Lithium hydroxide, monohydrate → [2-(4-Chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-cyclohexyl-acetic acid

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Reaction Steps

To the solution of 0.17 g (0.469 mmol) [2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-cyclohexyl-acetic acid ethyl ester (Example 1, intermediate b) in 4 ml dioxan and 2 ml water, 34 mg (1.42 mmol) lithium hydroxide monohydrate were added and the reaction was stirred at reflux temperature for 2 h. After cooling to room temperature the solution was partially evaporated, diluted with 2 ml water and the pH was adjusted to 1-2 with 1M aqueous hydrochloric acid. The resulting suspension was stirred for 30 min. and then filtered. The filter cake was thoroughly washed with water and dried under high vacuum. Colorless solid (83%). MS (Turbo Spray): m/z=333.3 [M−H].

Provenance & Evidence