반응 #55507

반응 방정식

2,4-diamino-6-[3,6-dihydro-1(2H)-pyridyl]-pyrimidine-3-oxide

chloroformic acid methyl ester

sodium hydroxide

→

methyl 2-amino-6-[3,6-dihydro-1(2H)-pyridyl]-4-pyrimidinecarbamate-3-oxide

용매

methylene chloride

methylene chloride

water

반응 조건

후처리

1. 1
   온도While cooling
2. 2
   workup.ADDITIONthere are simultaneously added dropwise 8 ml
3. 3
   workup.ADDITIONAfter completion of the addition
4. 4
   workup.STIRRINGthe mixture is stirred for a further 1 hour
5. 5
   여과the residue is subsequently filtered off
6. 6
   기타The two phases obtained
7. 7
   기타are separated
8. 8
   workup.ADDITIONthe organic phase is treated for 1 hour
9. 9
   workup.STIRRINGwhile stirring at 0° C. with 150 ml
10. 10
    기타The mixture obtained
11. 11
    workup.ADDITIONis treated with 20 ml
12. 12
    기타of methanol and the two phases are separated
13. 13
    추출The aqueous phase is extracted twice with 200 ml
14. 14
    건조of methylene chloride and the combined organic extracts are dried over sodium sulfate
15. 15
    기타By evaporation of the solvent there

실험 절차

20 G. of 2,4-diamino-6-[3,6-dihydro-1(2H)-pyridyl]-pyrimidine-3-oxide are suspended and stirred in 140 ml. of methylene chloride and 120 ml. of water. While cooling, there are simultaneously added dropwise 8 ml. of chloroformic acid methyl ester in 20 ml. of methylene chloride and sufficient 28% sodium hydroxide so that the pH value is held between 7.0 and 7.5. After completion of the addition, the mixture is stirred for a further 1 hour and the residue is subsequently filtered off. The two phases obtained are separated and the organic phase is treated for 1 hour while stirring at 0° C. with 150 ml. of 1-N sodium hydroxide. The mixture obtained is treated with 20 ml. of methanol and the two phases are separated. The aqueous phase is extracted twice with 200 ml. of methylene chloride and the combined organic extracts are dried over sodium sulfate. By evaporation of the solvent there is obtained pure methyl 2-amino-6-[3,6-dihydro-1(2H)-pyridyl]-4-pyrimidinecarbamate-3-oxide having a melting point of 174°-176° C.

출처