A Practical Synthesis of 2-{4-[4-Fluoro-3-(trifluoromethyl)phenyl]-2-(piperidin-4-yl)-1H-imidazol-1-yl}-N,N-dimethylethanamine

Abstract

A practical synthesis of the title compound was accomplished by hydrogenation of 2-{4-[4-fluoro-3-(trifluoromethyl)phenyl]-2-(pyridin-4-yl)-1H-imidazol-1-yl}-N,N-dimethylethanamine. The latter was obtained by N-alkylation of 4-{4-[4-fluoro-3-(trifluoromethyl)phenyl]-1H-imidazol-2-yl}pyridine. Treatment of N-{2-[4-fluoro-3-(trifluoromethyl)phenyl]-2-oxoethyl}isonicotinamide hydrochloride with ammonium acetate in acetic acid provided 4-{4-[4-fluoro-3-(trifluoromethyl)phenyl]-1H-imidazol-2-yl}pyridine. Coupling of 2-amino-1-[4-fluoro-3-(trifluoromethyl)phenyl]ethanone 4-methylbenzene sulfonate with pyridine 4-carboxylic acid using either T₃P or EDCI-HOBt provided N-{2-[4-fluoro-3-(trifluo­romethyl)phenyl]-2-oxoethyl}isonicotinamide hydrochloride.

Key words

imidazole - EDCI - T₃P - ammonium acetate - hydrogenation

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