Citric Acid → Benzyl 1H-pyrrolo[2,3-b]pyridin-5-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

1H-pyrrolo[2,3-b]pyridin-5-amine (9.45 g, 71.05 mmol) was dissolved in THF (150 mL) and stirred at 0° C. under an atmosphere of nitrogen. Benzyl chloroformate (20.3 mL, 142.10 mmol, 2.0 Eq) was added dropwise over a period of 15 minutes and the mixture allowed to stir at room temperature for 30 minutes. The mixture was treated with 4M NaOH (aq) (53.3 mL, 213.16 mmol, 3.0 Eq) over a period of 15 minutes and the resultant brown solution left to stir for 16 hours. The reaction mixture was taken to pH 4 (125 mL of 10% aq. citric acid) and the 2 layers were separated. The aqueous layer was back extracted with EtOAc and the combined organics were dried over magnesium sulphate, filtered and dried under vacuum. The crude product was purified by column chromatography (50% EtOAc/Petroleum Ether) to give 14.59 g (77%) of pale yellow solid.

Provenance & Evidence