Ethylparaben → 4-{2-[2-(4-Chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-ethoxy}-benzoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To the solution of 0.3 g (0.77 mmol) 2-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-ethanol (Ex. 1, int. c) in 3 mL tetrahydrofuran, 0.13 g (0.84 mmol) ethyl 4-hydroxybenzoate and 0.22 g (084 mmol) triphenylphosphine were added. The solution was cooled to 0° C., 0.15 g (0.84 mmol) diethyl azodicarboxylate dissolved in 2 mL tetrahydrofuran were added dropwise and the reaction stirred at room temperature for 18 h. The reaction was adsorbed on silica gel and purified by silica gel column chromatography using a MPLC system (CombiFlash Companion, Isco Inc.) eluting with a gradient of n-heptane:ethyl acetate (100:0 to 100:40 v/v) to yield the title compound as a white foam (55%). MS (Turbo Spray): m/z=539.2 [M+H].

Provenance & Evidence