Herbicide isoxaflutole synthesis method

The invention discloses a herbicide isoxaflutole synthesis method. According to the synthesis method, 5-cyclopropyl-4-[2-methylthio-4-(trifluoromethyl) benzoyl] isoxazole (I) is used as raw materials and mixed with haloalkane solvents including oxidation catalysts composed of sodium tungstate, ammonium tungstate, sodium molybdate or ammonium molybdate, phase transfer catalysts composed of trioctyl methyl ammonium chloride, methyltributylammonium bromide or trioctyl methyl ammonium hydrogen sulfate, and inorganic acid, after mixing, hydrogen peroxide with the concentration being 30% is added dropwise, concentration is performed after the mixture stands and is layered, and finally, isoxaflutole (II) can be obtained. According to the method, the reaction condition is mild, operation is easy, three-water is little, a reaction can be controlled easily, the yield and the content of products are high, and the method is suitable for environment-friendly industrial production.