NO Disproportionation by {RhNO}9 Pincer-Type Complexes

JUAN PELLEGRINO; CARINA GAVIGLIO; DAVID MILSTEIN; FABIO DOCTOROVICH

Iguazú

Simposio; SILQCOM6; 2017

NO Disproportionation by {RhNO}9 Pincer-Type ComplexesCarina Gaviglio,1 Juan Pellegrino,1 David Milstein2 and Fabio Doctorovich11DQIAQF/INQUIMAE - CONICET, FCEN, UBA, Ciudad Universitaria, Pabellón II, 3rdfloor, Bs. As., Argentina.cgaviglio@qi.fcen.uba.ar2 Department of Organic Chemistry and # Department of Chemical Research Support, Weizmann Institute of Science, Rehovot , IsraelNitrosyl 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.1. Enemark, J. H.; Feltham, R. D. Coord. Chem. Rev. 1974, 13, 339.2. Pellegrino, J. et al. Organometallics 2013, 32, 6555.