Structures with different supramolecular interactions and spectral properties of monomeric, dimeric and polymeric benzoatocopper(II) complexes

摘要

Three new monomeric benzoatocopper(II) complexes [Cu(3-MeObz)(2)(4-PM)(2)] (1), [Cu(3-Mebz)(2)(4-PM)(2)] (2) and [Cu(4-mebz)2(4-PM)(2)] (3), two polymers [Cu-2(2-Mebz)(4)(4-PM)](n) (4) and [Cu-2(3-Mebz)(4)(4-PM)](n) (5), and the dimeric complex [Cu-2(2-Fbz)(4)(4-PM)(2)] (6) (where 4-PM = 4-pyridylmethanol, 2-Fbz = 2-fluorobenzoate anion, 3-MeObz = 3-methoxy-benzoate anion and x-Mebz = 2-,3- or 4-methylbenzoate) have been synthesized and characterized by elemental analysis as well as by single-crystal diffraction. All the complexes have been studied by infrared, UV-vis and EPR spectroscopy. The neutral ligand 4-PM acts as a terminal ligand in 1-3 and 6, and as a bridging ligand in 4 and 5. The structural motives are evident in the EPR spectra, which have shown axial symmetric features for 1-3, whilst the polymers as well as the dimer (4-6) have exhibited an acetate-type feature. The monomeric complex molecules of 1-3 and the dimeric molecules of 6 are linked by terminal 4-PM H-bonds to create 2D supramolecular square-grid hydrogen-bonded networks. On the other hand, the 1D polymeric chains of 4 are linked into a 2D supramolecular network, while two coordination chains of 5 come together to generate a ladder type double chain. (C) 2021 Elsevier Ltd. All rights reserved.