反应详情

To a stirred and ice-cooled mixture of Compound 3 (10.0 g, 27.1 mmol), 3.0 M NaOH aq. (36.1 ml, 108.4 mmol) and tert-BuOH (15.0 ml) was added (tert-BuOCO)2O (Boc2O, 7.39 g, 33.8 mmol). After stirring at room temperature overnight, the mixture was extracted with AcOEt (×3). The combined AcOEt extracts were washed with sat. NaHCO3 and brine, dried over Na2SO4, and concentrated to give Compound 4 (11.3 g, quant.) as a pale yellow syrup.

1. temperatureice-cooled
2. stirringAfter stirring at room temperature overnight
3. extractionthe mixture was extracted with AcOEt (×3)
4. washThe combined AcOEt extracts were washed with sat. NaHCO3 and brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated