Nickel-catalysed hydrogen exchange of aniline, phenol, and their alkylated derivatives with deuterium oxide

Abstract

Selective exchange of hydrogen atoms ortho to amino or hydroxyl groups, together with benzylic hydrogen atoms in aniline, phenol, and their C- alkylated derivatives, was achieved by allowing these compounds to react with deuterium oxide over nickel on kieselguhr at 99°. In addition to the benzylic hydrogen atoms, alkyl hydrogen atoms farther from the aromatic ring underwent slower exchange. Hydrogen atoms ortho to methoxyl did not exchange. Mechanisms of the catalytic exchange reactions are discussed in the light of the results of deuterium distribution measurements and poisoning experiments with electron donors.