反应详情

A solution of concentrated sulphuric acid (6 mL) in distilled water (75 mL) was added to 5-bromo-2-methylaniline (1 g, 5.38 mmol). The resultant suspension was heated to 90° C. and stirred for 4.5 h. The reaction mixture was then cooled using an ice bath and a solution of sodium nitrite (384 mg, 5.57 mmol) in water (5 mL) was added to the reaction mixture at 0° C. The reaction was then allowed to warm to ambient temperature. The reaction mixture was then added to a solution of concentrated sulphuric acid (6 mL) in water (75 mL) which had been preheated to 90° C. The reaction mixture was stirred for 1 h at 90° C. and allowed to cool, on standing, overnight. A precipitate was observed in the reaction mixture. The precipitate was collected by filtration, washed with water, and dried in a vacuum oven to afford 5-bromo-2-methylphenol as a brown solid (510 mg, 2.73 mmol, 51%). M.S. (ESI) (m/z) 185, 187[M−H]−

1. temperatureThe reaction mixture was then cooled
2. customhad been preheated to 90° C
3. stirringThe reaction mixture was stirred for 1 h at 90° C.
4. temperatureto cool, on standing, overnight
5. filtrationThe precipitate was collected by filtration
6. washwashed with water
7. customdried in a vacuum oven