[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[CH2:12][CH3:13])[NH:8][C:7](=[O:14])[C:6](=[O:15])[NH:5]2.[N+:16]([O-:19])([OH:18])=[O:17]>>[Cl:1][C:2]1[C:3]([N+:16]([O-:18])=[O:17])=[C:4]2[C:9](=[CH:10][C:11]=1[CH2:12][CH3:13])[NH:8][C:7](=[O:14])[C:6](=[O:15])[NH:5]2.[Cl:1][C:2]1[CH:3]=[C:4]2[C:9]([NH:8][C:7](=[O:14])[C:6](=[O:15])[NH:5]2)=[C:10]([N+:16]([O-:19])=[O:17])[C:11]=1[CH2:12][CH3:13]1,4-Dihydro-6-chloro-7-ethylquinoxalin-2,3-dione (2.34 g, 10.4 mmol) was added in small portions over 10 minutes to vigorously stirred concentrated nitric acid (20 ml) at room temperature. The mixture was then heated at 40° C. for 12h, cooled, and poured into ice water. The yellow solid which formed was filtered off, washed with water, and dried to give 1,4-dihydro-6-chloro-7-ethyl-5-nitroquinoxalin-2,3-dione and 1,4-dihydro-7-chloro-6-ethyl-5-nitroquinoxalin-2,3-dione (2.55 g, 91%), as a mixture (1.7:1 ratio).
Wird geladen…