1,1'-Carbonyldiimidazole → 6-(N-cyclopentylmethylcarbamoyl)indole

Participants

Reaction Steps

A solution of indole-6-carboxylic acid (9.41 g) and 1,1'carbonyldiimidazole (10.6 g) in methylene chloride (290 ml) was heated at reflux, under nitrogen, for 30 minutes. The solution was cooled and treated with cyclopentylmethylamine (7.0 g). This mixture was heated to reflux for 30 minutes. The resultant solution was then diluted with methylene chloride, washed successively with 10% (v/v) hydrochloric acid, 20% (w/v) aqueous sodium hydroxide, and brine, dried (MgSO4), and evaporated to give 6-(N-cyclopentylmethylcarbamoyl)indole (14.4 g, 91%) as an ivory powder, mp 148°-150°; NMR (80 MHz, DMSO-d6): 3.19(dd, 2H, CH2NH), 6.46(br d, 1H, H3 -indole), 7.91(d, 1H, H7 -indole), 8.29(t, 1H, CH2NH).

Provenance & Evidence