Pyridine → 1-[8-Chloro-1-(2,4-dichloro-6-methylphenyl)-2,3-dihydro-1H-imidazo[1,2-a]benzimidazol-5-yl]propyl acetate

Participants

Reaction Steps

To a solution of 1-[8-chloro-1-(2,4-dichloro-6-methylphenyl)-2,3-dihydro-1H-imidazo[1,2-a]benzimidazol-5-yl]propan-1-ol (150 mg, 0.365 mmol) and pyridine (0.15 mL, 1.85 mmol) in tetrahydrofuran (10 mL) was added acetic anhydride (0.113 mL, 1.20 mmol) at room temperature. The mixture was stirred at room temperature for 5 hr. Then the mixture was warmed to 45° C. and stirred at 45° C. for 16 hr. Acetic anhydride (0.113 mL, 1.2 mmol) and pyridine (0.30 mL, 3.71 mmol) were added to the reaction mixture at room temperature. The mixture was stirred at 45° C. for 20 hr. The reaction mixture was concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 20-50% ethyl acetate/n-hexane gradient mixture and recrystallization from 2-propanol/n-hexane to give the title compound (116.5 mg, 0.257 mmol, 60%) as colorless crystals.

Provenance & Evidence