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Transient Formation and Reactivity of a High-Valent Nickel(IV) Oxido Complex.

ABSTRACT: A reactive high-valent dinuclear nickel(IV) oxido bridged complex is reported that can be formed at room temperature by reaction of [(L)₂Ni(II)₂(?-X)₃]X (X = Cl or Br) with NaOCl in methanol or acetonitrile (where L = 1,4,7-trimethyl-1,4,7-triazacyclononane). The unusual Ni(IV) oxido species is stabilized within a dinuclear tris-?-oxido-bridged structure as [(L)₂Ni(IV)₂(?-O)₃]²⁺. Its structure and its reactivity with organic substrates are demonstrated through a combination of UV-vis absorption, resonance Raman, ¹H NMR, EPR, and X-ray absorption (near-edge) spectroscopy, ESI mass spectrometry, and DFT methods. The identification of a Ni(IV)-O species opens opportunities to control the reactivity of NaOCl for selective oxidations.

SUBMITTER: Padamati SK

PROVIDER: S-EPMC5492195 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Transient Formation and Reactivity of a High-Valent Nickel(IV) Oxido Complex.

Padamati Sandeep K SK Angelone Davide D Draksharapu Apparao A Primi Gloria G Martin David J DJ Tromp Moniek M Swart Marcel M Browne Wesley R WR

Journal of the American Chemical Society 20170620 25

A reactive high-valent dinuclear nickel(IV) oxido bridged complex is reported that can be formed at room temperature by reaction of [(L)2Ni(II)2(μ-X)3]X (X = Cl or Br) with NaOCl in methanol or acetonitrile (where L = 1,4,7-trimethyl-1,4,7-triazacyclononane). The unusual Ni(IV) oxido species is stabilized within a dinuclear tris-μ-oxido-bridged structure as [(L)2Ni(IV)2(μ-O)3]2+. Its structure and its reactivity with or ...[more]

PMID: 28581745

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