反应详情

A reflux condenser equipped with a Dean-Stark water separator was attached to a round bottom flask containing methyl 2-cyclopentanonecarboxylate (2 ml, 16.2 mmol), ethylene glycol (994 μl, 17.8 mmol), p-toluenesulfonic acid monohydrate (139 mg, 0.73 mmol), and benzene (30 ml). The mixture was heated under reflux for 2 hours. To the reaction mixture, triethylamine (0.22 ml) was added and the mixture was concentrated and purified by silica gel column chromatography (elution solvent: ethyl acetate/heptane=1/9, 1/1) to obtain the title compound (2.12 g, yield 70.3%) as a colorless oil.

1. customseparator was attached to a round bottom flask
2. temperatureThe mixture was heated
3. temperatureunder reflux for 2 hours
4. concentrationthe mixture was concentrated
5. custompurified by silica gel column chromatography (elution solvent: ethyl acetate/heptane=1/9, 1/1)