反应详情

14.9 g (0.1 mol) of 5-methyl-2,3,4,5-tetrahydrobenzoxepin-5-ol, 300 ml of toluene and a spatula tip of para-toluenesulphonic acid are charged to a 1 litre reactor equipped with a Denan and Stark apparatus. The combined solution is brought to reflux for 2 hours, the water being removed as it is formed. The reaction mixture is then neutralized with a 5% aqueous sodium bicarbonate solution and the organic solution is washed with water. The organic phase is subsequently dried over anhydrous sodium sulphate and concentrated under reduced pressure. 16 g of the title compound are obtained, which compound is purified by distillation, B.p. (2.5 mm Hg)=80-90° C. 10 g of a colourless liquid are obtained.

1. temperatureto reflux for 2 hours
2. customthe water being removed as it
3. customis formed
4. washthe organic solution is washed with water
5. dry with materialThe organic phase is subsequently dried over anhydrous sodium sulphate
6. concentrationconcentrated under reduced pressure