反应详情

To a mixture of 3.4 g 5-Hydroxy-2H-pyrazole-3-carboxylic acid ethyl ester and 3 g K2CO3 in 50 ml acetonitrile, 4 g 1-(2-Bromo-ethoxy)-2-methoxy-ethane were added. After stirring for 1 h at RT the reaction was heated to 50° C. for 4 h. Then 50 ml of water were added and the mixture was extracted with DCM (3×100 ml). The combined organic layers were dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified by chromatography on silica eluting with a DCM/MeOH gradient. Yield: 1 g.

1. additionwere added
2. temperaturewas heated to 50° C. for 4 h
3. extractionthe mixture was extracted with DCM (3×100 ml)
4. dry with materialThe combined organic layers were dried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by chromatography on silica eluting with a DCM/MeOH gradient