反应详情

5.5 g (0.05 mol) of 2-amino-3-hydroxypyridine are introduced into a three-necked flask and the system is placed under argon. 100 ml of anhydrous tetrahydrofuran (THF) are added. 12.15 g (0.075 mol) of 1,1-carbonyldiimidazole are then introduced. The mixture is heated to reflux for 5 hours (under argon). The THF is then evaporated off. The residue is taken up with dichloromethane. Washes of the organic phase are performed with NaOH solution (5%) (6×150 ml); the cyclized product passes into the aqueous phase and is precipitated at a pH in the region of 5 (by adding 2N hydrochloric acid solution). The product is filtered off and stored in a desiccator.

1. temperatureThe mixture is heated
2. temperatureto reflux for 5 hours (under argon)
3. customThe THF is then evaporated off
4. customis precipitated at a pH in the region of 5 (by adding 2N hydrochloric acid solution)
5. filtrationThe product is filtered off
6. customstored in a desiccator