Fluorescent Sensing Properties of Three Coordination Polymers Constructed by 3,5‐Di(2′,5‐dicarboxylphenyl)pyridine Ligand

Three Cd II coordination polymers (CPs), named as {[Cd 2 (DDPP)(DMF)(H 2 O)] · DMF} n ( 1 ), {[Cd 2 (DDPP)(H 2 O) 2 ] · DMA · H 2 O} n ( 2 ), [Cd(H 2 DDPP)] n ( 3 ), based on 3,5‐di(2′,5‐dicarboxylphenyl)pyridine) (H 4 DDPP), were synthesized under solvothermal methods. Structural analysis indicates that the H 4 DDPP ligand of 1 – 3 adopt (κ 1 ‐κ 1 )‐(κ 1 ‐κ 1 )‐(κ 1 ‐κ 2 )‐(κ 1 ‐κ 1 )‐μ 8 , (κ 1 ‐κ 1 )‐(κ 1 ‐κ 2 )‐(κ 1 ‐κ 2 )‐(κ 1 ‐κ 1 )‐μ 10 , and (κ 0 ‐κ 0 )‐(κ 1 ‐κ 2 )‐(κ 1 ‐κ 2 )‐(κ 0 ‐κ 0 )‐μ 6 coordination modes, respectively. CP 1 is a 2‐nodal (4,8)‐c alb ‐ 4 , 8 ‐ Pbcn network. CP 2 is a 3D 4,8‐c flu/fluorite network. CP 3 displays a 2D layer, which is further connected with hycrogen‐bonding interactions between layers to form supramolecular framework. Moreover, the fluorescent features of 1 – 3 were studied in aqueous systems and the values of detection limit (DL) are also calculated by 3σ/ k sv . The results reveal that 1 – 3 have good ability on probing Cr VI /Fe III ions.