Syntheses, structures, luminescent and magnetic properties of two coordination polymers based on a flexible multidentate carboxylate ligand

Abstract

Two coordination polymers, {[Cu3(tci)2(DMAc)3]·6DMAc·2H2O}n (1) and {[Cu3(tci)2(tpt)2(H2O)2]·2DMAc·2H2O}n (2) (H3tci = tris(2-carboxyethyl)isocyanurate, tpt = 2,4,6-tris(4-pyridyl)-1,3,5-triazine, DMAc = N,N-dimethylacetamide), have been constructed under solvothermal conditions. Both polymers were structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric (TG) analyses and powder X-ray diffraction (RXPD). 1 shows a (3,4)-connected 2D layer structure comprising Cu2(CO2)4 paddle-wheel units, which are further bridged by CH⋯O interactions to give a 3D supramolecular network. The introduction of tpt produces different framework for 2 that comprises a dinuclear and a mononuclear Cu(II) building units, which are further bridged together by tci3− and tpt ligands to give a 4-connected 2D topological net. Adjacent 2D layers are packed together via CH⋯O interactions and π⋯π stacking interactions to form a 3D supramolecular structure. In addition, the luminescent properties and the solid-state UV–vis spectra of 1 and 2 were explored. Furthermore, antiferromagnetic exchange interactions were unveiled in the Cu2(COO)4 units of 1.