[C:1]([CH2:4][C:5]1[C:10]([F:11])=[C:9]([N:12]2[C:16](=[O:17])[C:15]3=[CH:18][CH:19]=[CH:20][CH:21]=[C:14]3[C:13]2=[O:22])[CH:8]=[CH:7][C:6]=1[N+:23]([O-])=O)(=O)[CH3:2].C([O-])(=O)C.[NH4+]>CC(C)=O.[Cl-].[Cl-].[Cl-].[Ti+3]>[F:11][C:10]1[C:9]([N:12]2[C:16](=[O:17])[C:15]3=[CH:18][CH:19]=[CH:20][CH:21]=[C:14]3[C:13]2=[O:22])=[CH:8][CH:7]=[C:6]2[C:5]=1[CH:4]=[C:1]([CH3:2])[NH:23]22-(Acetylmethyl)-3-fluoro-4-phthalimidonitrobenzene (4.7 g, 14 mmol) was dissolved in acetone (80 ml). Ammonium acetate (210 ml of a freshly prepared 4M aqueous solution) was added followed by titanium trichloride (140 ml, 140 mmol, 15% aqueous solution). The mixture was stirred vigorously for 30 minutes then extracted with ethyl acetate. The organic phase was washed with a hydrogen carbonate solution, brine, dried (MgSO4), filtered and the solvent evaporated off. The residue was purified by flash chromatography using 0.5% methanol in methylene chloride. Evaporation of the solvent gave 4-fluoro-2-methyl-5-phthalimidoindole (1.27 g; 31%).
Wird geladen…