Construction of two Zn(ii)/Cd(ii) multifunctional coordination polymers with mixed ligands for catalytic and sensing propertiesElectronic supplementary information (ESI) available: Selected bond lengths, hydrogen bonds, PXRD patterns, TG analysis, leaching experiment, the sensing test of compound 1 and H1-NMR spectroscopy. CCDC: 1814678 for complex 1 and 1814680 for complex 2. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8nj02055h

With the purpose of exploring the catalytic and sensing properties of crystalline materials, two coordination polymers were rationally constructed by the reactions of Zn( ii )/Cd( ii ) ions with methyl-3-hydroxy-5-carboxy-2-thiophenecarboxylate (H 2 L) and bis(4-pyridylformyl)piperazine (bpfp) mixed ligands. Compound 1 features a 2D layered structure and compound 2 shows a 2D + 2D → 3D inclined polycatenation structure. Due to the presence of uncoordinated carbonyl moieties, the two CPs exhibit effective heterogeneous Lewis base catalytic activities to Knoevenagel condensation, and compound 1 shows higher catalytic activity than compound 2 under the same reaction conditions. Interestingly, the two CPs display strong ligand-based photoluminescence both in the solid state and in aqueous solution. More importantly, the sensing test results indicate that compound 2 as a sensor material can selectively recognize l -cysteine through the luminescence quenching effect. Two Zn( ii )/Cd( ii ) coordination polymers with different networks were constructed with mixed ligands. The former compound shows high catalytic activity for Knoevenagel condensation, and the latter compound can selectively recognize l -cysteine through the luminescence quenching effect.