in O-H...O hydrogen bonding and counter ions, in other weak interactions like C-H...S, C-H...Cl and C-H...O. The aromatic ring of L also is involved in C-H...pi and pi...pi stacking interactions. In 3 and 4, hydrogen bonding interactions between coordinated water molecules, lattice water and nitrate ion contain cyclic hydrogen-bonded architectures. In 5 and 6, acetyl group present in L act as hydrogen bond acceptor through OHO interaction. In 8 and 9 Fum coordinate to metal center in mu-eta(1):eta(1) bidentate and mu(4)-eta(1):eta(1):eta(1):eta(1) tetradentate fashions resulting in formation of 1D and 2D coordination polymers, respectively. (C) 2018 Elsevier Ltd. All rights reserved.