Nickel Complexes of Allyl and Vinyldiphenylphosphine

Monodentate phosphine-ligatednickel compounds, e.g., [Ni(PPh3)(4)] are relevant as active catalystsacross a broad range of reactions. This report expands upon the coordinationchemistry of this family, offering the reactivity of allyl- and vinyl-substituteddiphenylphosphine (PPh2R) with [Ni(COD)(2)] (COD= 1,5-cyclooctadiene). These reactions provide three-coordinate dinickelacyclesthat are intermolecularly tethered through adjacent {Ni}-olefin interactions.The ring conformation of such cycles has been studied in the solid-stateand using theoretical calculations. Here, a difference in reactionoutcome is linked to the presence of an allyl vs vinyl group, wherethe former is observed to undergo rearrangement, bringing about challengesin clean product isolation.

Automated summary

This report explores the coordination chemistry of monodentate phosphine-ligated nickel compounds and investigates the reactivity of allyl- and vinyl-substituted diphenylphosphine with [Ni(COD)(2)]. The reactions lead to intermolecularly tethered three-coordinate dinickelacycles through adjacent {Ni}-olefin interactions. The ring conformation of these cycles has been studied experimentally and theoretically. The presence of an allyl vs vinyl group is found to affect the reaction outcome, causing challenges in obtaining pure products.