Preparation and crystal structure of two novel cadmium (II)–trimesates, Cd(HTMA)(NC5H5)2 · 0.5CH3OH · 0.5DMF and Cd(HTMA) · 2H2O

Two novel complexes, Cd(HTMA)(NC5H5)2 · 0.5CH3OH · 0.5DMF (1) and Cd(HTMA) · 2H2O (2), of cadmium (II)–trimesates are obtained from slow vapor diffusion and urea hydrolysis, respectively. The Cd(II) centers in the two complexes are bridged by three separate HTMA3− ligands using a same coordination fashion, which contains one monodentate and two chelating bidentate carboxyl groups to form the herringbone-like motif. The herringbone-like motif is further interlinked to construct the two-dimensional Cd(II)–HTMA layer, which is stacked by mutual π-stacking of pyridines for 1 and by hydrogen bond of waters for 2. Thermal stabilities of the two complexes were investigated and the results indicated that Cd(II)–TMA layers in the two complexes are stable still upon 190 °C.