反应详情

A solution of ε-caprolactone (30 g) in 2-propanol (250 ml) at 0° C. was saturated with hydrogen bromide gas. Sulphuric acid (18M, 5 ml) was then added and the solution was heated under reflux for 16 hours. The reaction mixture was poured into water (200 ml), basified with sodium hydrogen carbonate, and extracted with diethyl ether. The combined extracts were dried (Na2SO4) and the solvent was evaporated off under reduced pressure to give the crude product which was purified by column chromatography (alumina, dichloromethane) to give isopropyl 6-bromohexanoate as a pale-yellow oil.

1. customat 0° C.
2. temperaturethe solution was heated
3. temperatureunder reflux for 16 hours
4. extractionextracted with diethyl ether
5. dry with materialThe combined extracts were dried (Na2SO4)
6. customthe solvent was evaporated off under reduced pressure
7. customto give the crude product which
8. customwas purified by column chromatography (alumina, dichloromethane)