Phosphoric Anhydride in Organic Synthesis. Migration of the Dihydroxyphosphoryl Group in Amides

Acyclic and cyclic amides are phosphorylated by phosphoric anhydride. The phosphorylated acyclic amides exhibit a pronounced tendency to N-O reversible or irreversible phosporotropy. In cyclic amides it is less specific. For hydrazide of benzoic acid there is determined 1 – 4 reversible phosphorotropy.