20130102773 | METHOD OF PREPARING SUCRALOSE-6-ESTER BY CATALYSIS AND CHLORINATION OF PHASE TRANSFER CATALYST - A method of preparing sucralose-6-ester by catalysis and chlorination of phase transfer catalyst comprises the following steps: add phase transfer catalyst into a prepared Vilsmeier reagent and then drip in DMF solution of sucrose-6-ester at 5-10° C. to obtain a feed solution and after that maintain its temperature of the feed solution for 1-1.5 hours; next, increase temperature of the feed solution to 45-55° C. and maintain the temperature for 1-1.5 hours; next, increase the temperature to 75-85° C. and maintain the temperature for 1-1.5 hours; next, increase the temperature to 108-109° C., maintain the temperature for 2.5-3 hours and then remove a chlorine-containing solvent from the feed solution by concentration in reduced pressure for evaporation. After that, cool down the feed solution to room temperature and then pump in ammonia into the feed solution for neutralization. | 04-25-2013 |