3-Bromo-2,4-pentanedione was synthesized from 2,4-pentandione and pyridinium bromide perbromide salt. The effects of the reaction material ratio,medium,temperature and time on the yield of the product were investigated. The optimum reaction condi-tions were obtained:ratio of 2,4-pentanedione to pyridinium bromide perbromide1. 2 : 1,the dichloromethane as solvent,1. 5 h of reaction time under the reaction temperature 45℃. The yield under this optimum reaction conditions was up to 92. 5%. The struc-ture of the target product was confirmed by elementary analysis,FT-IR,1 H NMR and 13 C NMR spectroscopy. This method had ad-vantages of simple work-up procedure,eco-friendly and high yield.%以2,4-戊二酮和三溴吡啶盐为原料合成了3-溴-2,4-戊二酮.探讨了合成过程中原料摩尔比、反应介质、反应温度、反应时间等因素对产物收率的影响,获得较佳合成条件:n(2,4-戊二酮):n(三溴吡啶盐)=1.2:1,反应介质为二氯甲烷,反应温度45℃,反应时间1.5 h,产品收率达92.5%.目标产物结构经红外光谱(FT-IR)、元素分析、核磁共振氢谱(1 H NMR)和核磁共振碳谱(13 C NMR)测定和结构表征.此方法具有操作简单、环境友好、产率高的特点.
展开▼
