Abstract
Two new metal-organic frameworks (MOFs) {[Cu3(timb)2(chtc)2]·14H2O}n, (I) and {[Co3(timb)2(chtc)2]·6H2O}n, (II) were hydrothermally synthesized by corresponding metal salt with mixed organic ligands of 1,3,5-tris[(1H-imidazol-1-yl)methyl]benzene (timb) and cyclohexane-1,3,5-tricarboxylic acid (H3chtc). Crystal structural analysis reveals that they exhibit varied structures. In the MOFs (I), CuII adopts an four coordination geometry, timb and cyclohexane-1,3,5-tricarboxylate ligands bridge neighboring CuII centers to result in two different one-dimensional knotted chains along the [0 − 1 2] and [1 0 − 1] directions, respectively. The two kinds of chains intersect each other vis CuII centers, resulting in a two-dimensional layered structure running parallel to the (1 2 1) plane. Adjacent layers are further linked by water moleculars via classical O–H…O hydrogen-bonding interactions, giving rise to a three-dimensional supramolecular network structure in the solid state. While in MOFs (II), the cyclohexane-1,3,5-tricarboxylate anions link the CoII cations to generate a two-dimensional sheeted metal-organic structure running parallel to the bc plane. Adjacent sheets are further bridged by timb ligands, forming a porous three-dimensional metal-organic framework with a rare (3, 4)-connected (6.82)2(62.84)3(62.8)2 topology. The solvent water molecules guest in the micropores of porous framework via water-carboxylate O–H…O hydrogen bonds. In addition, their thermal stabilities have also been investigated.
Supplementary material
CCDC 2099294 and 2099295 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.