Oxidative Addition of a Phosphinite P−O Bond at Nickel

Oxidative addition is an essential elementary reaction in organometallic chemistry and catalysis. While a diverse array of oxidative addition reactions has been reported to date, examples of P−O bond activation are surprisingly rare. Herein, we report the ligand-templated oxidative addition of a phosphinite P−O bond in the diphosphinito aniline compound HN(2-OPⁱPr₂-3,5-^tBu-C₆H₂)₂ [H(P₂ONO)] at Ni⁰ to form (PONO)Ni(HPⁱPr₂) after proton rearrangement. Notably, the P−O cleavage occurs selectively over an amine N−H bond activation. Additionally, the ligand cannibalization is reversible, as addition of XPR₂ (X = Cl, Br; R = ⁱPr, Cy) to (PONO)Ni(HPⁱPr₂) readily produces either symmetric or unsymmetric (P₂ONO)NiX species and free HPⁱPr₂. Finally, the mechanisms of both the initial P−O bond cleavage and its subsequent reconstruction are investigated to provide further insight into how to target P−O bond activation.