Gold-Catalyzed Oxidative C-H Arylation with Organoboron Reagents
Direct C(sp2)-H functionalization/arylation has attracted increasing interest since the substrates do not need to be functionalized in contrast to classical cross-coupling reactions.1 Despite significant progress,2 multiple challenges including low reactivity, lack of selectivity in the activation of an specific C(sp2)-H bonds and formation of homocoupling products (Ar1Ar1, Ar2Ar2) are still difficult to master.3 Herein, we report an efficient synthesis of biaryl compounds through a gold-catalyzed oxidative cross-coupling of arenes with strong electron-deprived aryl boronates. Non-symmetric biaryls can be synthesized with high levels of regio- and chemoselectivity under additives and directing groups-free conditions.4 This methodology shows orthogonal reactivity and complementary scope with respect to already existing methods.5
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