Dimethylformamide → 5-(tert-Butyl)-1H-indole-3-carbonitrile

Participants

Reaction Steps

Chlorosulfonyl isocyanate (1 ml) was added dropwise to a suspension of 5-tert-butylindole (2.1 g) in acetonitrile (15 ml) over 10 minutes under ice-cooling. After being stirred for 1 hour at same temperature, a solution of N,N-dimethylformamide (1 ml) in acetonitrile (20 ml) was added to the mixture and then the mixture was stirred at 50° C. for 1 hour. The reaction mixture was poured into ice-water and extracted with ethyl acetate. The extract was washed with brine, dried over magnesium sulfate and evaporated under reduced pressure. The resulting residue was subjected to column chromatography on silica gel and eluted with a mixture of ethyl acetate and n-hexane. The fractions containing the objective compound were combined and concentrated under reduced pressure to give 5-tert-butyl-3-cyanoindole (1.20 g).

Provenance & Evidence