Structural diversity and dye degradation capability of copper 1,2-phenylenediacetate coordination polymers with flexible dipyridylamide ligands

Abstract

Hydrothermal reaction of copper nitrate, 1,2-phenylenediacetic acid (pdaH2), and flexible dipyridylamide ligands afforded four new coordination polymers with diverse structural topologies, as characterized by single crystal X-ray diffraction. {[Cu(pda)(hdn)(H2O)2]·2H2O}n (1, hdn = N,N′-(hexane-1,6-diyl)dinicotinamide) shows 1D ribbon motifs. In contrast, [Cu(pda)(hdin)]n (2, hdin = N,N′-(hexane-1,6-diyl)diisonicotinamide) presents a rare example of a five-fold interpenetrated 4-connected 658 cds 3D topology. [Cu(pda)(bdn)]n (3, bdn = N,N′-(butane-1,4-diyl)dinicotinamide) displays an unprecedented 3,5-connected binodal (63)(6783) 3D topology with embedded {Cu(OCO)}n axial-equatorial bridged chain motifs. {[Cu(pda)(bpfp)(H2O)]·4H2O}n (4, bpfp = N,N′-(bis-4-pyridylformyl)piperazine) shows rectangular (4,4) grid submotifs. All four materials were assayed as heterogeneous catalysts for the degradation of Congo Red (CR) in aqueous suspension under ultraviolet irradiation; only compound 3 catalyzed the degradation. Thermal properties of 1–4 are also discussed herein.