Two new CdII and ZnII coordination polymers incorporating 1‐aminobenzene‐3,4,5‐tricarboxylic acid: synthesis, crystal structure and characterization

Aminobenzoic acid derivatives are widely used in the preparation of new coordination polymers since they contain O‐atom donors, as well as N‐atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. Two new coordination polymers incorporating 1‐aminobenzene‐3,4,5‐tricarboxylic acid (H3abtc), namely, poly[(μ3‐1‐amino‐5‐carboxybenzene‐3,4‐dicarboxylato)diaquacadmium(II)], [Cd(C9H5NO6)(H2O)2]n, (I), and poly[[bis(μ5‐1‐aminobenzene‐3,4,5‐tricarboxylato)triaquatrizinc(II)] dihydrate], {[Zn3(C9H4NO6)2(H2O)3]·2H2O}n, (II), have been prepared and structurally characterized by single‐crystal X‐ray diffraction. In polymer (I), each tridentate 1‐amino‐5‐carboxybenzene‐3,4‐dicarboxylate (Habtc2−) ligand coordinates to three CdII ions to form a two‐dimensional network structure, in which all of the CdII ions and Habtc2− ligands are equivalent, respectively. Polymer (II) also exhibits a two‐dimensional network structure, in which three crystallographically independent ZnII ions are bridged by two crystallographically independent pentadentate 1‐aminobenzene‐3,4,5‐tricarboxylate (abtc3−) ligands. This indicates that changing the metal ion can influence the coordination mode of the H3abtc‐derived ligand and further influence the detailed architecture of the polymer. Moreover, the IR spectra, thermogravimetric analyses and fluorescence properties were investigated. Two new coordination polymers based on 1‐aminobenzene‐3,4,5‐tricarboxylic acid (H3abtc) have been prepared and structurally characterized. CdII ions are linked by tridentate Habtc2− ligands in one polymer, while ZnII ions are bridged by pentadentate abtc3− ligands in the second polymer.