Palladium-Catalyzed ipso-Borylation of Aryl Halides Promoted by Lewis Acid-Mediated Electrophilic Activation of Aryl(halo)palladium(II) Complex.

ABSTRACT

Palladium-catalyzed ipso-borylation of aryl halides, well-known as Miyaura borylation, is one of the reliable synthetic methods for organoborons. This reaction involves base-mediated nucleophilic activation of diboron that enables transmetalation of an aryl(halo)palladium(II) intermediate with a diboron. As an alternative, herein, we have established Lewis acid-mediated conditions for borylating (pseudo)haloarenes that require no external base. The electrophilic activation of the aryl(halo)palladium(II) intermediate via dehalogenation with Lewis acidic zinc complexes promotes the borylation.