反应详情

A 250 mL round-bottom flask equipped with a reflux condenser was charged with zinc-copper couple (6.5 g, 0.05 mol) and ethyl ether (100 mL). Iodine (0.42 g, 0.00165 mol) was added and stirred until the brown color disappeared. Diiodomethane (26.56 g, 0.09915 mol) was added and heated at reflux for 2 h. 8-Methylene-1,4-dioxaspiro[4.5]decane (10 g, 0.06 mol), dissolved in ethyl ether (50 ml) was added and the mixture was heated at roflux overnight. An additional portion of diiodomethane (26.56 g, 0.09915 mol), zinc-copper couple (6.5 g, 0.05 mol) and iodine (0.42 g, 0.00165 mol) was added and the reaction was continued at reflux for overnight. The reaction mixture was cooled to room temperature, filtered, and the precipitate was rinsed with ethyl ether (100 mL). The combined ether solutions were placed in a 500 mL round-bottom flask and IN hydrochloric acid (200 mL) was added and stirred at room temperature for 1 hour. The layers were separated and the aqueous layer was extracted with ethyl ether (2×200 mL). The combined organic layers were dried and concentrated under educed pressure. The residue was purified by flash chromatography to afford the desired product. (4.6 g 50%).

1. customA 250 mL round-bottom flask equipped with a reflux condenser
2. temperatureheated
3. temperatureat reflux for 2 h
4. additionwas added
5. temperaturethe mixture was heated at roflux overnight
6. temperatureat reflux for overnight
7. filtrationfiltered
8. washthe precipitate was rinsed with ethyl ether (100 mL)
9. customThe combined ether solutions were placed in a 500 mL round-bottom flask and IN hydrochloric acid (200 mL)
10. additionwas added
11. stirringstirred at room temperature for 1 hour
12. customThe layers were separated
13. extractionthe aqueous layer was extracted with ethyl ether (2×200 mL)
14. customThe combined organic layers were dried
15. concentrationconcentrated under educed pressure
16. customThe residue was purified by flash chromatography