Palladium-Catalyzed Chemoselective Borylation of (Poly)halogenated Aryl Triflates and Their Application in Consecutive Reactions

This study reports the palladium-catalyzed chemoselective borylation of (poly)halogenated aryl triflates with a reactivity order of C-Cl>C-OTf. A catalyst system comprising Pd(OAc)(2) and SelectPhos (L1) enables a reaction with high reactivity and chemoselectivity. The consecutively chemoselective borylation reaction followed by the chemoselective intermolecular Suzuki-Miyaura reaction can be performed using a one-pot two-step approach to synthesize unsymmetrical biaryl compounds containing the triflate moiety. The reaction can be scaled up to the gram scale without diminishing the yield and chemoselectivity.