反应详情

2-(4-Chlorophenyl)-2-hydroxyacetic acid (40 g; 0.2 mol) is dissolved in 100 ml of methanol and stirred at +20° C. At this temperature 5 ml of concentrated sulfuric acid are added dropwise. After the addition is complete the reaction mixture is heated up to +45° C. and stirred for further 30 minutes. Then the reaction mixture is poured into a cooled (0° C.) solution of sodium carbonate (42 g; 0.4 mol) in 300 ml of water. The product is extracted with toluene (3×50 ml) washed with brine (3×50 ml) dried (Na2SO4) and evaporated. After crystallization from diethylether/hexane (10 g/80 g) 2-(4-chlorophenyl)-2-hydroxyacetic acid methylester (34 g; 84% yield) is obtained as a colorless solid. M.p. 54-55° C.

1. additionAfter the addition
2. temperatureis heated up to +45° C.
3. stirringstirred for further 30 minutes
4. additionThen the reaction mixture is poured into
5. extractionThe product is extracted with toluene (3×50 ml)
6. washwashed with brine (3×50 ml)
7. dry with materialdried (Na2SO4)
8. customevaporated