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Updated: Aug 3, 2025

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Reactivity of a Strictly T-Shaped Phosphine Ligated by an Acridane Derived NNN Pincer Ligand
Aaron J King1, Josh Abbenseth1,2, Jose M Goicoechea3
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
Abstract:
The steric tuning of a tridentate acridane-derived NNN pincer ligand allows for the isolation of a strictly T-shaped phosphine that exhibits ambiphilic reactivity. Well-defined phosphorus-centered reactivity towards nucleophiles and electrophiles is reported, contrasting with prior reports on this class of compounds. Reactions towards oxidants are also described. The latter result in the two-electron oxidation of the phosphorus atom from +III to +V and are accompanied by a strong geometric distortion of the NNN pincer ligand. By contrast, cooperative activation of E-H (HCl, HBcat, HOMe) bonds proceeds with retention of the phosphorus redox state. When using H2 O as a substrate, the reaction results in the full disassembly of H2 O to its constituent atoms, highlighting the potential of this platform for small molecule activation reactions.
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