反应详情

温度

3 °C

A solution of 20 g (64.66 mmol) of 6-Methoxy-3-(4-trifluoromethyl-phenyl)-benzo[d]isothiazole in 150 ml of acetic acid and 75 ml 62% aqueous HBr solution was heated to reflux for 70 h, subsequently cooled and taken up in ice water and extracted with tert-butylmethyleter (3×). The organic phases were washed with saturated sodium hydrogen carbonate solution (3×) and dried (Na2SO4). The residue was suspended in 350 ml boiling CH2Cl2, cooled to 3° C. and filtered to yield 15.8 g (83%) of 3-(4-Trifluoromethyl-phenyl)-benzo[d]isothiazol-6-ol, MS: 295 (M).

1. temperatureto reflux for 70 h
2. temperaturesubsequently cooled
3. extractionextracted with tert-butylmethyleter (3×)
4. washThe organic phases were washed with saturated sodium hydrogen carbonate solution (3×)
5. dry with materialdried (Na2SO4)
6. filtrationfiltered