反应详情

A mixture of 2-benzoyloxymethyl-3-oxo-1,3-dithiolane (example 13) (5.1 g), sodium acetate (65 g) and acetic anhydride (100 ml) was heated at refluxing for 3 hours. Excess reagent was removed under reduced pressure. The residue was dissolved in methylene chloride (200 ml), washed first with saturated aqueous NaCO3 solution (3×100 ml), then with water (100 ml), and finally with brine solution (100 ml), dried over MgSO4, and filtered. The filtrate was evaporated in vacuo and the residue purified by chromatography on silica gel using hexane:ethyl acetate (9:1) as eluant. The desired product was a byproduct and obtained in 9% yield (535 mg) as a mixture cis- and trans-isomer which was characterized by spectroscopic methods.

1. temperaturewas heated
2. temperatureat refluxing for 3 hours
3. customExcess reagent was removed under reduced pressure
4. dissolutionThe residue was dissolved in methylene chloride (200 ml)
5. washwashed first with saturated aqueous NaCO3 solution (3×100 ml)
6. dry with materialwith water (100 ml), and finally with brine solution (100 ml), dried over MgSO4
7. filtrationfiltered
8. customThe filtrate was evaporated in vacuo
9. customthe residue purified by chromatography on silica gel
10. customobtained in 9% yield (535 mg) as a mixture cis- and trans-isomer which