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A heterobimetallic superoxide complex formed through O2 activation between chromium(II) and a lithium cation
Fabian Schax1, Simon Suhr, Eckhard Bill
1Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Strasse 2, 12489 Berlin (Germany) http://www.chemie.hu-berlin.de/aglimberg.
Abstract:
The reaction of 1,1,3,3-tetraphenyl-1,3-disiloxandiol (LH2) with n-butyllithium and CrCl2 results in a mononuclear chromium(II) complex (1) that further reacts with O2 at low temperatures to yield a mononuclear chromium(III) superoxide complex [L2CrO2(THF)][Li2(THF)3] (2). The crystal structure revealed that the chromium superoxido entity is stabilized by the coordination to an adjacent lithium cation. Complex 2 thus contains an unprecedented heterobimetallic [Cr(III)(μ-O2)Li(+)] core; beyond this it is the first chromium superoxide for which a temperature-dependent magnetic characterization could be achieved, and the first structurally characterized representative with chromium in an exclusive O-donor environment.
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