反应详情

A mixture of 29.4 g (0.3 mol) of sulphuric acid, 50 ml of water and 2 ml of "Aliquat" 336 (tricaprylmethylammonium chloride) was added to a solution of 27 g (0.1 mol) of 3-bromo-4-trifluoromethoxybenzyl alcohol in 250 ml of methylene chloride at room temperature. Thereafter, 9.7 g (0.033 mol) of potassium dichromate were added to the reaction mixture, and the temperature was kept at approx. 25° C. for 2 hours by slight cooling. After 100 ml of water had been added to the mixture, the organic phase was separated off and the water was once again extracted by shaking with 100 ml of methylene chloride. The organic phases were washed twice with 100 ml of water, then once with 100 ml of saturated sodium bicarbonate solution, and once again with 100 ml of water, dried over sodium sulphate, and concentrated by evaporation in vacuo. The residue was distilled. In this manner, 20.4 g (75.8% of theory) of 3-bromo-4-trifluoromethoxybenzaldehyde were obtained as a colorless oil of boiling point 97° C./10 mm Hg. ##STR23##

1. customthe organic phase was separated off
2. extractionthe water was once again extracted
3. washThe organic phases were washed twice with 100 ml of water
4. dry with materialonce with 100 ml of saturated sodium bicarbonate solution, and once again with 100 ml of water, dried over sodium sulphate
5. concentrationconcentrated by evaporation in vacuo
6. distillationThe residue was distilled