Sulfuric Acid → 5-Trifluoromethyl-1H-pyrrolo[2,3-b]pyridine 2-ethyl carboxylate

Participants

Reaction Steps

Put 0.3 g (1.3 mmol) of 5-trifluoromethyl-1H-pyrrolo[2,3-b]pyridine-2-carboxylic acid (Angew Chem Int Ed 2004, 43(34), 4526-4528) and 50 mL of ethanol in a 100-mL flask equipped with a magnetic stirrer. Add, to this solution, 0.5 mL of concentrated sulfuric acid. The reaction mixture is then refluxed for 18 hours. The cooled solution is concentrated to dryness at reduced pressure. The residue is taken up in dichloromethane (100 mL), the organic phase is washed successively with a normal aqueous solution of sodium hydroxide (30 mL), with water (20 mL) and then with a saturated aqueous solution of sodium chloride. It is dried over sodium sulfate and then concentrated at reduced pressure. 0.29 g (1.12 mmol) of the expected product is isolated in the form of a yellow powder.

Provenance & Evidence