872619-43-7

67-56-1

849068-61-7

872619-43-7

5-Bromo-1H-pyrrolo[2,3-b]pyridine-3-carboxylic acid (480 mg, 2 mmol, 1.0 eq.) was used as a starting material and mixed with concentrated hydrochloric acid. A methanol solution containing sulfuric acid (0.5 mL, catalytic amount) was added to the mixture and the reaction mixture was subsequently refluxed for 24 hours. Upon completion of the reaction, the solvent was removed by concentration via rotary evaporator. The obtained residue was dissolved in ethyl acetate and subsequently washed with saturated aqueous sodium bicarbonate solution. The organic phase was dried with anhydrous sodium sulfate, filtered and concentrated to give methyl 5-bromo-1H-pyrrolo[2,3-b]pyridine-3-carboxylate (450 mg, 85% yield) as a white solid.LCMS analysis showed (M+H)+ m/z calculated value of 256.1 and measured value of 256.1.