反应详情

To a refluxing mixture of 2,4-dichloro-5-(3-fluoropyridin-2-yl)benzoic acid (Preparation 27A, 159 g, 0.554 mol), ethyl 5-amino-1-phenyl-1H-pyrazole-3-carboxylate (154 g, 0.665 mol), N,N-diisopropylethylamine (215 g, 1.66 mol) and 2-methyltetrahydrofuran (4.8 L), was added propylphosphonic anhydride solution (989 mL, 1.66 mol, >50% by weight in EtOAc) and the reaction maintained at reflux for 6 hours. After cooling to room temperature, the reaction was diluted with water (6 L) and extracted with 2-methyltetrahydrofuran (2×1.5 L). The combined organic layers were concentrated in vacuo to provide a slurry which was filtered and the solid washed with ethyl acetate (3×200 mL) to give the title compound as a white solid (215 g, 79%).

1. temperaturethe reaction maintained
2. temperatureat reflux for 6 hours
3. extractionextracted with 2-methyltetrahydrofuran (2×1.5 L)
4. concentrationThe combined organic layers were concentrated in vacuo
5. customto provide a slurry which
6. filtrationwas filtered
7. washthe solid washed with ethyl acetate (3×200 mL)