反应详情

温度

0 °C

1.86 g of potassium are initially charged in 120 ml of dry diethyl ether, and 15 ml of EtOH are added slowly. The mixture is cooled to 0° C. 5 g of 2-(2-methoxyethoxy)-4-methyl-5-nitropyridine are dissolved in 15 ml of dry ether and 3 ml of EtOH and added. 27.5 g of diethyl oxalate were dissolved in 100 ml of toluene and, at 0° C., added dropwise over a period of 45 min. The mixture is stirred at room temperature for 24 h. The precipitate is allowed to settle, the mixture is filtered and the precipitate is washed with ether/n-heptane 1:1. The precipitate is dried under high vacuum. This gives ethyl 3-[2-(2-methoxyethoxy)-5-nitropyridin-4-yl]-2-oxopropionate potassium salt as a red solid. (LC-MS protonate form) C13H16N2O7 (312.28), MS (ESI): 313 (M+H+).

1. additionadded dropwise over a period of 45 min
2. filtrationthe mixture is filtered
3. washthe precipitate is washed with ether/n-heptane 1:1
4. customThe precipitate is dried under high vacuum