反应详情

To a solution of 170 g (0.59 mol) of 2-methyl-2-(4,4,4-trifluoro-butane-1-sulfonyl)-propionic acid ethyl ester in THF (3.4 L) are added 225.4 g (1.76 mol) of potassium trimethylsilanolate in portions over 0.5 h. The reaction is stirred at room temperature for 18 h. The reaction mixture is acidified with 2M aqueous HCl solution (2 L) to pH 2 and extracted with DCM (2×2 L). The combined organic extracts are dried (Na2SO4) and filtered. The filtrate is concentrated under reduced pressure to afford 143 g of 2-methyl-2-(3-methyl-butane-1-sulfonyl)-propionic acid as yellow solids. Yield: 93%; ES-MS: m/z 261 [M−H]. 1H-NMR (500 MHz, CHLOROFORM-d) δ ppm 1.71 (6H, s), 2.18-2.28 (2H, m), 2.30-2.42 (2H, m), 3.38 (2H, t, J=7.48 Hz), 6.96 (1H, br. s.)

1. extractionextracted with DCM (2×2 L)
2. dry with materialThe combined organic extracts are dried (Na2SO4)
3. filtrationfiltered
4. concentrationThe filtrate is concentrated under reduced pressure