A cadmium phenylenediacetate isonicotinate network coordination polymer with new topology via in situ amide cleavage

Hydrothermal reaction of cadmium nitrate, 1,4-phenylenediacetic acid (H21,4-phda), and 4-pyridylisonicotinate (4-pina) afforded the network coordination polymer [Cd3(1,4-phda)2(isonic)2(H2O)2]n (1, isonic = isonicotinate) via in situ 4-pina amide cleavage. Exotetradentate phda ligands connect cadmium ions into [Cd3(1,4-phda)2(OCO)2(H2O)2]n layer motifs featuring cadmium carboxylate dinuclear clusters. In turn these layers are pillared by isonic ligands into a non-interpenetrated 3-D network with a novel 3,4,6-connected {4.62}2{6482}{426883102} trinodal topology. Performing a similar reaction with zinc nitrate afforded the known 3-D phase [Zn(1,4-phda)]n, which possesses a previously unidentified 4,4,4-connected {4.6382}2{426282}{6284} topology. Thermal decomposition and luminescent properties of 1 are also discussed herein.