Ruthenium-Catalyzed C-H Bond Functionalizations of 1,2,3-Triazol-4-yl-Substituted Arenes: Dehydrogenative Couplings Versus Direct Arylations

Abstract

The chemoselectivity of ruthenium-catalyzed C-H bond arylations on triazol-4-yl-substituted arenes was found to depend on the substitution pattern of both substrates. While various aryl chlorides led to products stemming from direct arylations, ortho-substituted aryl halides in combination with ortho-alkylated arenes preferentially resulted in oxidative homo-couplings.

arylations - C-H activation - dehydrogenation - ruthenium - triazoles

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The use of other sacrificial oxidants, such as Cu(OAc)₂, Ag₂O, benzoquinone, [t-BuO]₂, or allyl acetate, did not meet with success, under otherwise identical reaction conditions.