反应详情

A mixture of 4-hydroxyindole (0.100 g, 0.75 mmol, 1.0 eq), powdered potassium hydroxide (0.046 g, 0.83 mmol, 1.1 eq), and DMSO (2 mL) was stirred at room temperature for 1 hour and then ethyl 2-bromo-2-methylpropionate (0.161 g, 0.12 mL, 0.83 mmol, 1.1 eq) was added to the above mixture dropwise. The reaction mixture was stirred at room temperature for another 2 hours before 15 mL of water was added. The mixture was extracted with ethyl acetate (2×30 mL). The organic layer was collected, combined, washed with water (6×25 mL) and brine (2×20 mL), and dried over anhydrous Na2SO4. The solvent was removed in vacuo. The residue thus obtained was purified by flash chromatograph over silica gel using hexane/ethyl acetate (95/5) as an eluant to afford 2-(1H-indol-4-yloxy)-2-methylpropionic acid ethyl ester (0.144 g, yield: 80%).

1. additionwas added
2. extractionThe mixture was extracted with ethyl acetate (2×30 mL)
3. customThe organic layer was collected
4. washwashed with water (6×25 mL) and brine (2×20 mL)
5. dry with materialdried over anhydrous Na2SO4
6. customThe solvent was removed in vacuo
7. customThe residue thus obtained
8. customwas purified by flash chromatograph over silica gel