Synthesis and characterization of binuclear manganese(IV,IV) and mononuclear cobalt(II) complexes based on 2-(2-hydroxyphenyl)-1H-benzimidazole

Abstract

The bidentate benzimidazolic hpbm (1), [2-(2-hydroxyphenyl)-1H-benzimidazole], was obtained under mild conditions, and its corresponding metal complexes, di-µ-oxo dimanganese(IV,IV) [Mn₂O₂(hpbm)₄ · 2Py · 5H₂O] (2), and mononuclear complex [Co(hpbm)₂] (3), were prepared and characterized. The crystal structures of 2 and 3 have been established by X-ray diffraction. Complex 2 consists of two six-coordinate manganese(IV) coordinated to two hpbm ligands and bridged by two O²⁻ with a Mn–Mn distance of 2.777 Å. For 3, a Co(II) is coordinated to two deprotonated hpbm in a nearly tetrahedral environment. Hydrogen bonds play pivotal roles in constructing the dimensional structures of both the compounds.

Keywords:

• 2-(2-Hydroxyphenyl)-1H-benzimidazole
• Di-µ-oxo dimanganese(IV,IV) complex
• Cobalt(II) complex
• Crystal structure

Acknowledgments

This work was supported by the National Natural Science Fund of China (20971103), International Cooperation Foundation of Shaanxi Province and Educational Committee Foundation of Shaanxi Province.