Solvothermal self-assembly of Cd2+ coordination polymers with supramolecular networks involving N-donor ligands and aromatic dicarboxylates: synthesis, crystal structure and photoluminescence studies

Two cadmium(II) coordination polymers (CPs) of compositions {[Cd(H2O)4(4-BPDB)][BPDC]}n (CP1) and {[Cd(H2O)(BrIP)(BTTMB)]·4MeOH}n (CP2) have been synthesized by solvothermal methods and characterized by several analytical methods including SXRD (Single Crystal X-ray Diffraction). The structure of CP1 can be described as a 1D cationic chain, {[Cd(H2O)4(4-BPDB)]2+}n and discrete BPDC counter anions. The structure of CP2 revealed an undulated 2D sql net comprising Cd2+ nodes bridged by the ditopic N-donor, BTTMB and dicarboxylate BrIP involved in μ2–η1η1η1η1 coordination. Supramolecular interactions in both CPs generate 3D hydrogen bonded architectures. The solid state fluorescence properties of these d10 metal ion containing CPs have been investigated. Fluorescence emission of CP1 suspended in acetonitrile is observed to be selectively quenched by acetone (LOD = 0.15 mM) over other common laboratory solvents.