NO Disproportionation by {RhNO}9 Pincer-Type Complexes

CARINA GAVIGLIO; JUAN PELLEGRINO; DAVID MILSTEIN; FABIO DOCTOROVICH

Iguazú

Congreso; 6to Simposio Latinoamericano de Química de Coordinación y Organometálica; 2017

Nitrosyl complexes are denoted as {MNO}n, according to the Enemark-Feltham notation.1 In a recent paper the one-electron reduction of the four-coordinate {RhNO}8 complex [Rh(PCPtBu)(NO)][BF4] (1+) was reported (PCPtBu =1,3-bis[(di-tert-butylphosphino)methyl]-4,6-dimethylphenyl).2 The new {RhNO}9 species 1? was well characterized in solution and its reactivity towards halide organic substrates was studied, resulting in C-X bond activation. Herein the reactivity of 1? towards NO? is presented, where the five-coordinate complex Rh(PCPtBu)(NO)(NO2) (2) was obtained as the final product while N2O was evolved. A mechanism is proposed which is supported experimentally and by DFT calculations. Complex 2 was independently prepared by reaction of [Rh(PCPtBu)(NO)][BF4] (1+) with sodium nitrite and was fully characterized including X-ray diffraction structure analysis.Also new {RhNO}8/9 complexes with a PNPtBu ligand were prepared (PNPtBu = 2,6-bis-(di-tert-butylphosphinomethyl)pyridine) and structure and reactivity studies are presented.