Dichloromethane → methyl 5-(3-pyrrolin-1-yl)-2-oxo-2H-[1,2,4]-oxadiazolo[2,3-a]pyrimidine-7-carbamate

反応式

[N:1]1([C:6]2[N:11]=[C:10]([NH:12][C:13](OC)=[O:14])[N+:9]([O-:17])=[C:8]([NH:18][C:19]([O:21][CH3:22])=[O:20])[CH:7]=2)[CH2:5][CH:4]=[CH:3][CH2:2]1.C(Cl)Cl.[OH-].[Na+]>O>[N:1]1([C:6]2[CH:7]=[C:8]([NH:18][C:19]([O:21][CH3:22])=[O:20])[N:9]3[O:17][C:13](=[O:14])[N:12]=[C:10]3[N:11]=2)[CH2:5][CH:4]=[CH:3][CH2:2]1

参加物

実験手順

4.5 G. of dimethyl 6-(3-pyrrolin-1-yl)-2,4-pyrimidine-dicarbamate-3-oxide are suspended in a mixture of 200 ml. of methylene chloride and 200 ml. of water. The suspension is adjusted with concentrated sodium hydroxide to pH 12.5 and stirred at this pH for 3 hours. The two phases are then separated and the aqueous phase is adjusted to pH 3 with concentrated hydrochloric acid. The separated white precipitate is filtered off, pre-dried and recrystallized from a mixture of methylene chloride and methanol, there being obtained pure methyl 5-(3-pyrrolin-1-yl)-2-oxo-2H-[1,2,4]-oxadiazolo[2,3-a]pyrimidine-7-carbamate, having a melting point of 230°-234° C. (decomposition).