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

Abstract

Abstract 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 [Cu2(2-Mebz)4(4-PM)]n (4) and [Cu2(3-Mebz)4(4-PM)2]n (5), and the dimeric complex [Cu2(2-Fbz)4(4-PM)2] (6) (where 4-PM\xa0=\xa04-pyridylmethanol, 2-Fbz = 2-fluorobenzoate anion, 3-MeObz = 3-methoxy-benzoate anion and x-Mebz\xa0=\xa02,3,4-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.