An unprecedented method that makes use of the cooperative interplay between molecular iodine and photoredox catalysis has been developed for dual light‐activated intramolecular benzylic C−H amination. Iodine serves as the catalyst for the formation of a new C−N bond by activating a remote Csp3 −H bond (1,5‐HAT process) under visible‐light irradiation while the organic photoredox catalyst TPT effects the reoxidation of the molecular iodine catalyst. To explain the compatibility of the two involved photochemical steps, the key N−I bond activation was elucidated by computational methods. The new cooperative catalysis has important implications for the combination of non‐metallic main‐group catalysis with photocatalysis.

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Mechanochemical conditions have been applied to an iridium(III)-catalyzed C-H bond amidation process for the first time. In the absence of solvent, the mechanochemical activation enables the formation of an iridium species that catalyzes the ortho-selective amidation of benzamides with sulfonyl azides as the nitrogen source. As the reaction proceeds in the absence of organic solvents without external heating and yields the desired products in excellent yields within short reaction times, this method constitutes a powerful, fast, and environmentally benign alternative to the common solvent-based standard approaches.

In a proof-of-principle study, a planetary ball mill was applied to rhodium(III)-catalyzed C-H bond functionalization. Under solventless conditions and in the presence of a minute amount of Cu(OAc)2, the mechanochemical activation led to the formation of an active rhodium species, thus enabling an oxidative Heck-type cross-coupling reaction with dioxygen as the terminal oxidant. The absence of an organic solvent, the avoidance of a high reaction temperature, the possibility of minimizing the amount of the metallic mediator, and the simplicity of the protocol result in a powerful and environmentally benign alternative to the common solution-based standard protocol.

A direct metal-free amination of arylalkynes has been developed, which proceeds by reaction of the terminal alkyne with the hypervalent iodine reagent PhI(OAc)NTs(2) within a single-step operation. This unprecedented intermolecular C-H to C-N bond conversion provides rapid access to the important class of ynamides. In addition to the title reaction, the related transformation between alkylated alkynes and the iodine(III) reagent is also discussed.

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The potential of homogeneous oxidation catalysis employing bromine has remained largely unexplored. We herein show that the combination of a tetraalkylammonium bromide and meta-chloroperbenzoic acid offers a unique catalyst system for the convenient and selective oxidation of saturated C(sp )-H bonds upon photochemical initiation with day light. This approach enables remote, intramolecular, position-selective C-H amination as demonstrated for 20 different examples. For the first time, an N-halogenated intermediate was isolated as the active catalyst state in a catalytic Hofmann-Löffler reaction. In addition, an expeditious one-pot synthesis of N-sulfonyl oxaziridines from N-sulfonamides was developed and exemplified for 15 transformations. These pioneering examples provide a change in paradigm for molecular catalysis with bromine.

Visible light initiates the stereoselective formation of two new bonds, a C À C and a C À Si bond, during the addition of acylsilanes to alkynes. At room temperature this photochemically induced transformation can be applied for the preparation of chromone derivatives in a highly atom-economic manner.