Triethylamine → N-{1-[9-Chloro-1-(2,4,6-trichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]propyl}-2,2-difluoroacetamide

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Reaction Steps

A mixture of crude 1-[9-chloro-1-(2,4,6-trichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]propan-1-amine (100 mg), difluoroacetic acid (0.0186 mL, 0.296 mmol), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (75.5 mg, 0.394 mmol), 1-hydroxybenzotriazole (53.2 mg, 0.394 mmol) and triethylamine (0.0824 mL, 0.591 mmol) in N,N-dimethylformamide (2 mL) was stirred at room temperature for 3 h, and diluted with ethyl acetate. The resultant mixture was washed with water and brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with a 0-30% ethyl acetate/n-hexane gradient mixture and NH silica gel eluting with a 30% ethyl acetate/n-hexane mixture to give the title compound as a colorless solid (42.4 mg, 0.0812 mmol).

Provenance & Evidence