反应详情

To the solution of (S)-tert-butyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)pyrrolidine-1-carboxylate (compound 18a, 5.0 g, 12.2 mmol) in xylene (75 ml) were added ammonium acetate (23.4 g, 304 mmol) and acetic acid (5 ml) at room temperature. The reaction mixture was placed in an oil bath and heated to 160° C. with water being azeotroped into a Dean-Stark trap. After 3 hours, the resulting mixture was cooled to room temperature and then extracted with ethyl acetate and distillated water. The organic layer was dried over MgSO4, filtered, and concentrated under reduced pressure to give a crude product, which was purified with column chromatography (100% ethyl acetate) to yield the pure product 19a (4.4 g).

1. customThe reaction mixture was placed in an oil bath
2. customazeotroped into a Dean-Stark trap
3. extractionextracted with ethyl acetate and distillated water
4. dry with materialThe organic layer was dried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customto give a crude product, which
8. customwas purified with column chromatography (100% ethyl acetate)