Hydrochloric Acid → 2-methyl-4-(trifluoromethyl)-1H-indole

Participants

Reaction Steps

0.271 ml of 5N sodium hydroxide is added to a solution of 460 mg of 1-benzenesulfonyl-2-methyl-4-trifluoromethyl-1H-indole in 1.4 ml of ethanol and 0.44 ml of dimethoxyethane. The reaction mixture is maintained at reflux for 6 hours and poured into water acidified with a hydrochloric acid solution until pH=1 and extracted with ethyl acetate. The organic phases are combined and washed with a 10% sodium bicarbonate solution and a saturated sodium chloride solution, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The residue is purified by silica column chromatography, elution being carried out with a mixture of heptane and diisopropyl ether (98/2, then 95/5: v/v), so as to give 214 mg of 2-methyl-4-trifluoromethyl-1H-indole, in the form of a pale yellow oil, which is used in the next step.

Provenance & Evidence