Dimethylformamide → 3-Formyl-1H-indole-5-carbonitrile

Participants

Reaction Steps

Phosphoryl chloride (4.24 ml, 45.48 mmol) was added dropwise to dimethylformamide (3.52 ml, 45.48 mmol) and stirred for 30 mins at room temperature. A solution of 1H-indole-5-carbonitrile (5.39 g, 37.9 mmol) in dimethylformamide (10 ml) was added dropwise. A solid precipitated, further dimethylformamide (10 ml) was added to aid stirring and the reaction mixture was then stirred at room temperature for 3 hr. Water was added to quench the reaction mixture which was then stirred for 18 hr. The stirring was stopped and the reaction mixture was left to stand, after 24 hr a pink solid had precipitated in the organic layer. The layers were separated and organic layer filtered, washed with water and dried to give the desired product (5.44 g, 84%). 1H NMR (DMSO) δ 7.60-7.80 (m, 2H), 8.20-8.30 (m, 2H), 10.00 (s, 1H), 12.20-12.35 (s, br, 1H).

Provenance & Evidence