Phosphorus oxychloride → 5-Chloro-1,3-dimethyl-1H-dipyrazolo[1,5-a:4',3'-e]pyrazine-6-carboxylic acid, ethyl ester
反応式
O[C:2]1[C:3]2[N:4]([N:13]=[CH:14][C:15]=2[C:16]([O:18][CH2:19][CH3:20])=[O:17])[C:5]2[N:10]([CH3:11])[N:9]=[C:8]([CH3:12])[C:6]=2[N:7]=1.P(Cl)(Cl)([Cl:23])=O>CN(C)C=O>[Cl:23][C:2]1[C:3]2[N:4]([N:13]=[CH:14][C:15]=2[C:16]([O:18][CH2:19][CH3:20])=[O:17])[C:5]2[N:10]([CH3:11])[N:9]=[C:8]([CH3:12])[C:6]=2[N:7]=1参加物
4
実験手順
92.5 gms. of 5-hydroxy-1,3-dimethyl-1H-dipyrazolo[1,5-a:4',3'-e]pyrazine-6-carboxylic acid, ethyl ester, together with 300 ml. of phosphorus oxychloride and 3 ml. of dimethylformamide are refluxed for 5 hours. After distilling off the phosphorus oxychloride, the reaction mixture is poured onto ice and the crude 5-chloro-1,3-dimethyl-1H-dipyrazolo[1,5-a:4',3'-e]pyrazine-6-carboxylic acid ethyl ester, is filtered under suction, then recrystallized from acetone, yield 83 gms. of white crystals, m.p. 130°-132°.