Hydrogen iodide → 4,8-Dianilino Pyrimido-Pyrimidine
Reaktionsgleichung
[P](I)I.Cl[C:5]1[N:6]=[C:7]([NH:23][C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)[C:8]2[N:13]=[C:12](Cl)[N:11]=[C:10]([NH:15][C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=3)[C:9]=2[N:22]=1.I>>[NH:23]([C:7]1[C:8]2[N:13]=[CH:12][N:11]=[C:10]([NH:15][C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=3)[C:9]=2[N:22]=[CH:5][N:6]=1)[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1Komponenten
4
Versuchsvorschrift
12 gm. of phosphorus diiodide (P2I4) were added in small portions to a suspension, heated on a steam bath, of 3.8 gm. (0.01) 2,6-dichloro-4,8-dianilino pyrimido-pyrimidine in 40 cc. hydrogen iodide (d=1.7) in the course of about half an hour. Heating was continued for one hour. The mixture was then cooled and the precipitated crystals were filtered off on a vacuum filter. The precipitate was extracted with 200 cc. of hot dioxane. 2.8 gm. of red, brilliant rhombic crystals remained after extraction. The yield was about 90% of the theoretical yield. The crystals were twice recrystallized from dimethyl formamide, whereby very slightly yellowish, small needles having a melting point of 255-256° C. were obtained.