Chlorination method for industrial production of sucralose-6-acetate

A chlorination method for industrial production of sucralose-6-acetate. The method comprises steps of: (a) adding thionyl chloride into an organic solvent below 30 DEG C to form a mixed solution, with a molar ratio of the organic solvent to thionyl chloride of 3.5-4.6:1; (b) adding sucrose-6-acetate with water content of 0.2%-0.8% into the mixed solution, and stirring, wherein a molar ratio of added sucrose-6-acetate to thionyl chloride is 1:7-9; and (c) slowly heating to 110-113 DEG C in 6-7 h; and after the reaction, subjecting the reaction product to neutralization, solvent removal, decolorization by adding water and crystallization to obtain the sucralose-6-acetate crude product. According to the invention, sucrose-6-acetate containing water is adopted for chlorination, and thionyl chloride is added once without cooling, so as to speed up the process, and reduce energy consumption. The employed solvent is more conducive to release of gas products such as sulfur dioxide generated in the chlorination process and promotion of yield increase, and reduces the generation of the other salts and separation burden.