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DOE OSTI · 2471039

Multielectron Bond Cleavage Processes Enabled by Redox-Responsive Phosphinimide Ligands

Winslow, Charles C.·Rathke, Paul·Rittle, Jonathan
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Abstract

The activation of small molecules via multielectron redox processes offers promise in mediating difficult transformations related to energy conversion processes. While molecular systems that engage in one- and two-electron redox processes are widespread, those that participate in the direct transfer of four or more electrons to small molecules are very rare. To that end, we report a mononuclear Cr II complex competent for the 4-electron reduction of dioxygen (O 2 ) and nitrosoarenes. These systems additionally engage in facile two-electron group transfer reactivity, including O atom excision and nitrene transfer. Structural, spectroscopic, and computational studies support bond activation processes that intimately occur at a mononuclear chromium(phosphinimide) center and highlight the unusual structural responsiveness of the phosphinimides in stabilizing a range of metal redox states.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAromatic compoundsChemistryHydrocarbonsLigandsMetalsRedox reactions

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Winslow, Charles C., Rathke, Paul, Rittle, Jonathan. 2023-10-17. Multielectron Bond Cleavage Processes Enabled by Redox-Responsive Phosphinimide Ligands. https://doi.org/10.1021/acs.inorgchem.3c02307

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