Crystal structure and catalytic properties of a vanadium complex cis-[VO₂(Him-py)(im-py)]₂·3H₂O

Abstract

The coordination behavior of Him-py (2-(1H-imidazol-2-yl)pyridine) toward vanadium has been explored. The six-coordinate complex, cis-[VO₂(Him-py)(im-py)]₂·3H₂O (1), was synthesized by the coordination reaction of NH₄VO₃ and Him-py in the aqueous methanol solution, which was characterized by single-crystal X-ray technology. It belongs to the monoclinic space group P2₁/n with a = 8.0756(6), b = 19.3531(15), c = 11.4433(8), β = 106.905(2), V = 1711.2(2), and Z = 2. The crystal structure shows that the six-coordinate vanadium is bonded to two cis-oxido ligands and two bidentate ligands, Him-py and im-py. Interestingly, when crystals of 1 were immersed in H₂O₂, a peroxovanadium compound, (H₂im-py)[OV(O₂)₂(Him-py)] (2), was obtained, which crystallizes in the orthorhombic space group Fdd2 with a = 22.600(2), b = 22.7259(13), c = 18.0146(11), V = 9252.4(12), and Z = 16, and consists of a seven-coordinate peroxovanadate(V) ion, one Him-py and one H₂im-py ligand. Moreover, we also studied the catalytic activity of 1 in the oxidative bromination of phenol/aniline-like compounds towards mimicking bromoperoxidase reactivity.

Keywords:

• Vanadium complex
• 2-(1H-Imidazol-2-yl)pyridine
• crystal structure
• catalysis

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (21601058), Scientific Research Fund of Hunan Provincial Education Department (18A192), and Natural Science Foundation of Hunan Province (2018JJ3146).