反应详情

A mixture containing 5-(2-bromoethyl)-2,3-dihydrobenzo[2,3-b ]furan (3 g--see Preparation 13), freshly recrystallised N-bromosuccinimide (2.37 g), benzoyl peroxide (0.03 g) and carbon tetrachloride was heated under reflux for 2 hours. On cooling to room temperature, water (100 ml) and sodium metabisulphite (1 g) were added, the layers were separated and the aqueous layer was extracted with dichloromethane (3×50 ml). The combined organic extracts were dried (MgSO4) and concentrated in vacuo to give an oil which was purified by column chromatography on silica eluting with hexane containing toluene (5%). The product-containing fractions were combined and concentrated in vacuo to give the title compound as an oil, yield 1.25 g.

1. temperaturewas heated
2. temperatureunder reflux for 2 hours
3. customthe layers were separated
4. extractionthe aqueous layer was extracted with dichloromethane (3×50 ml)
5. dry with materialThe combined organic extracts were dried (MgSO4)
6. concentrationconcentrated in vacuo
7. customto give an oil which
8. customwas purified by column chromatography on silica eluting with hexane
9. additioncontaining toluene (5%)
10. concentrationconcentrated in vacuo