Tetrahydrofuran → [9-Chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl](dicyclopropyl)methanol

Participants

Reaction Conditions

Reaction Steps

Cyclopropylmagnesium bromide (1.0 M solution in tetrahydrofuran, 4.8 mL, 4.8 mmol) was added to a stirred solution of methyl 9-chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole-6-carboxylate (400 mg, 0.974 mmol) in tetrahydrofuran (5.0 mL), and the mixture was stirred at 60° C. for 3 hr. The reaction was quenched by aqueous saturated ammonium chloride, and the mixture was extracted with ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture. The filtrate was concentrated in vacuo to give the solid, which was recrystallized from ethyl acetate/diisopropyl ether to give the title compound as a colorless crystal (320 mg, 0.691 mmol, 71%).

Provenance & Evidence