反应详情

To a mixture of commercially-available 5-bromobenzo[d]oxazol-2(3H)-one (35-1, 500 mg, 2.336 mmol) in DCM (23 mLl) at RT was added chlorosulfonic acid (1565 μl, 23.36 mmol). The mixture became a solution that was stirred at RT. After 18 h, The solution was cooled to 0° C. and carefully quenched with ice chips and then partitioned between water (15 mL) and EtOAc (150 mL). The aqueous layer was extracted with 3×30 mL DCM. The combined organics were dried over Na2SO4, filtered, concentrated to give 35-2 as a white solid, which was carried forward without further purification.

1. temperatureThe solution was cooled to 0° C.
2. customcarefully quenched with ice chips
3. custompartitioned between water (15 mL) and EtOAc (150 mL)
4. extractionThe aqueous layer was extracted with 3×30 mL DCM
5. dry with materialThe combined organics were dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated