Dual nickel/photocatalytic C–N couplings are performed with an organic heterogeneous photocatalyst, in an oscillatory plug flow reactor. Reaction was complete in 20 min residence time, enabling 2.7 g h−1 throughput and 10-fold catalyst recycling.

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Over the last decades, organic chemistry has taken a resolute step towards green catalytic synthesis. This tries to ensure efficient and sustainable base chemical production, while also safeguarding human health and environment. To this end, the development of novel, non-toxic and effective catalytic systems, capable of driving value-added chemical transformations in environmentally benign solvents (e. g. water) is highly desirable. Moreover, these new catalysts need to be metal-free, easy to prepare and potentially recyclable. Carbon dots, that are relatively new carbon-based nanoparticles, fulfil all these requirements owing to their outstanding physico-chemical features, thus emerging as promising nano-catalytic platforms. This Perspective highlights the recent advances in carbon dots synthesis and their applications in organic catalysis and photocatalysis, with particular attention to green non-metal-doped systems. Finally, forward-looking opportunities within this field are mentioned here.

Two-dimensional (2D) nanostructures are a frontier in materials chemistry as a result of their extraordinary properties. Metal-free 2D nanomaterials possess extra appeal due to their improved cost-effectiveness and lower toxicity with respect to many inorganic structures. The outstanding electronic characteristics of some metal-free 2D semiconductors have projected them into the world of organic synthesis, where they can function as high-performance photocatalysts to drive the sustainable synthesis of high-value organic molecules. Recent reports on this topic have inspired a stream of research and opened up a theme that we believe will become one of the most dominant trends in the forthcoming years.

Phenols (I) are extremely relevant chemical functionalities in natural, synthetic and industrial chemistry. Their corresponding electron‐rich anions, namely phenolates (I), are characterized by interesting physicochemical properties that can be drastically altered upon light excitation. Specifically, phenolates (I) become strong reducing agents in the excited state and are able to generate reactive radicals from suitable precursors via single‐electron transfer processes. Thus, these species can photochemically trigger strategic bond‐forming reactions, including their direct aromatic C−H functionalization. Moreover, substituted phenolate anions can act as photocatalysts to enable synthetically useful organic transformations. An alternative mechanistic manifold is represented by the ability of phenolate derivatives I to form ground state electron donor‐acceptor (EDA) complexes with electron‐poor radical sources. These complementary scenarios have paved the way for the development of a wide range of relevant organic reactions. In this Minireview, we present the main examples of this research field, and give insight on emerging trends in phenols photocatalysis towards richer organic synthesis.

Two efficient continuous flow iodo­perfluoro­alkylation methods are described: using 0.05 mol % perylene diimide (PDI) photocatalyst under 450 nm irradiation or substoichiometric triethylamine under 405 nm irradiation. These methods enable dramatically elevated productivity versus batch processes. The triethylamine-mediated method is explored mechanistically and in substrate scope. The gram-scale synthesis of an active pharmaceutical ingredient side chain is also reported in flow, via a photochemical iodoperfluoroalkylation followed by hydrogenolysis.

We describe a novel efficient photochemical procedure for the direct iodoperfluoroalkylation of terminal olefins. The process uses a simple and inexpensive perylenediimide (PDI) in an extremely low catalytic loading and occurs with visible light irradiation. The reported methodology is highly viable from a synthetic point of view, since it proceeds under mild reaction conditions with a significant rate of production. Preliminary mechanistic investigations are also reported.

The use of amine‐rich N‐doped carbon nanodots (NCNDs) for the photochemical radical perfluoroalkylation of organic compounds is reported. This operationally simple approach occurs under mild conditions producing valuable new C−C bonds. The chemistry is driven by the ability of NCNDs to directly reach an electronically excited state upon light absorption, thereby successively triggering the formation of reactive radical species from simple perfluoroalkyl iodides. Preliminary mechanistic studies are also reported.