2-Bromo-4-butanolide

96-48-0

5061-21-2

General procedure for the synthesis of α-bromo-γ-butyrolactone from γ-butyrolactone (bromination step): in a 1000 mL reaction vessel equipped with a stirring device, refluxing device, thermometer, dropping funnel, and nitrogen introduction tube, 200 g (2.32 mol) of γ-butyrolactone and 2.76 g (0.086 mol based on 3.7 mol% of γ-butyrolactone) of sulfur were added as the catalyst. 431 g (2.70 mol) of bromine was loaded into a dropping funnel. Stirring was initiated, the reaction temperature was controlled not to exceed 40 °C, and the bromine was slowly added dropwise. After the dropwise addition was completed, the reaction temperature was raised to about 90 °C and the reaction was maintained at this temperature for 1 hour. Subsequently, the temperature was raised to about 110°C and the reaction was continued for 3 hours.