Hydroxyamine hydrochloride → 3-[3-(Pyridin-3-yl)phenyl]imidazo[1,2-alpha]pyridine-7-carboxaldehyde oxime

Participants

Reaction Conditions

Reaction Steps

3-[3-(Pyridin-3-yl)phenyl]imidazo[1,2-α]pyridine-7-carboxaldehyde (0.30 g, 1.0 mmol) and hydroxylamine hydrochloride (0.208 g, 3.0 mmol) were suspended in ethanol (15 ml) then heated at 60° C. for 45 min. The mixture was diluted with 50% methanol in dichloromethane (200 ml) and pre-adsorbed onto silica. Purification by flash column chromatography on silica gel eluting with dichloromethane/methanol/conc. ammonia (95:5:0.5) gave the title compound (297 mg, 94%) as a white foam. Further purification of this material by preparative thin-layer chromatography eluting with dichloromethane/methanol/conc. ammonia (95:5:0.5) gave (E)-3-[3-(pyridin-3-yl)phenyl]imidazo[1,2-α]pyridine-7-carboxaldehyde oxime as a white solid followed by (Z)-3-[3-(pyridin-3-yl)phenyl]imidazo[1,2-α]pyridine-7-carboxaldehyde oxime also as a white solid.

Provenance & Evidence