Organic photocatalyst generate solvated electrons via two consecutive photoinduced processes

Organic photocatalysts offer a solution to drive chemical transformations that are endergonic in the dark. The consecutive photoinduced electron transfer mechanism (ConPET), based on isophthalonitrile chromophores (4CzIPN or 4DPAIPN), proposes a mechanism in which the photocatalyst (PC) is reduced to a radical anion, PC•-, followed by the absorption of a second photon that generates a highly reducing species, *PC•-. We report the investigation of the radical anions 4CzIPN•- and 4DPAIPN•-, which do not behave as super-reducing agents: they are short-lived (ca. 20 ps), non-emissive, and are not quenched by common organic substrates. Instead, the photogeneration of solvated electrons is observed through a consecutive two-photon induced mechanism (ConPies). These photogenerated solvated electrons are responsible for the exceptional reducing power of these photocatalytic systems.2