反应详情

3-Oxo-2-(3-trifluoromethyl-pyrazol-1-yl)-butyric acid benzyl ester (800 mg, 2.452 mmol), EtOH (12.30 ml) and hydrazine (0.231 ml, 7.36 mmol) are stirred at 50° C. for hour. The volatiles are removed in vacuo yielding a wet solid which is added to ammonium chloride (sat. aq. 100 ml) and the product is extracted into EtOAc (2×100 ml). The combined organic extracts are washed with brine, dried over Na2SO4, and concentrated in vacuo to give a pale yellow solid. The crude product is purified by ISCO combiflash chromatography, eluting with 0 to 100% (EtOAc/Iso-hexane) on a 24 g SiO2-column to afford the title compound as an orange oil; MS: m/z 233.09 [M+H]+.

1. customThe volatiles are removed in vacuo
2. customyielding a wet solid which
3. extractionthe product is extracted into EtOAc (2×100 ml)
4. washThe combined organic extracts are washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated in vacuo
7. customto give a pale yellow solid
8. customThe crude product is purified by ISCO combiflash chromatography
9. washeluting with 0 to 100% (EtOAc/Iso-hexane) on a 24 g SiO2-column