反应详情

温度

-78 °C

A three-neck flask equipped with a dry ice condenser was cooled to −78° C. and anhydrous ammonia (100 mL) was condensed into the flask. Lithium (134 mg, 19 mmol, 10 equiv) was added, and the resulting blue solution was stirred for 0.5 h. To this was added a solution of compound 19 (550 g, 1.91 mmol) in dry THF (50 mL). After 3 h of stirring, solid NH4Cl was added until the blue color disappeared, and the reaction mixture was allowed to warm to room temperature overnight and aqueous NH4Cl was added. The product was extracted into EtOAc (100 mL×3), and the combined organic extracts were washed with brine, dried and the solvent evaporated. Column chromatography (silica gel eluted with 10% EtOAc in hexanes) gave compound (480 mg, 87%) as a colorless oil: 1H NMR (CDCl3) δ 3.63 (t, J=7.8 Hz, 1H), 0.98 (s, 3H), 0.72 (s, 3H); 13C NMR (CDCl3) δ 212.0, 81.5, 54.0, 46.6, 45.0, 44.5, 43.0, 38.2, 37.9, 35.8, 34.6, 31.8, 30.3, 29.1, 25.5, 24.7, 11.4, 11.1; IR νmax 3416, 1709 cm−1.

1. customA three-neck flask equipped with a dry ice condenser
2. customcondensed into the flask
3. stirringAfter 3 h of stirring
4. temperatureto warm to room temperature overnight
5. extractionThe product was extracted into EtOAc (100 mL×3)
6. washthe combined organic extracts were washed with brine
7. customdried
8. customthe solvent evaporated
9. washColumn chromatography (silica gel eluted with 10% EtOAc in hexanes)