反应详情

A 1M solution of boron tribromide in dichloromethane (55 cm3) was added dropwise to a solution of 2-cyano-5-(4-methoxyphenyl)thiophene (2.3 g) and dichloromethane (80 cm3) at 0° C. under an atmosphere of nitrogen. The reaction solution was stirred overnight and water (100 cm3) added. The organic layer was separated off and the aqueous layer extracted with dichloromethane (2×100 cm3). The combined organic layers were washed with brine (2×100 cm3) and then dried (MgSO4), filtered and evaporated down. The residue was purified by column chromatography on silica gel using a 9:1 hexane/ethyl acetate mixture as eluent and recrystallisation from ethanol to yield 1.4 g of g 2-cyano-5-(4-hydroxyphenyl)thiophene.

1. customThe organic layer was separated off
2. extractionthe aqueous layer extracted with dichloromethane (2×100 cm3)
3. washThe combined organic layers were washed with brine (2×100 cm3)
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. customevaporated down
7. customThe residue was purified by column chromatography on silica gel using a 9:1 hexane/ethyl acetate mixture as eluent
8. customrecrystallisation from ethanol