反应详情

A mixture of 7-butoxy-1,2-dihydro-3-naphthoic acid (0.9 g) and powdery sulfur (0.25 g) is heated at 200°-210° C. for 35 minutes. After cooling, the mixture is dissolved in ethyl ether (200 ml). The solution is extracted with a 0.5N aqueous solution of sodium hydroxide. The aqueous layer is made acid with concentrated hydrochloric acid, and the precipitating crystals are collected by filtration. The crystals are dissolved in acetone, and insolubles are filtered off. The filtrate is concentrated under reduced pressure to allow crystals to precipitate. To the precipitates is added (100 ml), and the precipitates are collected by filtration to afford 6-butoxy-2-naphthoic acid

1. temperatureis heated at 200°-210° C. for 35 minutes
2. temperatureAfter cooling
3. extractionThe solution is extracted with a 0.5N aqueous solution of sodium hydroxide
4. filtrationthe precipitating crystals are collected by filtration
5. dissolutionThe crystals are dissolved in acetone
6. filtrationinsolubles are filtered off
7. concentrationThe filtrate is concentrated under reduced pressure
8. customto precipitate
9. additionTo the precipitates is added (100 ml)
10. filtrationthe precipitates are collected by filtration