Hydrochloric Acid → 1-((1R,2R)-2-Methyl-cyclohexyl)-2-thiophen-2-ylmethyl-1H-benzoimidazole-5-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To 8.32 g 4-((1R,2R)-2-Methyl-cyclohexylamino)-3-(2-thiophen-2-yl-acetylamino)-benzoic acid methyl ester were added 40 ml of 4M hydrochloric acid in dioxane and the mixture was heated in four portions in a microwave reactor to 130° C. for 20 min. 2 ml of water were added to each vial and the reactions were heated to 130° C. for 40 min. The reactions were then combined and concentrated and the pH was adjusted to 6 by addition of saturated aqueous sodium bicarbonate. The resulting mixture was extracted with ethyl acetate twice. The combined organic layers were dried over sodium sulphate and concentrated. The product precipitated upon treatment with diisopropylether and 5.65 g (76%) of 1-((1R,2R)-2-Methyl-cyclohexyl)-2-thiophen-2-ylmethyl-1H-benzoimidazole-5-carboxylic acid were obtained.

Provenance & Evidence