Boron tribromide → Benzofuran-5-ol

To a stirred solution of 5-methoxybenzofuran (1) (0.50 g, 3.38 mmol) in dichloromethane (15 mL), boron tribromide (16.87 mL, 16.87 mmol, 1M solution in dichloromethane) was added slowly at 0° C. The reaction mixture was warmed to room temperature and stirred for 4 hours. The reaction mixture was then cooled to 0° C., quenched with aqueous saturated NaHCO3 solution and extracted with dichloromethane (3×50 mL). The combined organic extracts were washed with brine (25 mL), dried over Na2SO4, and concentrated under reduced pressure to give compound (2) as an off white solid (300 mg) which was used in the next step without further purification.

1. temperatureThe reaction mixture was then cooled to 0° C.
2. customquenched with aqueous saturated NaHCO3 solution
3. extractionextracted with dichloromethane (3×50 mL)
4. washThe combined organic extracts were washed with brine (25 mL)
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under reduced pressure

ORD record

ord-45cd44a9f1524693a6855f4df5cfa5d2

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309267B2