反应详情

To a mixture of ethyl 7-[cyclopropyl(pyridin-2-ylsulfonyl)amino]-5-(2-methoxyethoxy)indoline-2-carboxylate (1.31 g) and toluene (30 mL) was added manganese (IV) oxide (0.99 g) at room temperature, and the mixture was refluxed for 3 hr. The catalyst was filtered off, and the filtrate was concentrated. The residue was subjected to silica gel column chromatography to give the title compound (1.23 g, yield 94%) as a colorless solid from a fraction eluted with ethyl acetate-hexane (4:1, volume ratio).

1. temperaturethe mixture was refluxed for 3 hr
2. filtrationThe catalyst was filtered off
3. concentrationthe filtrate was concentrated