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Crystal structure of di-aqua-bis-(N,N-di-ethyl-nicotinamide-κN (1))bis-(2,4,6-tri-methyl-benzoato-κO (1))cobalt(II)
Gülçin Şefiye Aşkın1, Hacali Necefoğlu2, Safiye Özkaya3
1Department of Physics, Hacettepe University, 06800 Beytepe, Ankara, Turkey.
Abstract:
The centrosymmetric mol-ecule in the monomeric title cobalt complex, [Co(C10H11O2)2(C10H14N2O)2(H2O)2], contains two water mol-ecules, two 2,4,6-tri-methyl-benzoate (TMB) ligands and two di-ethyl-nicotinamide (DENA) ligands. All ligands coordinate to the Co(II) atom in a monodentate fashion. The four O atoms around the Co(II) atom form a slightly distorted square-planar arrangement, with the distorted octa-hedral coordination sphere completed by two pyridine N atoms of the DENA ligands. The dihedral angle between the planar carboxyl-ate group and the adjacent benzene ring is 84.2 (4)°, while the benzene and pyridine rings are oriented at a dihedral angle of 38.87 (10)°. The water mol-ecules exhibit both intra-molecular (to the non-coordinating carboxyl-ate O atom) and inter-molecular (to the amide carbonyl O atom) O-H⋯O hydrogen bonds. The latter lead to the formation of layers parallel to (100), enclosing R 4 (4)(32) ring motifs. These layers are further linked via weak C-H⋯O hydrogen bonds, resulting in a three-dimensional network. One of the two ethyl groups of the DENA ligand is disordered over two sets of sites with an occupancy ratio of 0.490 (13):0.510 (13).
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