反应详情

温度

0 °C

1.3 g of anhydrous zinc chloride and 13.2 g of granular manganese are heated to boiling in 100 ml of tetrahydrofuran and boiled with 0.2 ml of methallyl bromide for 30 minutes. Then, the solution of 25 g of methallylbromide and 17 g of trifluoropyruvic acid ethyl ester in 80 ml of tetrahydrofuran is added in drops at boiling heat over two hours and boiled for another hour. Then, it is added to saturated ammonium chloride solution and 300 ml of ethyl acetate while being cooled with ice, stirred for 30 minutes at 0° C., and the separated ethyl acetate phase is washed with saturated ammonium chloride solution and three times with water. The solvent is dried (Na2SO4) and concentrated by evaporation, and the residue is distilled in a vacuum. 17.6 g of 2-hydroxy-4-methylene-2-trifluoromethyl-valeric acid ethyl ester, boiling point 48° C., 1 hPa, is obtained.

1. temperatureat boiling heat over two hours
2. waitboiled for another hour
3. temperaturewhile being cooled with ice
4. washthe separated ethyl acetate phase is washed with saturated ammonium chloride solution and three times with water
5. dry with materialThe solvent is dried (Na2SO4)
6. concentrationconcentrated by evaporation
7. distillationthe residue is distilled in a vacuum