反应详情

To a solution of 3.78 g (15.09 mol) of 2-methyl-2-(3-methyl-butane-1-sulfonyl)-propionic acid ethyl ester in THF/water (4/1, 50 mL) are added 1.58 g (37.74 mmol) of lithium hydroxide monohydrate. The reaction is stirred at room temperature for 18 h. The reaction mixture is concentrated under reduced pressure and the residue dissolved in DCM (20 mL) and extracted with water (50 mL). The aqueous layer is cooled in an ice bath and then acidified with 6M aqueous HCl solution to pH 1. The resulting precipitate is isolated by filtration, and dried under reduced pressure at 50° C. to afford 3.35 g of 2-methyl-2-(3-methyl-butane-1-sulfonyl)-propionic acid as white crystalline solids. Yield: 100%; ES-MS: m/z 221 [M−H].

1. concentrationThe reaction mixture is concentrated under reduced pressure
2. dissolutionthe residue dissolved in DCM (20 mL)
3. extractionextracted with water (50 mL)
4. temperatureThe aqueous layer is cooled in an ice bath
5. customThe resulting precipitate is isolated by filtration
6. customdried under reduced pressure at 50° C.