Reductive disproportionation of nitric oxide mediated by low-valent uranium

Abstract

The reductive disproportionation of nitric oxide (1 atm) is mediated by the bulky U^III aryloxide [U^III(OAr^Ad,Ad,Me)₃] (^Ad,Ad,MeArO = O-C₆H₂-2,6-Ad-4-Me) (1) to form the U^V terminal oxo species [(^Ad,Ad,MeArO)₃U^V(O)] (2) and N₂O, as confirmed by single crystal X-ray diffraction and GC-MS measurements. The reaction is quantitative in the solid state. Mechanistic and theoretical studies of the reaction suggest that the N–N bond is formed by the coupling of an η¹-O bound nitric oxide ligand with gaseous NO to give an η¹-(N₂O₂)¹⁻ intermediate prior to the spontaneous extrusion of N₂O to yield the U^V terminal oxo species 2.