Nonclassical Arylative Meyer–Schuster Rearrangement through Ni-Catalyzed Inner-Sphere Acyloxy Migration

A Ni­(II)-catalyzed unconventional Meyer–Schuster rearrangement (MSR) is paired with cross-coupling through inner-sphere acyloxy migration. Various propargyl acetates react with aryl boronic acids, leading to the formation of a range of α-arylated enone derivatives. This transformation is enabled by the use of a P∧N-type phosphinooxazoline (PHOX) ligand, which allows the substrate to coordinate with the square planar Ni­(II) center. It initiates arylnickelation of the alkyne moiety followed by intramolecular transposition of the acetate group. This nonclassical approach allows for the addition of electron-rich nucleophiles at the α-position without the need for redox additives. A series of controlled experiments including 18O isotope labeling studies and computational analysis corroborated the inner-sphere acyloxy migration.