反应详情

温度

80 °C

Diethyl 1,6-dihydro-5-nitro-6-oxo-2,3-pyridinedicarboxylate (26.23 g, 0.092 mol) is partially dissolved under N2 atmosphere in 250 mL of phosphorous oxychloride and the mixture is heated to 80° C. for 15 hours. The mixture is cooled and concentrated and the resulting oil dissolved in ethyl acetate and washed with water, 10% K2CO3 and brine. The organic layer is dried over MgSO4, filtered and the solvent removed to yield a solid which is recrystallized from absolute ethanol/water to give 20.65 g of the product as a brown solid in 73.9% yield, having a melting point of 84.5°-86° C.

1. temperatureThe mixture is cooled
2. concentrationconcentrated
3. dissolutionthe resulting oil dissolved in ethyl acetate
4. washwashed with water, 10% K2CO3 and brine
5. dry with materialThe organic layer is dried over MgSO4
6. filtrationfiltered
7. customthe solvent removed
8. customto yield a solid which
9. customis recrystallized from absolute ethanol/water