反应详情

A mixture of guanine 3 (30 g, 0.199 mol), acetic anhydride (450 ml), and acetic acid (300 ml) was heated to reflux. Phosphoric acid (85.5%, 1.5 ml) was added to the mixture and the mixture then refluxed for 15 hours. Some product precipitated on the side of flask. Solvents were removed under reduced pressure (water aspirator) to dryness. After cooling, the resulting solid was collected, and then washed twice with water (30 ml) and methanol (20 ml) to give diacetylguanine (42.5 g, 91%). The filtrate (water and methanol) obtained above was concentrated to near dryness to give additional 4 (1.7 g, 3.6%). The total yield of 4 was 44.26 g (94.6%).

1. temperaturewas heated to reflux
2. temperaturethe mixture then refluxed for 15 hours
3. customSome product precipitated on the side of flask
4. customSolvents were removed under reduced pressure (water aspirator) to dryness
5. temperatureAfter cooling
6. customthe resulting solid was collected
7. washwashed twice with water (30 ml) and methanol (20 ml)