The Suzuki coupling reaction is one of the most practiced classes of catalytic C-C bond formation. The development of new means of activating molecules and bonds over old catalysts for C-C bond formation is a fundamental objective for chemists. Here, we report the room-temperature C-C bond formation over heterogeneous Pd catalysts by light-mediated catalyst activation. We employ stimulated electron transfer at the metal-semiconductor interface from optically active mesoporous carbon nitride nanorods to Pd nanoparticles. This photocatalytic pathway is highly efficient for coupling aryl halides with various coupling partners with high activity and selectivity under photo irradiation and very mild conditions.

A heptazine‐based polymer network (HMP‐3) with a donor–acceptor (D–A) structure was prepared and tested as catalyst for photocatalytic hydrogen evolution from water. Compared to other heptazine‐based materials, which are typically prepared at high temperatures and have recently received much interest as metal‐free photocatalysts, the low‐temperature protocol applied here allows the defined introduction of organic functional groups within the polymer backbone. The structure of HMP‐3 contains alternating heptazine and benzothiadiazole moieties as electron acceptors connected by aminobenzene bridges as electron donors. The resulting material leads to enhanced hydrogen evolution compared to graphitic carbon nitride materials prepared at high temperatures (>500 °C) most probably because of the stabilization of photogenerated charge carriers in the D–A structure.

In this communication we describe the oxidative CC bond formation of tertiary amines with various nucleophiles under very mild and environmental friendly conditions by using mesoporous graphitic carbon nitride (mpg‐C3N4) semiconductor as a heterogeneous, metal‐free photosensitizer in combination with visible light and oxygen as the terminal oxidation agent. This system can be further combined with proline‐organocatalysis to achieve oxidative tandem photocatalysis, demonstrating a rich cascade of chemical possibilities of the current photosynthesis system.

Heterogeneous catalysis for trifluoromethylations and perfluoroalkylations has been performed. Through the usage of cheap, metal-free and recyclable mesoporous graphitic carbon nitride (mpg-CN) it was possible to fluoroalkylate various arenes by the reductive activation of sulfonyl chlorides with visible light. Thus, we were able to demonstrate the robustness and versatility of mpg-CN as a photoredox catalyst beyond water splitting and the activation of oxygen.

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