Synthesis, X-Ray Structural Characterization, and Catalytic Property of Dioxomolybdenum(VI) Complexes With N’-(3-Bromo-2-hydroxybenzylidene)-2-hydroxybenzohydrazide and N’-(5-Chloro-2-hydroxybenzylidene)-4- nitrobenzohydrazide

Abstract

Two new dioxomolybdenum(VI) complexes [MoO₂(Bhbz) (CH₃OH)] (1) and [MoO₂(Cnbz)(CH₃OH)] (2) with the benzohydrazone ligands H₂Bhbz and H₂Cnbz derived from 5-chlorosalicylaldehyde with 4-nitrobenzohydrazide and 3-bromosalicylaldehyde with 2-hydroxybenzohydrazide, respectively, have been synthesized and structurally characterized by physicochemical methods and single crystal X-ray determination. The crystal of (1) crystallizes in triclinic space group P-1, with a = 8.0014(9), b = 9.6294(10), c = 11.4204(12) Å, α = 89.193(2), β = 87.833(2), γ = 89.110(2)°, V = 879.11(16) ų, Z = 2, R ₁ = 0.0464, wR ₂ = 0.1185, S = 1.051. The crystal of (2) crystallizes in monoclinic space group P2₁/c, with a = 7.4108(3), b = 18.7901(7), c = 12.6293(5) Å, β = 104.4850(10)°, V = 1702.72(12) ų, Z = 4, R ₁ = 0.0236, wR ₂ = 0.0576, S = 1.061. X-ray analysis indicates that the structures of both complexes are similar to each other. The molybdenum atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO₂ donor set of the ligand, and one methanol O atom. The complexes have effective catalytic property for the oxidation of several olefins.

Keywords:

• Benzohydrazone ligand
• synthesis
• catalytic oxidation
• crystal structure
• molybdenum complex

Acknowledgments

This work was supported by the Fundamental Research Funds for the Central Universities (Project No. 0969801), and Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservior (Chongqing Three Georges University).