反应详情

5 g of anhydrous tin chloride was added to 100 g of safrole. Hydrochloric acid gas was passed though the mixture under cooling with ice for 1.5 hours. 2 l of ethyl acetate was added to the reaction mixture, followed by the dissolution. The obtained mixture was washed with water twice, dried over anhydrous sodium sulfate and distilled to remove the solvent. The residue was purified by silica gel column chromatography (hexane/benzene=10:1) to obtain 41.7 g of 5-(2-chloropropyl)-1,3-benzodioxole as a colorless oil. This oil was dissolved in 150 ml of ethanol, followed by the addition of 48 g of thiourea. The obtained mixture was heated under reflux for 7 days, cooled and filtered. A solution of 12.8 g of sodium hydroxide in 100 ml of water was added to the filtrate. The obtained mixture was heated under reflux for 2 hours, cooled and acidified with dilute sulfuric acid. 1 l of benzene and 1 l of water were added to the mixture to carry out the phase separation. The benzene layer was washed with water twice, dried over anhydrous sodium sulfate and distilled to remove the solvent. The residue was purified by silica gel column chromatography (hexane/benzene=10:1) to obtain 8.5 g of the title compound as a colorless oil.

1. temperatureunder cooling with ice for 1.5 hours
2. dissolutionfollowed by the dissolution
3. washThe obtained mixture was washed with water twice
4. dry with materialdried over anhydrous sodium sulfate
5. distillationdistilled
6. customto remove the solvent
7. customThe residue was purified by silica gel column chromatography (hexane/benzene=10:1)