反应详情

A suspension of 2-ethoxycarbonyl-5-bromo-3-chromanone (300 mg, 1 mMol) in methanol (5 mL) and 10% hydrochloric acid (3 mL) was heated at reflux for 2 hours. All of the solid had not dissolved; therefore, trifluoroacetic acid (1 mL) was added, and heating was continued for 18 hours. The reaction mixture was diluted with water and extracted well with diethyl ether. The ether phases were combined, dried over sodium sulfate, and concentrated in vacuo to give a yellow glass. Purification by flash chromatography (1:1 hexane:ether) gave the title compound as a light yellow glass (120 mg, 53%).

1. temperaturewas heated
2. temperatureat reflux for 2 hours
3. dissolutionAll of the solid had not dissolved
4. temperatureheating
5. extractionextracted well with diethyl ether
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated in vacuo
8. customto give a yellow glass
9. customPurification by flash chromatography (1:1 hexane:ether)