反应详情

A solution of methanesulfonic acid (20 mL, 0.31 mol) in phosphorus pentoxide (5.00 g, 35.2 mmol) was heated at 100° C. The mixture was stirred at the same temperature, while powdery 2-[[1-(2-pyridinyl)-1H-pyrazol-5-yl]amino]benzoic acid (1.94 g, 6.92 mmol) was added in small portions. The reaction mixture was heated and stirred at the same temperature for 10 minutes. The mixture was allowed to cool to room temperature, and iced water was added thereto. The solution was made basic by the addition of an aqueous sodium hydroxide solution, and the organic matter was extracted with ethyl acetate. The extract was washed with saturated brine and water, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue thus obtained was purified by silica gel column chromatography (chloroform:methanol=99:1) to give the title compound (1.35 g, 74% yield).

1. additionwas added in small portions
2. temperatureThe reaction mixture was heated
3. extractionthe organic matter was extracted with ethyl acetate
4. washThe extract was washed with saturated brine and water
5. dry with materialdried over anhydrous magnesium sulfate
6. customthe solvent was evaporated under reduced pressure
7. customThe residue thus obtained
8. customwas purified by silica gel column chromatography (chloroform:methanol=99:1)