In recent years, the catalytic activity of scandium triflate Sc(OTf)3 has attracted significant attention due to its robust Lewis acidity and the oxophilicity of Sc3+. These features have led to impressive progress in developing diverse organic reactions, including C-C bond formation. The Sc3+ also facilitates single electron transfer in photoinduced reactions either by coordination to an organophotoredox catalyst, which modifies its redox reactivity, or by the formation of a scandium-superoxide anion complex after electron transfer from a light-absorbing redox-active compound. The prior consideration of Sc3+ as a redox-inactive/innocent metal ion initially hampered the investigation of the possibility of using Sc(OTf)3 as a sole visible light photoredox catalyst. This work demonstrates the use of Sc(OTf)3 as a visible light photocatalyst capable of direct and mild aerobic oxidative C-H functionalisation of aromatic substrates by oxidation of the benzylic position and direct cyanation of the aromatic ring.

Central Laboratories University of Chemistry and Technology Prague Prague 166 286 Czech Republic

Chemistry Department Faculty of Science Assiut University Assiut 71515 Egypt

Department of Inorganic Chemistry University of Chemistry and Technology Prague Prague 166 28 Czech Republic

Department of Molecular Electrochemistry and Catalysis J Heyrovský Institute of Physical Chemistry AS CR v v i 182 23 Prague 8 Czech Republic

Department of Organic Chemistry University of Chemistry and Technology Prague Prague 166 28 Czech Republic

Department of Physics School of Natural Sciences University of Hull Cottingham Road Hull HU6 7RX United Kingdom

Institute of Physical Chemistry and Chemical Physics Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava Bratislava 81237 Slovak Republic

Ultrafast Laser Spectroscopy Lab Center for Integrative Petroleum Research KFUPM Dhahran 31261 Saudi Arabia

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