When two different acyl radicals are introduced into o-aminophenol the positions taken by these groups are determined by a number of fa. ct0rs. l If the acyls are R-~ O and R!-C= C),~ the heaviest and most acidic radical is usually found attached to nitrogen, regardless of the order of introd~ ction.~ To meet this requiremerit the migration of acyl from nitrogen to oxygen must occur in one of these reactions. When the acyls are R-&= CJ and R--QC= O ...