Synthesis of 6-Bromoindanone: Trifluoromethanesulfonic acid (0.35 mL, 4 mmol) was added to a solution of the amide substrate 3-(4-Bromophenyl)-N-(4-nitrophenyl)propanamide (6) (1 mmol) in anhydrous CHCl₃ or CH₂Cl₂ (2 mL). The mixture was stirred for 4 h and then poured into ice. The product was extracted with CHCl₃, and the organic layer was washed with H₂O and brine, then dried over anhydrous sodium sulfate. The crude product was isolated and purified by column chromatography (hexane:ethyl acetate).
Recovery of nitro-substituted aniline: The aqueous layer was made basic by the addition of 10 M NaOH, and the solution was extracted with CHCl₃. The organic layer was washed with H₂O and brine (2×), then dried over anhydrous sodium sulfate to yield 6-bromoindanone in 88% yield
[1].
