反应详情

温度

-40 °C

Add n-BuLi (1.6M in hexanes, 8.76 mL, 14.02 mmol) portionwise (exotherm) to a solution of 5-bromo-3H-benzooxazol-2-one (1.00 g, 4.67 mmol) in dry THF (28 mL) at −78° C. under N2. Stir at −40° C. for 1 h and add trimethylborate (1.94 g, 18.68 mmol) at once. Warm up to room temperature overnight. Add 1N aqueous HCl (50 mL) and stir for 3 h at room temperature. Extract into ethyl acetate, dry (MgSO4) and concentrate organics to a brown solid. Triturate with hexanes/toluene and collect 766 mg (92%) of the title compound as a brown powder. MS (ES) 179 (M+H), 177 (M−H); HPLC shows 80% purity.

1. temperatureWarm up to room temperature overnight
2. stirringstir for 3 h at room temperature
3. extractionExtract into ethyl acetate
4. dry with materialdry (MgSO4)
5. concentrationconcentrate organics to a brown solid
6. customTriturate with hexanes/toluene
7. customcollect 766 mg (92%) of the title compound as a brown powder