反应详情

温度

50 °C

To a 3-L three-necked round-bottom flask equipped with an overhead stirrer, condenser, and a nitrogen/thermocouple unit was added methyl p-formylbenzoate (82.08 g, 0.50 mole), malonic acid (104.06 g, 1.00 mole), and pyridine (200 mL). Stirring was started followed by heating to 50° C. for 75 minutes. By this time, a sizable amount of solids had formed and to this mixture was added piperidine (7.5 mL, 0.076 mole) and the temperature raised to 80° C. After another one hour at 80° C., the temperature was raised to 115° C. After another 2.5 hours at this temperature, heating was stopped and the mixture allowed to cool before pouring into water (2 L). To the aqueous mixture was carefully added concentrated HCI (250-300 mL) until the mixture became acidic. The mixture was filtered, and the solids washed with fresh water (1 L) before being suction dried. A yield of 96.83 g (93.9 percent) of white solids was obtained. Proton nmr (DMSO-d6) delta: 7.95 (2H, d); 7.80 (2H, d); 7.60 (1H, d); 6.62 (1H, d); 3.82 (3H, s).

1. customTo a 3-L three-necked round-bottom flask equipped with an overhead stirrer, condenser
2. customBy this time, a sizable amount of solids had formed and to this mixture
3. temperaturethe temperature raised to 80° C
4. temperaturethe temperature was raised to 115° C
5. waitAfter another 2.5 hours at this temperature
6. temperatureheating
7. temperatureto cool
8. additionTo the aqueous mixture was carefully added
9. concentrationconcentrated HCI (250-300 mL) until the mixture
10. filtrationThe mixture was filtered
11. washthe solids washed with fresh water (1 L)
12. customdried