Ammonium Chloride → Ethyl 5-bromo-1H-pyrrolo[2,3-c]pyridine-2-carboxylate

Participants

Reaction Steps

Route A: To a solution of 3-(2-bromo-5-nitropyridin-4-yl)-2-oxopropionic acid ethyl ester (Preparation 25, 3.38 g, 10.7 mmol) in THF (50 mL) and ethanol (100 mL) was added saturated ammonium chloride solution (50 mL) and iron powder (3.57 g, 64.0 mmol) and the reaction heated under reflux for 2 h. The reaction mixture was filtered through celite and washed several times with ethyl acetate. The solvent was removed in vacuo and the remainder partitioned between saturated sodium hydrogen carbonate solution (100 mL) and ethyl acetate (3×150 mL). The combined organic fractions were dried (MgSO4) and concentrated in vacuo to give the title compound as a brown solid. δH (CD3OD): 1.42 (3H, t), 4.43 (2H, q), 7.14 (1H, s), 7.85 (1H, s), 8.58 (1H, s); m/z (ES+)=269 [M+H]+.

Provenance & Evidence