反应详情

温度

250 °C

21.8 g (3.61 mmol) of 2-[(6-Methyl-pyridin-2-ylamino)-methylene]-malonic acid diethyl ester was dissolved in 300 mL of diphenyl ether and the solution was heated at 250° C. After 2.5 h the solution was cooled to rt and 50 mL of hexane was added. The mixture was filtered and the solid washed with hexane to yield 18.5 g of -Methyl-4-oxo-1,4-dihydro-[1,8]naphthyridine-3-carboxylic acid ethyl ester as a brown solid.

1. temperatureAfter 2.5 h the solution was cooled to rt
2. filtrationThe mixture was filtered
3. washthe solid washed with hexane