Phosphinite-Ni(0) Mediated Formation of a Phosphide-Ni(II)-OCOOMe Species via Uncommon Metal–Ligand Cooperation

Reversible transformations are observed between a phosphide-nickel­(II) alkoxide and a phosphinite-nickel(0) species via a P–O bond formation coupled with a 2-e– redox change at the nickel center. In the forward reaction, the nickel(0) dinitrogen species (PPOMeP)­Ni­(N2) (2) and {(PPOMeP)­Ni}2(μ-N2) (3) were formed from the reaction of (PPP)­NiCl (1) with a methoxy anion. In the backward reaction, a (PPP)­Ni­(II) moiety was regenerated from the CO2 reaction of 3 with the concomitant formation of a methyl carbonate ligand in (PPP)­Ni­(OCOOMe) (7). Thus, unanticipated metal–ligand cooperation involving a phosphide based ligand is reported.