Réaction #72585

Équation de réaction

methyl(R)-2-hydroxy-2(2-chlorophenyl)acetate

triethylamine

hydrochloric acid

4-nitrobenzenesulfonyl chloride

→

methyl(R)-2-(4-nitrophenylsulfonyloxy)-2(2-chlorophenyl)acetate

Rendement 98.0%

Solvants

dichloromethane

dichloromethane

dichloromethane

Conditions de réaction

Traitement

1. 1
   AutreThe colorless solution obtained
2. 2
   workup.ADDITIONwas added
3. 3
   workup.STIRRINGwhile stirring this mixture
4. 4
   AutreAfter decanting
5. 5
   Lavagethe dichloromethane phase is washed with dilute hydrochloric acid
6. 6
   Concentrationwith water, before being concentrated under reduced pressure
7. 7
   AutreAn analytically pure sample is obtained
8. 8
   Autreafter purifying on a silica column

Mode opératoire

0.72 g (6 mmoles; 0.1 equivalent) of 4-dimethylaminopyridine, 12.0 g (60 mmoles; 1 equivalent) of methyl(R)-2-hydroxy-2(2-chlorophenyl)acetate and 7.8 g (78 mmoles; 1.3 equivalent) of triethylamine and 20 ml of dichloromethane were added to a dry reaction flask. The colorless solution obtained was cooled to 0° C. and then, operating at this temperature, 13.14 g (60 mmoles; 1 equivalent) of 4-nitrobenzenesulfonyl chloride as a solution in 30 ml of dichloromethane was added. The reaction mixture was stirred for 3 hours at 0° C. and 240 ml of 1N hydrochloric acid and 240 ml of dichloromethane was added drop wise, while stirring this mixture. After decanting, the dichloromethane phase is washed with dilute hydrochloric acid and then with water, before being concentrated under reduced pressure. An analytically pure sample is obtained after purifying on a silica column. In this manner, methyl(R)-2-(4-nitrophenylsulfonyloxy)-2(2-chlorophenyl)acetate is obtained: Yield: 98%. Optical purity: 99%.

Source