Dimethylformamide → 5-methoxy-1-methyl-1H-indole-3-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

While cooling in order to maintain the temperature of the reaction medium below 15° C., phosphorus oxychloride (9 ml) is added dropwise to 35 ml of dimethylformamide (DMF), and 5-methoxy-1-methylindole (14.1 g), dissolved in DMF (25 ml) is added in a single portion. The resulting heterogeneous mixture is heated to 110° C. for 1 minute, and then maintained at 65° C. for 30 minutes while being stirred mechanically. After the mixture has been allowed to cool, it is decomposed by adding 200 ml of ice-cold water, and then treated with 5N sodium hydroxide solution (100 ml). The precipitate formed is filtered off and recrystallized in ethanol, to give 14.53 g (87.7%) of colorless scales, m.p.=134° C.

Provenance & Evidence