A Convenient Procedure for the Palladium‐Catalyzed Cyanation of Aryl Halides

A useful source of cyanide for the palladium-catalyzed cyanation of aryl halides is acetone cyanohydrin (see scheme; dpppe=1,5-bis(diphenylphosphanyl)pentane, tmeda=N,N,N′,N′-tetramethylethylenediamine). The key to the success of the reaction is the slow dosage of the cyanation reagent to the reaction mixture to prevent the deactivation of the palladium catalyst caused by excess cyanide ions in solution.