反应详情

Into a solution of the Compound 2b (0.3 mmol) in dry chloroform (5 ml) was bubbled anhydrous hydrogen chloride. The resulting solution was stirred for 2.5 hours at ambient temperature. The reaction mixture was diluted chloroform (10 ml) and water (5 ml) and then neutralized with concentrated aqueous ammonium hydroxide. The organic phase was separated and the aqueous phase extracted with chloroform (2×20 ml). The combined organic phases were washed with brine, dried over anhydrous sodium sulfate and filtered. The solvent was removed in vacuo and the resulting yellow oil purified by flash chromatography on silica gel eluted with hexane:diethyl ether (1:2). The β-isomer had an Rf =0.4 and the α-isomer had an Rf =0.3.

1. customThe organic phase was separated
2. extractionthe aqueous phase extracted with chloroform (2×20 ml)
3. washThe combined organic phases were washed with brine
4. dry with materialdried over anhydrous sodium sulfate
5. filtrationfiltered
6. customThe solvent was removed in vacuo
7. customthe resulting yellow oil purified by flash chromatography on silica gel
8. washeluted with hexane:diethyl ether (1:2)