反应详情

To a solution of 0.35 g (1.5 mmol) of 3-methyl-4-vinyl-1-benzofuran-2-carboxylate (Example 87, Step 1) in 3 mL of THF, cooled in an ice bath, was added 1 mL (1 mmol) of borane-THF complex (1.0M solution in THF). The reaction was stirred at room temperature for 2 hours. The reaction was cooled in an ice bath and 1.5 mL of water was added. Next 0.61 g of sodium percarbonate was added in one portion. The reaction was heated at ˜50° C. for 1 hour, then cooled to room temperature. Water was added and the resulting mixture was extracted with ethyl acetate. The organic layer washed with water and brine, dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was chromatographed on silica gel eluting with hexane/ethyl acetate (2:1) to provide 0.20 g of ethyl 4-(2-hydroxyethyl)-3-methyl-1-benzofuran-2-carboxylate. Yield 54%. m.p. 88-90° C.; MS 249.1 (M+H)+.

1. temperatureThe reaction was cooled in an ice bath
2. temperatureThe reaction was heated at ˜50° C. for 1 hour
3. temperaturecooled to room temperature
4. extractionthe resulting mixture was extracted with ethyl acetate
5. washThe organic layer washed with water and brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe residue was chromatographed on silica gel eluting with hexane/ethyl acetate (2:1)