Synthesis, crystal structure, thermal studies and antimicrobial activity of a mononuclear Cu(II)-cinnamate complex with N,N,N′,N′-tetramethylethylenediamine as co-ligand

The reaction of copper(II) chloride dihydrate, cinnamic acid and N,N,N',N'-tetramethylethylenediamine afforded a monomeric complex [Cu(tmeda)(cinnamate)(2)]center dot 0.7H(2)O (1) (Where tmeda = N,N,N',N'-tetramethylethylenediamine). The synthesized complex 1 was characterized by means of elemental combustion analysis, thermogravimetric analysis, spectroscopic measurements (UV-Visible, FTIR spectroscopy) and single crystal analysis. The coordination geometry of complex 1 is a distorted octahedron, having cinnamate1 ions coordinated to Cu2+ ion as asymmetric bidentate ligands while N,N,N',N'-tetramethylethylenediamine is coordinated Cu2+ ion in a symmetric bidentate chelating mode, forming a five-membered chelate ring containing copper(II) ion. The crystal lattice in 1 is stabilized by intermolecular O-H center dot center dot center dot O hydrogen bonding interactions. The intermolecular O-H center dot center dot center dot O interactions between lattice H2O molecules and cinnamate groups propagate the monomeric units of complex 1 into 1D-chain motifs. Antimicrobial properties of the complex 1 were evaluated and the results showed that it exhibited remarkable activities against Bacillus spizizenii, and Staphylococcus aureus. A moderate activity against Enterobacter aerogenes, Escherichia coli, Klebsiella pneumonia, and Pseudomonas aeruginosa was observed. No activity was observed against Salmonella enterica, and the fungal strain Aspergillus niger. (C) 2020 Elsevier Ltd. All rights reserved.