Ammonium Acetate → 4-Fluoro-2-methyl-5-phthalimidoindole

Participants

Reaction Steps

2-(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%).

Provenance & Evidence