Crystal Structures, Magnetism, and Dye Degradation Catalytic Properties of Copper 2‐Methoxycarboxybenzoate Coordination Complexes

Abstract

Copper coordination complexes containing the 2‐methoxycarboxybenzoate (2‐mcob) ligand show different topologies depending on the nature of the dipyridyl coligand. [Cu2(2‐mcob)2(ebin)]n (1) [ebin = ethanebis(isonicotinamide)] shows a ladder structure based on anti‐syn bridged [Cu(OCO)]n chain motifs. [Cu2(2‐mcob)2(bbin)(H2O)2] (2) [bbin = butanebis(isonicotinamide)] displays a dimeric molecular structure. [Cu2(2‐mcob)2(hbin)]n (3) [hbin = hexanebis(isonicotinamide)] manifests a ladder structure very similar to that of 1. {[Cu(2‐mcob)(dpa)]·H2O}n (4) [dpa = bis(4‐pyridyl)amine] shows a chain coordination polymer structure. All four materials showed significant promise as heterogeneous degradation catalysts for Congo Red dye in aqueous suspension under ultraviolet irradiation. Variable temperature magnetic susceptibility experiments for 1 indicated the presence of weak antiferromagnetic exchange (g = 2.059(2), J = –0.84(2) cm–1). Thermal degradation behavior is also discussed.