反应详情

A solution of 1-cyclopropylpent-4-en-2-ol (C65) (16 g, 0.127 mmol) in tetrahydrofuran (200 mL) was added to a 0° C. suspension of sodium hydride (60% in mineral oil, 15.2 g, 0.38 mol) in tetrahydrofuran (400 mL). After stirring at room temperature for 10 minutes, 2-bromo-1,1-diethoxyethane (97%, 75 g, 0.38 mol) was added drop-wise at room temperature. The reaction mixture was heated to 70° C. for 24 hours. It was then cooled to 0° C., slowly quenched with water (200 mL) and extracted with dichloromethane (3×500 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo; purification via silica gel chromatography (Gradient: 0% to 10% ethyl acetate in petroleum ether) afforded the product as a yellow oil. Yield: 20 g, 83 mmol, 65%. 1H NMR (400 MHz, CDCl3) δ 5.79-5.89 (m, 1H), 5.04 (dt, J=14.0, 1.6 Hz, 2H), 4.60 (t, J=5.2 Hz, 1H), 3.64-3.73 (m, 2H), 3.51-3.62 (m, 4H), 3.45 (quintet, J=6.0 Hz, 1H), 2.31 (t, J=6.4 Hz, 1H), 1.50 (quintet, J=6.8 Hz, 1H), 1.20-1.30 (m, 2H), 1.21 (dt, J=6.8, 1.2 Hz, 6H), 0.72-0.80 (m, 1H), 0.38-0.49 (m, 2H), −0.02-0.10 (m, 2H).

1. temperatureThe reaction mixture was heated to 70° C. for 24 hours
2. temperatureIt was then cooled to 0° C.
3. customslowly quenched with water (200 mL)
4. extractionextracted with dichloromethane (3×500 mL)
5. dry with materialThe combined organic layers were dried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. custompurification via silica gel chromatography (Gradient: 0% to 10% ethyl acetate in petroleum ether)