Syntheses, crystal structures and magnetic properties of five 5,5′-(1,2-phenylenebis(methoxy))diisophthalate coordination polymers

Abstract

Five new coordination polymers based on 5,5′-(1,2-phenylenebis(methoxy))diisophthalic acid (H4L), namely [Co3(HL)2(phen)2]n·2nH2O (1), [Mn2L(phen)2]n·2nH2O (2), [Cu2L(4-abpt)2(H2O)2]n·2nDMF (3), [Co2L(bpp)2(H2O)3]n·3nH2O (4) and {(CH3)2NH2[Co2L(μ3-OH)(H2O)2]·DMF·H2O}n (5) (4-abpt = 4-amino-3,5-bis(4-pyridyl)-1,2,4-triazole, bpp = 1,3-bis(4-pyridyl)propane, phen = 1,10-phenanthroline), have been synthesized and characterized by elemental analyses, IR spectra, PXRD, thermogravimetry and X-ray structural analysis. Complex 1 is a 2D coordination polymer constructing from hexadentate HL3− ligand, which contains trinuclear cobalt cluster [Co3(COO)6] building block. Complex 2 is a 2D coordination polymer assembled by octadentate L4− ligand. Complex 3 is a 3D metal-organic framework assembled by tetradentate L4− ligand and 4-abpt linker. Complex 4 exhibits a 2D layered network containing 1D [Co2L]n nanotube. Complex 5 is a 2D coordination polymer possessing tetranuclear cobalt cluster Co4(μ3-OH)2(COO)4. Tetracarboxylate exhibits five types of coordination modes. Thermal analyses demonstrate that complexes 1 and 2 were thermal stable up to 400–450 °C. Variable-temperature magnetic studies indicate that complex 1 has ferrimagnetic coupling in the [Co3(COO)6] cluster. Complexes 2 and 5 present antiferromagnetic interactions.