反应详情

124 g (0.8 mol) of 2-dimethylamino-4,6-dihydroxypyrimidine are stirred with 800 cc of 1N sodium hydroxide solution at 60° for 1 hour. 171 g (0.8 mol) of p-toluenesulphonic acid-n-propyl ester are added dropwise at 90° over the course of 1 hour and the pH is kept at 8-8.5 by the dropwise addition of 1N sodium hydroxide solution. The mixture is stirred at 90° for 16 hours, cooled to 5°, neutralized with glacial acetic acid and allowed to stand at room temperature for 6 hours. The precipitated crystals are subsequently filtered by suction, washed with water, dissolved in approximately 700 cc of chloroform, dried over sodium sulphate and evaporated to dryness in a vacuum. The residue is decomposed with 500 cc of petroleum ether, filtered by suction and recrystallized from benzene, washed with petroleum ether and dried at 60° in a high vacuum. M.P.: 194°-195°.

1. temperaturecooled to 5°
2. waitto stand at room temperature for 6 hours
3. filtrationThe precipitated crystals are subsequently filtered by suction
4. washwashed with water
5. dissolutiondissolved in approximately 700 cc of chloroform
6. dry with materialdried over sodium sulphate
7. customevaporated to dryness in a vacuum
8. filtrationfiltered by suction
9. customrecrystallized from benzene
10. washwashed with petroleum ether
11. customdried at 60° in a high vacuum