Carbon Dioxide → 1,4-dimethyl-1H-indole-2-carboxylic acid

Participants

Reaction Steps

A solution of 1,4-dimethyl-1H-indole (0.9 g, 6.2 mmole) in anhydrous Et2O (20 mL) was treated with 2.5 M n-BuLi in hexanes (5.0 mL, 12 mmole) and the reaction was heated at reflux for 15 hr. The dark reaction mixture was poured into a slurry of excess crushed dry ice in Et2O, and the mixture was allowed to stand for 1 hr. Water (10 mL) was added, the layers separated, and the aqueous layer was filtered through Celite®. The clear filtrate was acidified with 2.0 N HCl to pH 2, and the precipitate was collected and dried to afford the title compound (0.29 g, 26.4%) as an off-white solid: MS (ES) m/e 190.2 (M+H)+.

Provenance & Evidence