Hydrochloric Acid → 8-Amino-6-(2,4-dichloro-phenyl)-imidazo[1,2-a]pyridine-7-carbonitrile

Participants

Reaction Steps

A mixture of crude 8-azido-6-(2,4-dichloro-phenyl)-imidazo[1,2-a]pyridine-7-carbonitrile (68 mg, 0.21 mmol) and triphenylphosphine (83.7 mg, 0.32 mmol) in MeOH (2.5 mL) was stirred and refluxed for 1 h. 2 M HCl in water (1 mL) was added and the reaction mixture was further refluxed for 1 h. The reaction mixture was cooled to RT, concentrated under vacuum and the remaining residue was dissolved in water. The aqueous solution was basified to pH 12 by the addition of 2 M NaOH in water. The resulting slurry was extracted with DCM (2×) and the combined organic fractions were dried over Na2SO4, filtered and evaporated. The remaining residue was dissolved in hot MeOH, then the solution was slowly cooled to RT and the formed precipitate was filtered and washed with cold MeOH to yield the title compound (32.5 mg, 0.11 mmol, 52%) as a brownish solid. MS: 303 [M+1]+; HPLC: AtRet=1.72.

Provenance & Evidence