反应详情

15-Bromo-1-(t-butyldimethylsiloxy)pentadecane (1 g, 2.36 mmol) dissolved in absolute ethyl ether (3 mL) and magnesium (0.115 g) were mixed, and the mixture was refluxed for 40 minutes. Subsequently, 3-ethoxy-2,6,6-trimethyl-2-cyclohexen-1-one (287.5 mg, 1.57 mmol) dissolved in tetrahydrofuran (2 mL) was added thereto. After stirring the mixture for four hours, 10% hydrochloric acid (3 mL) was added, and the reaction was allowed to continue for a further 17 hours under stirring. The reaction mixture was neutralized with sodium hydrogencarbonate, followed by extraction with ethyl ether three times. The organic layers were combined, washed with aqueous sodium chloride solution, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by means of silica gel column chromatography (hexane/ethyl acetate=9/1-6/4; concentration gradient=5%), to thereby afford 222.7 mg (0.61 mmol) of 3-(15-hydroxypentadecyl)-2,4,4-trimethyl-2-cyclohexen-1-one.

1. temperaturethe mixture was refluxed for 40 minutes
2. additionwas added
3. waitto continue for a further 17 hours
4. stirringunder stirring
5. extractionfollowed by extraction with ethyl ether three times
6. washwashed with aqueous sodium chloride solution
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe crude product was purified by means of silica gel column chromatography (hexane/ethyl acetate=9/1-6/4; concentration gradient=5%)