反应详情

温度

100 °C

A mixture of 7-(2-tetrahydropyranyloxy)heptanal (22 g.) and 1-morpholinocyclopentene, i.e. the morpholine enamine of cyclopentanone, (21.4 g.) in benzene (25 ml.) was heated under reflux for 12 hours under nitrogen, and the water liberated was continuously removed with a Dean and Stark head. Benzene (10 ml.) and then, dropwise, 18% hydrochloric acid (28 ml.) were added and the mixture was stirred for 2 hours. The organic layer was separated and evaporated. Concentrated hydrochloric acid (72 ml.) and butanol (300 ml.) were added to the residue. The mixture was heated at 100° C. for 1 hour, and then the solution was concentrated to give an oil. Diethyl ether was added, and the ether solution was washed with aqueous sodium bicarbonate and then water, and dried over sodium sulphate. The solvent was evaporated and the residue was distilled under reduced pressure to give 2-(7-hydroxyheptyl)cyclopent-2-en-1-one (11.7 g.), b.p. 125°-170° C/0.15 mm.Hg, nD25 1.490, μmax 228mμ (ethanol).

1. temperaturewas heated
2. temperatureunder reflux for 12 hours under nitrogen
3. customthe water liberated was continuously removed with a Dean and Stark head
4. additionBenzene (10 ml.) and then, dropwise, 18% hydrochloric acid (28 ml.) were added
5. customThe organic layer was separated
6. customevaporated
7. additionConcentrated hydrochloric acid (72 ml.) and butanol (300 ml.) were added to the residue
8. concentrationthe solution was concentrated
9. customto give an oil
10. washthe ether solution was washed with aqueous sodium bicarbonate
11. dry with materialwater, and dried over sodium sulphate
12. customThe solvent was evaporated
13. distillationthe residue was distilled under reduced pressure