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Dioxygen Splitting by a Tantalum(V) Complex Ligated by a Rigid, Redox Non-Innocent Pincer Ligand
Jack Underhill1, Eric S Yang1, Till Schmidt-Räntsch2
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Rd., Oxford, OX1 3TA, United Kingdom.
Abstract:
The reaction of TaMe3 Cl2 with the rigid acridane-derived trisamine H3 NNN yields the tantalum(V) complex [TaCl2 (NNNcat )]. Subsequent reaction with dioxygen results in the full four-electron reduction of O2 yielding the oxido-bridged bimetallic complex [{TaCl2 (NNNsq )}2 O]. This dinuclear complex features an open-shell ground state due to partial ligand oxidation and was comprehensively characterized by single crystal X-ray diffraction, LIFDI mass spectrometry, NMR, EPR, IR and UV/VIS/NIR spectroscopy. The mechanism of O2 activation was investigated by DFT calculations revealing initial binding of O2 to the tantalum(V) center followed by complete O2 scission to produce a terminal oxido-complex.
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