El Diario de Pontevedra : periódico liberal: Ano XXVII Número 7742 - 1910 marzo 1

Copper­(II) aryl species are proposed key intermediates in Cu-catalyzed cross-coupling reactions. Novel three-coordinate copper­(II) aryls [Cu^II]-C₆F₅ supported by ancillary β-diketiminate ligands form in reactions between copper­(II) alkoxides [Cu^II]-O^<i>t</i>Bu and B­(C₆F₅)₃. Crystallographic, spectroscopic, and DFT studies reveal geometric and electronic structures of these Cu­(II) organometallic complexes. Reaction of [Cu^II]-C₆F₅ with the free radical NO_(g) results in C-N bond formation to give [Cu]­(η²-ONC₆F₅). Remarkably, addition of the phenolate anion PhO^– to [Cu^II]-C₆F₅ directly affords diaryl ether PhO-C₆F₅ with concomitant generation of the copper­(I) species [Cu^I]­(solvent) and {[Cu^I]-C₆F₅}⁻. Experimental and computational analysis supports redox disproportionation between [Cu^II]-C₆F₅ and {[Cu^II]­(C₆F₅)­(OPh)}⁻ to give {[Cu^I]-C₆F₅}⁻ and [Cu^III]­(C₆F₅)­(OPh) unstable toward reductive elimination to [Cu^I]­(solvent) and PhO-C₆F₅

A Copper(II) Thiolate from Reductive Cleavage of an <i>S</i>‑Nitrosothiol

<i>S</i>-Nitrosothiols RSNO represent circulating reservoirs of nitric oxide activity in the plasma and play intricate roles in protein function control in health and disease. While nitric oxide has been shown to reductively nitrosylate copper­(II) centers to form copper­(I) complexes and ENO species (E = R₂N, RO), well-characterized examples of the reverse reaction are rare. Employing the copper­(I) β-diketiminate [Me₂NN]­Cu, we illustrate a clear example in which an RS–NO bond is cleaved to release NO_gas with formation of a discrete copper­(II) thiolate. The addition of Ph₃CSNO to [Me₂NN]Cu generates the three-coordinate copper­(II) thiolate [Me₂NN]­CuSCPh₃, which is unstable toward free NO

A Copper(II) Thiolate from Reductive Cleavage of an <i>S</i>‑Nitrosothiol

<i>S</i>-Nitrosothiols RSNO represent circulating reservoirs of nitric oxide activity in the plasma and play intricate roles in protein function control in health and disease. While nitric oxide has been shown to reductively nitrosylate copper­(II) centers to form copper­(I) complexes and ENO species (E = R₂N, RO), well-characterized examples of the reverse reaction are rare. Employing the copper­(I) β-diketiminate [Me₂NN]­Cu, we illustrate a clear example in which an RS–NO bond is cleaved to release NO_gas with formation of a discrete copper­(II) thiolate. The addition of Ph₃CSNO to [Me₂NN]Cu generates the three-coordinate copper­(II) thiolate [Me₂NN]­CuSCPh₃, which is unstable toward free NO