Method for the production of telmisartan (4'-[2-N-propyl-4-methyl-6-(1-methylbenzimidazol-2-yl)benzimidazol-1-ylmethyl]biphenyl-2-carboxylic acid)

摘要

Disclosed is a process for preparing telmisartan, wherein (a) 2-N-propyl-4-methyl-6-(1'-methylbenzimidazol-2'-yl)-benzimidazole of formula (I) is reacted with a compound of general formula (IV), wherein Z denotes a leaving group, and the resulting compound is worked up, if desired, (b) the cyano group of the compound 2-cyano-4'-[2"-N-propyl-4"-methyl-6"-(1"'-methylbenzimidazol-2'"-yl)benzimidazol-1"-ylmethyl]biphenyl of formula (V) thus obtained is then converted by hydrolysis in water, in an organic solvent or in a mixture of an organic solvent with water in the presence of a base at temperatures between 80 and 200 deg C into the acid function.