Two new copper (II) carboxylate complexes based on N,N,N′,N′-tetramethylethyleneamine: Synthesis, crystal structures, spectral properties, dft studies and hirshfeld surface analysis

In this study, two new copper (II) carboxylate complexes, [Cu(4-mba)(2) (tmeda)](1) and [Cu(3mba)(2)(H2O)(2)(tmeda)](2) (4-mbaH = 4-methylbenzoic acid, 3-mbaH = 3-methylbenzoic acid, tmeda = N,N,N',N'-tetramethylethyleneamine) were synthesized. The structures and properties of the complexes were determined by X-ray single crystal diffraction method and FT-IR spectroscopy. While the crystal packing of the complex 1 is stabilized by C-H center dot center dot center dot O hydrogen bonds, in the complex 2, the molecules are connected to each other by C-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonds. The optimized structures were formed using density functional theory (DFT) at the B3LYP level within the 6-311G(d,p) and LAN2DZ basis sets. Their Hirshfeld surface analyses were performed for the detailed investigation of all the contacts involved in the crystal packing. 2D fingerprint plots and Hirshfeld surface analyses signify important interactions in the crystal packing [H center dot center dot center dot H (64.2%), C center dot center dot center dot H/H center dot center dot center dot C (21.1%) and O center dot center dot center dot H/H center dot center dot center dot O (14.7%) contacts for [Cu(4-mba) 2(tmeda)], while [Cu(3-mba)(2)(H2O)(2)(tmeda)] showed H center dot center dot center dot H (67.3%), C center dot center dot center dot H/H center dot center dot center dot C (21.8%) and O center dot center dot center dot H/H center dot center dot center dot O (10.9%) contacts]. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Two new copper (II) carboxylate complexes, [Cu(4-mba)(2)(tmeda)] and [Cu(3mba)(2)(H2O)(2)(tmeda)], were synthesized and their structures and properties were determined by X-ray single crystal diffraction method and FT-IR spectroscopy. The crystal packing of the complexes involved C-H···O and O-H···O hydrogen bonds, with detailed analyses conducted using density functional theory at the B3LYP level. Hirshfeld surface analyses revealed significant interactions in the crystal packing, with different contacts observed for each complex.