Coordination polymers with mixed 1, 3-bis(1-imidazolyl)-5-(imidazol-1-ylmethyl)benzene and multicarboxylate ligands: Synthesis, structure and property

Five new coordination polymers [Zn3(biimb)2(BPT)2]·4DMF·2.5H2O (1), [Zn(biimb)(NDC)]·1.5H2O (2), [Zn(biimb)(NDC)]·3DMF (3), [Cd(biimb)(NDC)0.5Cl]·3H2O (4) and [Cd3(biimb)2(BPDC)3(H2O)4]·4H2O (5) [biimb = 1,3-bis(1-imidazolyl)-5-(imidazol-1-ylmethyl)benzene, H3BPT = biphenyl-3,4′,5-tricarboxylic acid, H2NDC = 2,6-naphthalenedicarboxylic acid, H2BPDC = 4,4′-biphenyldicarboxylic acid, DMF = N,N-dimethylformamide] were synthesized by hydro/solvothermal reactions and characterized by elemental, thermogravimetric analyses, IR, powder and single crystal X-ray diffractions. Complex 1 is a (3,3,4,4)-connected 4-nodal 3D framework. The linkage of Zn(II), biimb and NDC2− makes a 2D network structure of 2, in which biimb acts as a bidentate ligand, while in 3, the biimb ligands display as tridentate and connect Zn(II) to compose 2D networks, which are further linked together by NDC2− to generate 3D structure of 3. 4 is a pillared-layer 3D net containing [Cd(biimb)Cl]+ layers and NDC2− pillars. 5 is an interesting 3-fold interpenetrating 3D net. Photoluminescence and gas adsorption properties of the complexes were investigated.