反应详情

A mixture of 3-bromo-N-(2-hydroxyphenyl)-4-methylbenzamide (550 mg, 1.8 mmol), p-toluenesulfonic acid (2.4 g, 12.7 mmol) in toluene (50 mL) was refluxed for 4 h, cooled to rt, and filtered through a Celite pad. The filtrate was evaporated to dryness and the residue was purified by flash chromatography on silica gel using a gradient of EtOAc:hexane (0 to 30 min: 0 to 15% EtOAc) to afford 2-(3-bromo-4-methylphenyl)-1,3-benzoxazole as a colorless solid. MS (ESI) 288 (M+H)+.

1. temperaturewas refluxed for 4 h
2. filtrationfiltered through a Celite pad
3. customThe filtrate was evaporated to dryness
4. customthe residue was purified by flash chromatography on silica gel using a gradient of EtOAc