Synthesis, structures and fluorescent properties of cadmium/zinc coordination polymers with 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene and 1,3,5-benzenetricarboxylic acid

The compounds [CdII2(titb)(BTC)Cl]n (1), [ZnII2(titb)(BTC)Cl]n (2) and [ZnII2(titb)(BTC)NO3]n (3), were synthesized with mixed ligands of 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (titb) and 1,3,5-benzenetricarboxylic acid (H3BTC) by solvothermal reactions. All of the three compounds feature novel structurally characterized tri-carboxylate bridged bimetallic units. The binuclear units, completed by titb ligands, are linked by BTC3− anions. X-ray single crystal diffraction analysis reveals that 1 and 2 are isomorphs and each metal-organic frameworks (MOFs) has interesting (3, 6)-connected net topology by self-penetration of two sets of (10, 3)-a nets. Fluorescent analyses in the solid state of 1, 2 and 3 shows that they may be potential photoactive materials.