Nitric Acid → (+/-)-5'-Amino-6'-nitro-3-methyl-spiro[imidazolidine-4,2'-indane]-2,5-dione
Reaction equation
[CH3:1][N:2]1[C:6]2([CH2:14][C:13]3[C:8](=[CH:9][CH:10]=[C:11]([N+:15]([O-:17])=[O:16])[CH:12]=3)[CH2:7]2)[C:5](=[O:18])[NH:4][C:3]1=[O:19].[N+:20]([O-])(O)=O.OS(O)(=O)=O>>[NH2:20][C:10]1[CH:9]=[C:8]2[C:13](=[CH:12][C:11]=1[N+:15]([O-:17])=[O:16])[CH2:14][C:6]1([C:5](=[O:18])[NH:4][C:3](=[O:19])[N:2]1[CH3:1])[CH2:7]2Participants
4
Procedure
To (±)-5′-amino-3-methyl-spiro[imidazolidine-4,2′-indane]-2,5-dione (100 mg, 0.432 mmol, described in Intermediate 7) at 0° C. were added 70% HNO3 (1 mL) followed by conc. H2SO4 (1 mL). The resulting mixture was allowed to warn to ambient temperature and stirred for 18 h, then poured onto ice and the precipitate was removed by filtration. The aqueous filtrate was purified by HPLC using a reversed phase C18 column and eluting with a gradient of H2O:CH3CN:CF3CO2H—90:10:0.1 to 5:95:0.1. Lyophilization provided the title compound. MS: m/z=277 (M+1).