反应详情

温度

140 °C

119 Parts of 4-chloro-4-(2,2,2-trichloroethyl)-oxetan-2-one and 95.5 parts of guanidine hydrochloride were charged to a reaction flask and heated in an oil bath at 140° C. for 15 minutes. The solid dissolved and HCl gas was evolved. The oil bath temperature was raised to 160° C. and heating was continued for a further 45 minutes. The heat was removed and the reaction mass was stirred until cool and solidified. The solid was stirred with 250 parts of ethyl acetate and filtered. The filtrate was discarded and the solid dissolved in 1000 parts of hot water, treated with charcoal and filtered. The aqueous solution was cooled and neutralised by the addition of saturated sodium acetate solution. The precipitated solid was filtered and washed with water. This crude product was then dissolved in 550 parts of concentrated hydrochloric acid, diluted with 800 parts of water and stirred with 5 parts of charcoal for 20 minutes. The solution was filtered and the product precipitated by the addition of saturated sodium acetate solution to pH 6. The solid was filtered, washed with water and dried in a vacuum oven at 110° C. to give 2-amino-4-(2,2-dichloro-vinyl)-6-hydroxypyrimidine m.p. 245°-248° C. (decomposition).

1. dissolutionThe solid dissolved
2. temperatureThe oil bath temperature was raised to 160° C.
3. temperatureheating
4. customThe heat was removed
5. temperatureuntil cool
6. stirringThe solid was stirred with 250 parts of ethyl acetate
7. filtrationfiltered
8. dissolutionthe solid dissolved in 1000 parts of hot water
9. additiontreated with charcoal
10. filtrationfiltered
11. temperatureThe aqueous solution was cooled
12. additionneutralised by the addition of saturated sodium acetate solution
13. filtrationThe precipitated solid was filtered
14. washwashed with water
15. dissolutionThis crude product was then dissolved in 550 parts of concentrated hydrochloric acid
16. additiondiluted with 800 parts of water
17. stirringstirred with 5 parts of charcoal for 20 minutes
18. filtrationThe solution was filtered
19. customthe product precipitated by the addition of saturated sodium acetate solution to pH 6
20. filtrationThe solid was filtered
21. washwashed with water
22. customdried in a vacuum oven at 110° C.