反应详情

A solution of acetate 2 (2.14 g, 10 mmol) in diethyl ether (20 ml) was added to 1.6 M MeLi solution in diethyl ether (26 ml, 40 mmol), while cooling in an ice bath. The reaction mixture was stirred at room temperature for 1 h. It was then cooled in an ice bath and saturated aqueous NH4Cl (20 ml) was added dropwise. The aqueous phase was extracted with diethyl ether (230 ml). The combined organic phases were washed with brine (30 ml), dried over MgSO4, filtered and evaporated. The residue was purified by Kugelrohr short path distillation (100° C./4 mm Hg) to give 29 (1.86 g, 86%) as a colorless oil. 1H-NMR: (CDCl3, TMS): 0.91 and 0.96 (total 12H, both s, c-Hex-3,5-CH3); 1.25 (2H, s, c-Hex-4-CH2); 1.38 (6H, s, —C(CH3)2O); 1.79 and 2.23 (both 2H, both s, c-Hex-2,6-CH2) and 5.39 ppm (1H, s, ═CH—).

1. temperaturewhile cooling in an ice bath
2. temperatureIt was then cooled in an ice bath
3. extractionThe aqueous phase was extracted with diethyl ether (230 ml)
4. washThe combined organic phases were washed with brine (30 ml)
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customevaporated
8. distillationThe residue was purified by Kugelrohr short path distillation (100° C./4 mm Hg)