Syntheses and structural characterizations of three transition metal coordination complexes based on flexible 2,4-dichlorophenoxyacetate (2,4-DCP)

Abstract

Three transition metal coordination complexes, {[Co(2,4-DCP)2(μ 2-H2O)(H2O)2] · (H2O)2} n (1), [Zn(2,4-DCP)(IN)] n (2), and [Mn2(2,4-DCP)3(DMPY)2(μ 2-H2O)(H2O)] · (2,4-DCP) · 0.2(H2O) (3) (2,4-DCP = 2,4-dichlorophenoxyacetate, IN = isonicotinate, DMPY = 5,5′-dimethyl-2,2′-bipyridine), have been prepared under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. Complex 1 displays a 1-D chain through cobalt and bridging water molecules with Co ··· Co distance of 4.028(2) Å. Complex 2 shows a 2-D (4,4) net, which is extended into a 3-D supramolecular framework by weak hydrogen-bonding interactions. Complex 3 consists of discrete dinuclear cations, 2,4-DCP counter ions and free water molecules, which are assembled into a packing structure through π ··· π stacking of inversion-related DMPY ligands and hydrogen bonds. Magnetic susceptibility measurements show weak antiferromagnetic interactions in 1. The photoluminescence and lifetime of 2 in the solid state have also been studied.