反应详情

To a suspension of the product obtained in Step 1 (50 g) in 500 ml of phosphorus oxychloride N,N-dimethylaniline (30 g) was dropwise added at room temperature, the mixture was refluxed for two hours, excess phosphorus oxychloride was removed by distillation under normal pressure, and the black oil left was dissolved in 200 ml of chloroform. This solution was slowly poured into 200 ml of ice-cooled saturated sodium bicarbonate solution, the chloroform layer was collected after thorough mixing, and the aqueous layer was again extracted with 200 ml of fresh chloroform. The combined organic layers were washed with 100 ml of saturated sodium chloride solution and dried over anhydrous sodium sulfate. The dried solution was concentrated under reduced pressure to about 50 ml, and 100 ml of n-hexane was added to this concentrate, giving 49 g of the objective compound as colorless crystals.

1. additionwas dropwise added at room temperature
2. temperaturethe mixture was refluxed for two hours
3. customexcess phosphorus oxychloride was removed by distillation under normal pressure
4. waitthe black oil left
5. dissolutionwas dissolved in 200 ml of chloroform
6. additionThis solution was slowly poured into 200 ml of ice-
7. temperaturecooled saturated sodium bicarbonate solution
8. customthe chloroform layer was collected after thorough mixing
9. extractionthe aqueous layer was again extracted with 200 ml of fresh chloroform
10. washThe combined organic layers were washed with 100 ml of saturated sodium chloride solution
11. dry with materialdried over anhydrous sodium sulfate
12. concentrationThe dried solution was concentrated under reduced pressure to about 50 ml, and 100 ml of n-hexane
13. additionwas added to this concentrate