N-Fluorobenzenesulfonimide → 5-fluoro-2-(4-isopropyl-phenyl)-7-methoxy-1-(2-methoxy-ethyl)-1H-benzoimidazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 400 mg (0.98 mmol) 5-bromo-2-(4-isopropyl-phenyl)-7-methoxy-1-(2-methoxy-ethyl)-1H-benzoimidazole in 3 ml dry THF, n-BuLi (0.740 ml, 1.18 mmol) is added slowly at −78° C. After stirring for 45 min. at −78° C. N-fluoro-bis(phenylsulfonyl)amine (568.7 mg, 1.77 mmol) is added. Stirring at −78° C. is continued for another hour and then the reaction mixture is warmed to room temperature. After that the reaction mixture is poured on water and extracted (3×) with ethyl acetate. The combined organic layers are washed with water (3×) and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue is purified by flash-chromatography on silica gel (hexane:EtOAc=2:1−>1:1) to afford 40 mg of the title compound as a colorless oil.

Provenance & Evidence