Formic Acid → 6-Bromo-4H-imidazo[4,5-b]pyridine

Participants

Reaction Steps

A solution of 5-bromo-pyridine-2,3-diamine (3.0 g, 15.96 mmol) and HCOOH (1.1 mL) in triethoxymethane (48 mL) was stirred at 90° C. for 3 h. The reaction mixture was concentrated under reduced pressure. The residue was purified by silica gel chromatography eluting with 40:1 DCM/MeOH to give 6-bromo-3H-imidazo[4,5-b]pyridine as a light brown solid (2.74 g, 86.7%). 1H NMR (300 MHz, DMSO-d6) δ 8.49 (s, 1H), 8.44 (s, 1H), 8.30 (br s, 1H). LCMS (ESI) m/z 198 (M+H)+.

Provenance & Evidence