Cupferron is jargon for the ammonium salt of the conjugate base derived from N-nitroso-N-phenylhydroxylamine. Its formula is NH4[C6H5N(O)NO]. The anion, abbreviated CU−, is a NONOate. It once was a common qualitative inorganic analysis reagent, binding metal ions into brightly colored complexes. The metals bond through the two oxygen atoms, forming five-membered chelate rings.
Synthesis and complexes
Cupferron is prepared from phenylhydroxylamine and an NO+ source: C6H5NHOH + C4H9ONO + NH3 → NH4[C6H5N(O)NO] + C4H9OH
Being a bidentate mono-anionic ligand, CU− forms complexes analogous to those produced with acetylacetonate. Illustrative complexes include Cu(CU)2, Fe(CU)3, and Zr(CU)4.
See also Nitroso N-nitroso Hydroxamate Phenylhydroxylamine
References