Copper-Catalyzed Direct Alkylation of Perfluoroarenes with Hydrocarbons

Abstract

Construction of carbon–carbon bonds is one of the most essential tools in chemical synthesis. In the previously established cross-coupling reactions, pre-functionalized starting materials are employed usually in the form of arylor alkyl (pseudo)halides or their metallated derivatives. However, direct use of arenes and alkanes via a twofold oxidative C–H bond activation strategy to access chemoselective C(sp2 )‒C(sp3 ) cross-couplings is highly challenging due to the low reactivity of carbon–hydrogen (C–H) bonds and the difficulty in suppressing side reactions such as homocouplings. Herein, we present a copper-catalyzed cross-dehydrogenative coupling of perfluoroarenes with alkanes. Mechanistic information was obtained by combining experimental and computational studies to suggest that the optimal diketimine copper catalyst system plays a dual role to activate both sp3 and sp2 C‒H bonds.

Photocatalytic C−H Functionalization of Nitrogen Heterocycles Mediated by a Redox Active Protecting Group

“…This redox active protecting group strategy has already some precedents in photocatalysis, but so far the cleavage of the C−X bond required either strongly reducing photocatalysts [11] or transition metals, [12] thus restricting the scope of transformations available for the resulting α‐amino radical. Herein, we report a complementary approach relying on halogen‐atom transfers (XAT) [13] mediated by a readily available organic photocatalyst and enabling the introduction of alkyl and aryl substituents [14] …”