反应详情

To a solution of 500 mg (2.6 mmol) of 2-methanesulfonyl-2-methyl-propionic acid ethyl ester in THF/water (4/1, 5 mL) were added 270 mg (6.6 mmol) of lithium hydroxide monohydrate. The reaction was stirred at room temperature for 18 h. The reaction was further diluted with water (20 mL) and then washed with DCM (2×15 mL). The basic aqueous layer was cooled in an ice bath and acidified with 1M aqueous HCl solution to pH 2. The acidic aqueous layer was extracted with isopropanol/chloroform (1/1, 3×20 mL). The combined organic extracts were washed with brine, dried over Na2SO4 and filtered. Concentration of the filtrate under reduced pressure afforded 413 mg of 2-methanesulfonyl-2-methyl-propionic acid. The compound did not ionise under LCMS conditions, thus the structure was confirmed by 1H-NMR spectroscopy:

1. washwashed with DCM (2×15 mL)
2. temperatureThe basic aqueous layer was cooled in an ice bath
3. extractionThe acidic aqueous layer was extracted with isopropanol/chloroform (1/1, 3×20 mL)
4. washThe combined organic extracts were washed with brine
5. dry with materialdried over Na2SO4
6. filtrationfiltered