Dimethylformamide → 6-fluoro-5-methoxy-1H-indole-3-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

POCl3 (10.9 ml, 71 mmol) is added dropwise to 21 ml of dimethylformamide under N2 at 10-20° C., is stirred 15 minutes, then a 13 ml dimethylformamide solution of 5-methoxy-6-fluoro-indole (J. Med. Chem., 22:63-69, 1979; 10.7 g, 64.7 mmol) is added at a rate to keep the reaction temperature between 10 and 20° C. After the addition is complete, the mixture is stirred for 1 hour. Crushed ice and aqeuous NaOH (12.5 g/50 ml H2O) is added to reaction. The resulting mixture is heated to reflux with a heat gun for 1 minute, cooled to 10° C., and is filtered to give 11.8 g of 6-fluoro-5-methoxy-1H-indole-3-carbaldehyde (95%).

Provenance & Evidence