Ammonium Chloride → (-)-2-[2-(4-Chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-acetamide

Participants

Reaction Steps

To a turbid solution of 1 g (2.47 mMol) (−)-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-cyclohexyl-acetic acid in 15 ml N,N-dimethyl formamide were added 0.264 g (4.94 mmol) ammonium chloride, 0.42 ml (2.47 mmol) ethyl diisopropylamine, 0.378 g (2.47 mmol) N-hydroxybenzotriazole monohydrate and 0.947 g (4.94 mmol) N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride. The reaction mixture is stirred for 14 h at room temperature and then poured onto water. The phases were separated and the aqueous phase extracted three times with ethyl acetate. The combined organic layers were twice washed with water, once with brine, dried over magnesium sulfate, filtered and evaporated. The residue was purified by silica gel column chromatography using a MPLC system (CombiFlash Companion, Isco Inc.) eluting with ethyl acetate. Colorless solid (93%). MS (Turbo Spray): m/z=404.3 [M+H].

Provenance & Evidence