Crystal structure of dichloro-(1,4-cyclohexanedicarboxylato)bis-[1,2-bis(imidazole-1-ylmethyl)benzene]dicadmium(II) hydrate, Cd2Cl2(C14H14N4)2(C8H10O4) · H2O

Abstract

Source of materialAm ixture of 1,4-cyclohexanedicarboxylic acid (H 2 chdc, 0.5 . mmol), 1,2-bis(imidazole-1-ylmethyl)benzene (1,2-bix, 0.5 .mmol), and CdCl2.·.2H2O( 0.5 mmol) was suspended in a solution of deionized water (12 ml) and sealed in a20mlTeflon-lined autoclave. Upon heating at 140°Cfor two days, the autoclave was slowly cooled to room temperature. The crystals were collected, washed with deionized water and dried. Experimental detailsHydrogen atoms on carbon atoms were generated geometrically and refined as riding atoms with d(C-H) =0.93 Å and U iso(H) = 1.2 U eq(C). The Hatoms of the water molecules were not located. DiscussionThe design and synthesis of metal-organic coordination polymers have attracted intense interests of chemists [1]. The selection of ligand is extremely important because changing their conformations can control the topology of the resulting coordination framework [1]. While the rigid rod-like spacer, 4,4'-bipyridine, is well known in the construction of metal-organic polymers, flexible N-donor ligands such as 1,2-bix have not been so well explored [2]. The asymmetric unit of the title crystal structure comprises aCd 2+ cation, achloride anion, half achdc dianion, half awater molecule, and one 1,2-bix molecule. Each Cd atom is six-coordinated by three carboxylate oxygen atoms from two different chdc anions, one chlorine ,and two nitrogen atoms from two distinct 1,2-bix ligands in adistorted octahedral sphere. Each chdc ligand bridges apair of Cd atoms to form achain structure.

Equilibrium Hydrate Formation Conditions for the Mixtures of Methane + Ionic Liquids + Water

“…The equilibrium hydrate formation points were measured by an isochoric method. − Prior to the experiments, the crystallizer was washed using deionized water and allowed to dry. Ionic liquid aqueous solution (135 mL) at the desired concentration was introduced into the high-pressure hydrate crystallizer.…”