2,3,4,5-四氟苯甲酰乙酸乙酯的合成

Synthesis of ethyl (2,3,4,5-tetrafluorobenzoyl) acetate

以 2 ,3,4 ,5 -四氟苯甲酰氯为起始原料 ,与丙二酸单乙酯钾、无水氯化镁、三乙胺反应 ,再经酸水解得标题化合物 ,收率 95 %。较老工艺收率提高 2 5 %。重点考察了无水氯化镁和三乙胺的配比对反应收率的影响。确定最佳配比为 n( 2 ,3,4 ,5 -四氟苯甲酰氯 )∶ n(丙二酸单乙酯钾 )∶ n(无水氯化镁 )∶ n(三乙胺 ) =1∶ 1 .1∶ 1 .5∶ 1 .

The synthesis of ethyl (2,3,4,5 tetrafluorobenzoyl) acetate from tetraflurobenzoyl chloride and potassium monoethyl malonate was studied.The effect of reaction time,reaction temperature and molar ratio of starting materials on the yield of target compound was discussed. Under the condition of molar ratio tetrafluorobenzoyl chloride∶potassium monoethyl malonate∶Et 3N∶MgCl 2=1∶1.1∶1.05∶1.5;temperature 0～5℃ and reaction time 8h,the yield was as high as 95%.