Structural diversity and luminescence sensing of cadmium coordination polymers derived from 5-(bis(4-carboxybenzyl)amino) isophthalic acid

Reactions of cadmium ions with the flexible tetracarboxylic ligand, 5-(bis(4-carboxybenzyl)amino) isophthalic acid (H4L) gave rise to four complexes, namely {[(Me2NH2)(2)Cd-3(L)(2)]center dot 10H(2)O)}(n) (1), {[Cd-2(L)(pdp)(H2O)(2)]center dot 2DMF center dot 4H(2)O}(n) (pdp = 4-[(E)-4-Pyridinylazo]pyridine) (2), {[Cd-2(L)( 1 )Re)(H2O)(2)]center dot 2DMF center dot 4H(2)O}(n) (bpe = 1,2-bi (4-pyridyl)ethene) (3) and {[Cd-4(L)(2)(bpmp)(3)]center dot 2H(2)O}(n) (bpmp = N,N'-bis-(4-pyridyl-methyl) piperazine) (4). Compound 1 features a three-dimensional anionic architecture constructed by triangular Cd-3 cluster and ligands, with rectangle channels encapsulating [Me2NH2](+) cations. Compounds 2 and 3 present similar structures, exhibiting the 2D polythreading layer. Compound 4 possesses a 3D structure with 4,6-connected new topology. The powder X-ray diffraction, the thermal stabilities, and solid-state luminescence properties were studied for 1-4. Furthermore, the luminescent sensing of compounds 1 and 4 toward nitrobenzene has also been investigated.