反应详情

using a Dan-Stark separator, 2,3-diaminopyridine (54.6 g; 0.5 mol) and glycolic acid (38 g; 0.5 mol) in 700 ml of mesitylene were boiled under reflux until the calculated amount of water had separated off. The mixture was then cooled to room temperature, and the resulting precipitate was filtered off with suction and, with addition of activated carbon, boiled in 800 ml of water for 15 min. The hot suspension was filtered and once more cooled to room temperature, and the colourless crystals that precipitated out were filtered off with suction and dried. Yield: 56.4 g (75%).

1. customhad separated off
2. filtrationthe resulting precipitate was filtered off with suction and, with addition of activated carbon
3. filtrationThe hot suspension was filtered
4. temperatureonce more cooled to room temperature
5. customthe colourless crystals that precipitated out
6. filtrationwere filtered off with suction
7. customdried