反应详情

To a solution of sodium ethoxide freshly prepared from sodium metal (0.104 g, 4.50 mmol) in ethanol (25 mL) was added ethyl 2-(2-acetyl-3-hydroxy-4-tert-butylphenoxy)acetate 11b (1.26 g, 4.28 mmol) and the mixture heated to reflux for 10 minutes. The reaction mixture was cooled and acidified by pouring into 2N HCl (75 mL). The resulting solution was extracted with ethyl acetate (2×35 mL) and the combined extracts dried (Na2SO4), and concentrated. Flash chromatography afforded, in order of elution 3-methyl-4-hydroxy-5-tert-butylbenzofuran, compound 12b. mp 79°-81° C.; 1H NMR d 1.49 (9H, s), 2.48 (3H, s), 5.27 (1H, s), 7.00 (1H, d, J=8 Hz), 7.24 (1H, d, J=8 Hz), 7.26 (1H, s) and ethyl 3-methyl-4-hydroxy-5-tert-butylbenzofuran-2-carboxylate, compound 12 a, mp. 109-112 (from hexane); 1H NMR d 1.42 (3H, J=6 Hz), 1.46 (9H, s), 2.83 (3H, s), 4.43 (2H, q, J=6 Hz), 5.45 (1H, br s), 7.04 (1H, d, J=8 Hz), 7.37 (1H, d, J=8 Hz).

1. temperaturethe mixture heated
2. temperatureto reflux for 10 minutes
3. temperatureThe reaction mixture was cooled
4. extractionThe resulting solution was extracted with ethyl acetate (2×35 mL)
5. dry with materialthe combined extracts dried (Na2SO4)
6. concentrationconcentrated