反应详情

10 g of polyphosphoric acid is added to a solution of 2 g (3 mmol) of ethyl 4-(4-(4-(tert-butoxycarbonyl)piperazin-1-yl)phenyl)-3-(thiophen-2-yl)-6-(2,3,6-trifluorophenyl)-4,7-dihydro-1H-pyrazolo[3,4-b]pyridine-5-carboxylate in xylene (20 ml). The reaction mixture is carried at 160° C. for 36 hours. After returning to room temperature, the reaction medium is poured over crushed ice. Saturated sodium bicarbonate solution is added until the reaction medium is neutralized and then the product is extracted with ethyl acetate. The organic phases are combined, dried on magnesium sulfate and concentrated. The residue is purified by silica gel chromatography (eluent: 88:12 dichloromethane/methanol) to yield 50 mg (3%) of 8-(piperazin-1-yl)-1-(thiophen-2-yl)-5-(2,3,6-trifluorophenyl)indeno[1,2-d]pyrazolo[3,4-b]pyridin-6(3H)-one in the form of a pinkish solid.

1. customAfter returning to room temperature
2. additionthe reaction medium is poured
3. customover crushed ice
4. extractionthe product is extracted with ethyl acetate
5. customdried on magnesium sulfate
6. concentrationconcentrated
7. customThe residue is purified by silica gel chromatography (eluent: 88:12 dichloromethane/methanol)