Accessing Ni(0) to Ni(IV) nickel-carbon-phosphorus bond reorganization.

Two-electron oxidation of a NiPh(PCP) pincer complex initiates phosphine ligand insertion, generating an η-arylphosphonium moiety coordinated to Ni. The reaction is fully reversible under reducing conditions. X-ray crystallography, NMR/EPR spectroscopy, electrochemistry, and DFT calculations support the proposed Ni-C-P bond reorganization mechanisms, which access oxidation states from Ni to Ni.