反应详情

A solution of catechol (5.5 g) and 4-(trifluoromethyl)acetophenone (10.3 g) in toluene (150 ml) containing a catalytic amount (0.2 g) of p-toluenesulphonic acid monohydrate was heated under reflux for 3 days. Water produced in the condensation was separated by means of a Dean-Stark trap. After removal of the solvent under reduced pressure, the residue was purified by chromatography on silica gel using methylene chloride as eluant. Pure 2-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-benzodioxole was obtained as a colourless oil (10.8 g, 77%).

1. temperaturewas heated
2. temperatureunder reflux for 3 days
3. customwas separated by means of a Dean-Stark trap
4. customAfter removal of the solvent under reduced pressure
5. customthe residue was purified by chromatography on silica gel