反应详情

温度

-78 °C

To a solution of Example 170A (2.91 g, 8.75 mmol) in 20 mL of tetrahydrofuran at −78° C. was added 1.6 M n-butyllithium in hexanes (7.1 mL, 11.4 mmol). The reaction was stirred at −78° C. for 10 min, then 1.5 mL of dimethyldisulfide was added. The reaction was warmed to ambient temperature and stirred for 2 h, then concentrated in vacuo. The residue was taken up in 50 mL of diethyl ether, then extracted with water (2×15 mL), 2 M NaOH(aq.) (1×15 mL), and brine (1×15 mL), dried over MgSO4, filtered, and concentrated in vacuo to an oil. This was taken up in 15 mL of tetrahydrofuran and treated with 2.0 g (ca. 7 mmol) of tetrabutylammonium fluoride hydrate. The reaction was stirred at ambient temperature for 1 h, then concentrated in vacuo. The residue was taken up in 30 mL of diethyl ether, then extracted with water (2×10 mL), 2M NaOH(aq.) (1×10 mL), and brine (1×10 mL), dried over MgSO4, filtered, and concentrated in vacuo to an oil. The product was purified via silica gel chromatography, eluting with a 20-40% ethyl acetate in hexanes gradient to give 1.23 g (76%) of the alcohol. The product was about 90% pure by 1H NMR analysis.

1. temperatureThe reaction was warmed to ambient temperature
2. stirringstirred for 2 h
3. concentrationconcentrated in vacuo
4. extractionextracted with water (2×15 mL), 2 M NaOH(aq.) (1×15 mL), and brine (1×15 mL)
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo to an oil
8. stirringThe reaction was stirred at ambient temperature for 1 h
9. concentrationconcentrated in vacuo
10. extractionextracted with water (2×10 mL), 2M NaOH(aq.) (1×10 mL), and brine (1×10 mL)
11. dry with materialdried over MgSO4
12. filtrationfiltered
13. concentrationconcentrated in vacuo to an oil
14. customThe product was purified via silica gel chromatography
15. washeluting with a 20-40% ethyl acetate in hexanes gradient