ethyl 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylate

Synthesis

General procedure for the synthesis of ethyl 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylate from ethyl 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylate: 18.4 g (0.05 mol) of ethyl 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylate 1-tert-butyl ester 2-ethyl ester was dissolved in 165 mL of dichloromethane and cooled to 0°C. 38.0 mL of trifluoroacetic acid was added slowly over 5 minutes. The cooling bath was removed and the reaction mixture was stirred at room temperature for 2 hours. Subsequently, the reaction mixture was poured into 500 mL of saturated aqueous sodium bicarbonate solution. The aqueous phase was extracted three times with 150 mL of dichloromethane and the organic phase was combined. The organic phase was washed with 200 mL of brine, dried over anhydrous magnesium sulfate and filtered. The solvent was evaporated and the residue was dried under high vacuum to give 12.0 g (95.5%) of the target product, ethyl 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylate, as a colorless solid.ISP-MS: m/e = 269.2 ([M+H]+).

References

[1] Patent: WO2005/849, 2005, A1. Location in patent: Page/Page column 62
[2] Patent: US2003/207888, 2003, A1