Fast and efficient synthesis of 14C labelled benzonitriles and their corresponding acids

C-14-Anthranilic acid has been prepared in a fast and efficient way in a two-step reaction in 82% overall radiochemical yield. Thus, 2-iodoaniline was transformed into 2-amino-[7- C-14]-benzonitrile using a palladium catalyzed cyanation with zinc C-14-cyanide. Subsequent basic hydrolysis of the cyano group afforded [7- C-14]-anthranilic acid. The method was successfully applied to a benzophenone scaffold, 4-iodophenol and 4-iodobenzoic acid producing the corresponding carboxylic acids in good to excellent radiochemical yields (62-82%) and with high specific activity (1.94-1.98GBq/mmol).