Syntheses and structural characterization of six ionic salts based on bis(benzimidazole)/bis(imidazole) and perchlorometallates of Zn and Cu

Abstract

Six salts, ([(H₂L1)(ZnCl₄)] (1) (L1 = 1,1′-bis(benzimidazolyl)methane), [(H₂L1)(CuCl₄)]·H₂O (2), [(H₂L2)(ZnCl₄)] (3) (L2 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole), [( H₂L2)(CuCl₄)] (4), [(H₂L3)(CuCl₄)]·H₂O (5) (L3 = 1- (4-(1H-benzimidazol-1-yl)butyl)-1H-benzimidazole), and [(H₂L4)(ZnCl₄)]·H₂O (6) (L4 = 3,6-bis(imidazol-1-yl)pyridazine)), derived from bis(benzimidazole)/bis(imidazole) and metal(II) chloride dihydrate (zinc(II) chloride and copper(II) chloride dihydrate) were prepared and characterized by IR, X-ray structure analysis, elemental analysis, and TG analysis. The aromatic rings of the cations in all of the compounds are planar. X-ray diffraction analysis revealed that all the complexes have 3-D layer network structures built from hydrogen bonds between the cations and chlorometallate anions. Water molecules also play an important role in structure extension in 2, 5, and 6. The arrangements of the anions and cations in their solid state are dominated not only by size and symmetry of the cations, but also by the non-covalent interactions existing in the crystal structures.

Graphical Abstract

Due to the weak interactions, the compound displays 3-D layer structure.

Keywords:

• Zinc
• Copper
• Crystal structure
• Bis(benzimidazole)
• Ionic salts

Additional information

Funding

Funding. This research was supported by Zhejiang Provincial Natural Science Foundation of China under [grant number LQ12B02001]; Zhejiang Province Key Laboratory of Noble Metal Catalytic Materials and Technology under [grant number 2013F10008] and Zhejiang Provincial Natural Science Foundation of China under [grant number LY14B010006] for the subsequent granted time of these foundations.