Dimethylformamide → 4-fluoro-1-methyl-1H-indole-3-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

Under stirring at 0° C., phosphoryl chloride (2.07 ml, 22.1 mmol) was added dropwise to DMF (30 ml). After completion of the dropwise addition, a solution of 4-fluoro-1-methylindole (2.20 g, 14.7 mmol) in DMF (15 ml) was added dropwise and the reaction mixture was stirred at room temperature for 4 hours. The reaction mixture was poured in 1N NaOH (120 ml), followed by extraction with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous sodium sulfate, and distilled under reduced pressure to remove the solvent. The residue was purified by chromatography on a silica gel column, whereby from n-hexane-ethyl acetate (1:1, v/v) eluate fractions, 4-fluoro-1-methylindole-3-carbaldehyde (1.43 g, 55%) was obtained as a red solid.

Provenance & Evidence