Chloroacetaldehyde → 6-Fluoroimidazo[1,2-a]pyridine

Participants

Reaction Steps

To a solution of 2-amino-5-fluoropyridine (10 g) in ethanol (200 mL), a solution of chloroacetaldehyde 50% in water (56 mL, 4.0 equiv.) was added. The reaction mixture was heated at reflux 2 Hrs, then was concentrated under reduced pressure to 100 mL. The residue was diluted in AcOEt (100 mL) and washed with a saturated aqueous solution of NaHCO3 (2*150 mL). The combined aqueous were saturated with NaHCO3 and extracted back with AcOEt (2*100 mL). The combined organic layers were washed with brine (100 mL), dried over Na2SO4 and concentrated under reduced pressure.

Provenance & Evidence