反应详情

1.5 ml of sulphuric acid (100% strength) are added to a solution of 7.69 g (40 mmol) of 3-carboxymethylchroman in 150 ml of methanol and the whole is boiled under reflux for 3 hours. After cooling, the reaction mixture is concentrated by evaporation in vacuo. The residue is dissolved in diethyl ether and washed, while cold, with water, sodium hydrogen carbonate and again with water. The combined organic phases are dried over sodium sulphate and concentrated by evaporation in vacuo. 8.08 g (98%) of 3-methoxycarbonylmethylchroman are obtained in the form of a pale yellow oil.

1. temperatureunder reflux for 3 hours
2. temperatureAfter cooling
3. concentrationthe reaction mixture is concentrated by evaporation in vacuo
4. dissolutionThe residue is dissolved in diethyl ether
5. washwashed
6. dry with materialThe combined organic phases are dried over sodium sulphate
7. concentrationconcentrated by evaporation in vacuo