Cupferron


Cupferron is jargon for the ammonium salt of the conjugate base derived from N-nitroso-N-phenylhydroxylamine. It once was a common reagent for the complexation of metal ions, being of interest in the area of qualitative inorganic analysis. Its formula is
NH4. The anion binds to metal cations through the two oxygen atoms, forming five-membered chelate rings.

Synthesis and complexes

Cupferron is prepared from phenylhydroxylamine and an NO+ source:
Being a bidentate mono-anionic ligand, CU− forms complexes analogous to those produced with acetylacetonate. Illustrative complexes include Cu2, Fe3, and Zr4.