反应详情

A mixture of 580 g (5 moles) of hex-3-ene-2,5-diol, 3 g of p-toluenesulfonic acid, 360 g (5 moles) of n-butanal and 1 l of toluene was refluxed, and the resulting water of reaction (108 ml) was removed in the course of 3 h. Thereafter, the mixture was left to cool to room temperature, 10 ml of a 25% strength aqueous sodium hydroxide solution were added, the mixture was washed neutral with a little water and the toluene was removed under reduced pressure at from 50° to 60° C. The residue obtained was distilled under 0.1 mbar to give 681 g (4 moles) of 2-propyl-4,7-dimethyl-4,7-dihydro-1,3-dioxepin of boiling point 70° C./0.1 mbar.

1. temperaturewas refluxed
2. customwas removed in the course of 3 h
3. waitThereafter, the mixture was left
4. addition10 ml of a 25% strength aqueous sodium hydroxide solution were added
5. washthe mixture was washed neutral with a little water
6. customthe toluene was removed under reduced pressure at from 50° to 60° C
7. customThe residue obtained
8. distillationwas distilled under 0.1 mbar