Rapid and General Amination of Aryl Boronic Acids and Esters Using -(Diphenylphosphinyl)hydroxylamine (DPPH).

-(Diphenylphosphinyl)hydroxylamine (DPPH) is a general reagent for the conversion of (hetero)aryl boronic acids and esters to primary anilines. The transformation proceeds rapidly at rt and exhibits a broad substrate scope and exceptional functional-group tolerance. In terms of rate, the reaction is relatively insensitive to the electronic properties of the substrate, in contrast to similar reactions using electrophilic amination reagents such as hydroxylamine--sulfonic acid. Consequently, this protocol is particularly useful for accessing electron-deficient (hetero)aryl anilines, which had been challenging to prepare using prior methods.