Nickel-Catalyzed Secondary Benzylic C-O Bond Borylation

A remote steric hindrance ligand (m-Bu- t)(2)C6H3PCy2 (L1) was synthesized to promote Ni-catalyzed C-O bond activation. The reaction achieved high yields for secondary benzylic C(sp(3))-O borylation in non-pi-extended systems under mild conditions. Mechanistic studies indicate that the nickel complex containing 1 equiv of L1 serves as the active catalyst, while increased loading of L1 gives the inactive bisligated Ni species. Acetanilide is crucial for the cross-coupling reaction, which facilitates generation of the monoligated nickel species.