Highly Efficient Synthesis of O-(2,4-Dinitrophenyl)hydroxylamine. Application to the Synthesis of Substituted N-Benzoyliminopyridinium Ylides

An efficient two-step synthesis of O-(2,4-dinitrophenyl)hydroxylamine is described along with a comparison of its aminating efficiency with O-mesitylenesulfonylhydroxylamine (MSH). It was used in an expedient N-amination/benzoylation procedure involving various substituted pyridines, leading to polysubstituted N-benzoyliminopyridinium ylides, and the scope of its amination power was studied.