反应详情

To a suspension of 1.0 mole of phosphorous pentoxide in 300 ml. of dry chloroform is added dropwise with stirring a solution of 0.5 mole of N-acryloylalanine ethyl ester. The reaction mixture is heated at gentle reflux for 5 hours and then cooled. To the cooled mixture is added with rapid stirring 750 ml. of 20% aqueous potassium hydroxide. After stirring at room temperature for 1 hour, the chloroform layer is separated and the aqueous layer extracted with 2 × 200 ml. of chloroform. The combined chloroform extracts are washed with water, dried over sodium sulfate, and concentrated in vacuo to yield 5-ethoxy-4-methyl-2-vinyloxazole.

1. temperatureThe reaction mixture is heated
2. temperatureat gentle reflux for 5 hours
3. temperaturecooled
4. additionTo the cooled mixture is added
5. stirringAfter stirring at room temperature for 1 hour
6. customthe chloroform layer is separated
7. extractionthe aqueous layer extracted with 2 × 200 ml
8. washThe combined chloroform extracts are washed with water
9. dry with materialdried over sodium sulfate
10. concentrationconcentrated in vacuo