Copper 3,4-pyridinedicarboxylate mixed ligand coordination polymers with diverse topologies and aqueous Congo Red degradation catalytic properties

Abstract

Hydrothermal reaction of copper nitrate, 3,4-pyridinedicarboxylic acid (34pdcH2), and a variety of ditopic dipyridyl ligands afforded six new coordination polymer solids with diverse 2D and 3D topologies as characterized via single-crystal X-ray diffraction. {[Cu(34pdc)(dpa)]·H2O}n (1, dpa = 4,4′-dipyridylamine) reveals a 3,5-connected layered net with a (426)(42678) topology. [Cu(34pdc)(3pina)]n (2, 3pina = 3-pyridylisonicotinamide) manifests a 2-fold interpenetrated 3,5-connected 3D net with (426)(426583) topology. [Cu2(34pdc)2(bbn)(H2O)2]·7H2O}n (3, bbn = bis(butane-1,4-diyl)nicotinamide) shows a 3D trinodal network with {(63)2(6.102)(64102)} topology, with looped pairs of bbn ligands acting as single connectors. [Cu4(34pdc)4(bbin)(H2O)4]·8H2O}n (4, bbin = bis(butane-1,4-diyl)isonicotinamide) displays a quite complicated 3D multinodal network with {(63)2(628)(6282102)(668310)} topology. [Cu2(34pdc)2(pebn)(H2O)]·8H2O}n (5, pebn = bis(pentane-1,5-diyl)nicotinamide) shows a 3,4,4-connected 2D network with {(63)2(6472)(6.74.11)} topology, along with entrapped chair-centered 14-water molecule clusters. [Cu4(34pdc)4(hbn)(H2O)4]·3H2O}n (6, hbn = bis(hexane-1,6-diyl)nicotinamide) showed the same {(63)2(6.102)(64102)} topology as 3, but with single dipyridylamide ligands instead of looped pairs. Thermal decomposition of these six new materials are also probed, along with their catalytic behavior for the aqueous degradation of Congo Red dye in the presence of ultraviolet radiation and hydrogen peroxide.