Herein, we report a general and scalable continuous flow metallaphotoredox amidine arylation protocol that efficiently couples diverse (hetero)aryl halides and amidines under mild open-air conditions. Mechanistic studies revealed the pivotal role of an in situ generated triazine cocatalyst, which acts as the quencher in the photocatalytic cycle via an underexplored oxidative quenching pathway. Its strategic use as a cocatalyst enabled faster kinetics, broader nucleophile scope, including sulfonamides and amines, and the use of alternative solvents. These insights unlock a previously challenging reactivity, enhancing both the synthetic utility and sustainability of our nickel/photoredox cross-coupling.
Gasparetto, M., Sveiczer, A., Fermi, A., Raji, M., Fair, R.J., Noël, T., et al. (2025). In Situ Generated Triazine Co-Catalyst Unlocks Amidine Arylation under Dual Nickel/Photoredox Catalysis: A Platform for Mild C–N Bond Formation. ACS CATALYSIS, 15, 21213-21223 [10.1021/acscatal.5c07508].
In Situ Generated Triazine Co-Catalyst Unlocks Amidine Arylation under Dual Nickel/Photoredox Catalysis: A Platform for Mild C–N Bond Formation
Gasparetto, Matteo;Fermi, Andrea;Ceroni, Paola
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2025
Abstract
Herein, we report a general and scalable continuous flow metallaphotoredox amidine arylation protocol that efficiently couples diverse (hetero)aryl halides and amidines under mild open-air conditions. Mechanistic studies revealed the pivotal role of an in situ generated triazine cocatalyst, which acts as the quencher in the photocatalytic cycle via an underexplored oxidative quenching pathway. Its strategic use as a cocatalyst enabled faster kinetics, broader nucleophile scope, including sulfonamides and amines, and the use of alternative solvents. These insights unlock a previously challenging reactivity, enhancing both the synthetic utility and sustainability of our nickel/photoredox cross-coupling.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
