反应详情

温度

20 °C

To a cooled, stirred solution of 25% sodium methoxide (1200 ml, 5.55 mole) was added a slurry of 200 g (1.85 mole) of propionamidine hydrochloride in 300 ml of methanol. Next, 244 g (1.85 mole) of dimethyl malonate was added and the mixture was permitted to warm to about 20° C., after which it was stirred for 16 hours. The mixture was evaporated in vacuo and water (about 2 l) was added. This mixture was neutralized with concentrated hydrochloric acid to provide a white precipitate which was separated by filtration to provide 230 g (96%) of 4,6-dihydroxy-2-ethylpyrimidine, m.p. 312°-215° C. The structural assignment was confirmed by infrared and nuclear magnetic resonance spectral analyses.

1. customThe mixture was evaporated in vacuo and water (about 2 l)
2. additionwas added
3. customto provide a white precipitate which
4. customwas separated by filtration