反应详情

A mixture of 3-chloro-5-nitrobenzisothiazole (5.3 g, mmol), 3,5-dimethylpyrazole (2.40 g, 25.0 mmol) and pyridine is stirred overnight at reflux, cooled to room temperature and diluted with ethyl acetate. The resultant mixture is filtered and the filtrate is washed with three portions of 10% hydrochloric acid and one portion of water. The organic layer is dried over anhydrous magnesium sulfate and concentrated in vacuo to afford the title compound (2.85 g, 43.8%) which is identified by NMR spectral analysis.

1. temperatureat reflux
2. filtrationThe resultant mixture is filtered
3. washthe filtrate is washed with three portions of 10% hydrochloric acid and one portion of water
4. dry with materialThe organic layer is dried over anhydrous magnesium sulfate
5. concentrationconcentrated in vacuo