Two novel 3D MOFs based on the biphenyl-2,4,6,3′,5′-pentacarboxylic acid ligand: Synthesis, crystal structure and luminescence properties.

Two novel 3D metal-organic frameworks [Cd 3 (bpbc)(μ 3 -OH)(H 2 O) 3 ]·H 2 O (1) and [Zn 2 Na (bpbc)(DMF) 1.5 (EtOH) 0.5 (H 2 O) 5 ]·0.5H 2 O (2) have been synthesized by using biphenyl-2, 4, 6, 3′, 5′-pentacarboxylic acid (H 5 bpbc) as the ligand under solvothermal/hydrothermal conditions. The complexes were characterized by elemental analysis, single-crystal X-ray diffraction (XRD), powder X-ray diffraction (PXRD), IR spectra and thermogravimetric analysis (TGA). Structural analysis revealed that complex 1 shows a (5, 10)-connected 3D network based on the [Cd 6 (COO) 10 (μ 3 -OH) 2 ] SBUs with unusual topology, while complex 2 exhibits a (3, 3, 6)-connected 3D framework. The structural difference between 1 and 2 indicated that the coordination fashion of bpbc5− and the kind of metal ions could play critical role in the construction of MOFs. In addition, new fluorescence emissions were observed for 1 and 2 , and the solid state luminescent properties were investigated. Two novel 3D fluorescence metal-organic frameworks [Cd 3 (bpbc)(μ 3 -OH)(H 2 O) 3 ]·H 2 O (1) and [Zn 2 Na (bpbc)(DMF) 1.5 (EtOH) 0.5 (H 2 O) 5 ]·0.5H 2 O (2) have been constructed by using the self-assembly of biphenyl-2, 4, 6, 3′, 5′-pentacarboxylic acid (H 5 bpbc) and Zn2+/Cd2+ ions. Unlabelled Image • Two novel 3D coordination polymers were prepared by the self-assembly of H 5 bpbc and Zn2+/Cd2+ ions. • (5, 10)-connected and (3, 3, 6)-connected 3D framework structures were obtained with the same organic ligand. • The fluorescence properties of complexes 1 and 2 were recorded and discussed. [ABSTRACT FROM AUTHOR]