Assembly of two 3-D metal-organic frameworks from Cd(II) and 4,5-imidazoledicarboxylic acid or 2-ethyl-4,5-imidazoledicarboxylic acid

Two new metal-organic frameworks [Cd-3(H2O)(2)(C5N2O4H)(2)center dot H2O] 1 and [KCd(C7N2O4H5)] 2 have been hydrothermally synthesized employing 4,5-imidazoledicarboxylic acid (IMDC) and 2-ethyl-4,5-imidazoledicarboxylic acid (2-EtIMDC) as organic ligands. The single-crystal structure analysis reveals that compound 1 exhibits a 3-D framework, which is generated from 2-D layers pillared by 1-D chains along the c-axis. Compound 2 presents a 3-D structure with 1-D channels, which are connected in a cross-like fashion by [CdN2O3] trigonal bipyramid units and 2-EtIMDC ligands.