反应详情

To a solution of ethyl 2-(5-amino-3-phenyl-pyrazol-1-yl)acetate (49 g, 0.17 mol) in pyridine (200 mL) was added acetic anhydride (17.4 g, 0.17 mol) dropwise at 0° C. under an atmosphere of nitrogen. The reaction mixture was stirred at room temperature for 16 h. The reaction mixture was concentrated in vacuo. The residue was diluted with CH2Cl2 and water. The layers were separated and the organic layer was washed with water and brine, dried (MgSO4) and concentrated in vacuo. CH2Cl2 was added to the residue and the solid was collected by filtration, yielding the title compound as a solid (22 g). The mother liquors were concentrated in vacuo and washed with cold CH2Cl2 to yield a second batch of 15 g.

1. concentrationThe reaction mixture was concentrated in vacuo
2. additionThe residue was diluted with CH2Cl2 and water
3. customThe layers were separated
4. washthe organic layer was washed with water and brine
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. additionCH2Cl2 was added to the residue
8. filtrationthe solid was collected by filtration