A combined experimental and theoretical study on the reactivity of nitrenes and nitrene radical anions

Nitrene transfer reactions represent one of the key reactions to rapidly construct new carbon-nitrogen bonds and typically require transition metal catalysts to control the reactivity of the pivotal nitrene intermediate. Herein, we report on the application of iminoiodinanes in amination reactions under visible light photochemical conditions. While a triplet nitrene can be accessed under catalyst-free conditions, the use of a suitable photosensitizer allows the access of a nitrene radical anion. Computational and mechanistic studies rationalize the access and reactivity of triplet nitrene and nitrene radical anion and allow the direct comparison of both amination reagents. We conclude with applications of both reagents in organic synthesis and showcase their reactivity in the reaction with olefins, which underline their markedly distinct reactivity. Both reagents can be accessed under mild reaction conditions at room temperature without the necessity to exclude moisture or air, which renders these metal-free, photochemical amination reactions highly practical. Gaining in-depth understanding of photochemical processes is key for developing more sustainable and efficient chemical transformations. Here the authors show that under visible light photochemical conditions, iminoiodinanes undergo formation of triplet nitrenes or nitrene radical anions, depending on the use of a photosensitizer; These reagents are studied in amination reactions with olefins.