反应详情

7.8 g (23 mmol) of the compound from Example 5 are heated to 75° C. in 20 ml of phosphorus oxychloride. After a clear solution has formed, the mixture is concentrated in vacuo, the residue is dissolved in ethyl acetate, and the solution is poured into ice water and stirred vigorously. The aqueous phase is extracted twice with ethyl acetate, the combined organic phases are dried and the solvent is stripped off. 5.78 g (71%) of colorless crystals of m.p.: 142° C. crystallize from ether.

1. customAfter a clear solution has formed
2. concentrationthe mixture is concentrated in vacuo
3. dissolutionthe residue is dissolved in ethyl acetate
4. additionthe solution is poured into ice water
5. extractionThe aqueous phase is extracted twice with ethyl acetate
6. customthe combined organic phases are dried
7. custom5.78 g (71%) of colorless crystals of m.p.: 142° C. crystallize from ether