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Dioxygen activation by an osmium-dihydride: preparation and characterization of a d4 square-planar complex
Miguel A Esteruelas1, Francisco J Modrego, Enrique Oñate
1Departamento de Química Inorgánica-Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-Consejo Superior de Investigaciones Científicas, 50009-Zaragoza, Spain. maester@posta.unizar.es
Abstract:
Exposure of OsH2Cl2(PiPr3)2 to air or bubbling with pure O2 affords the dioxo-Os(VI) compound OsO2Cl2(PiPr3)2 as result of a direct O=O double bond activation reaction. This Os(VI) species is reduced in the presence of n-BuLi to the novel dioxo-Os(IV) derivative OsO2(PiPr3)2, a rare example of a d4 square-planar compound.
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