Iridium-Catalyzed Twofold C–H/C–H Activation and Annulation: Access to Anti-Kasha Emission and Photosensitive-Phosphorescent Materials

The first example of a multifunctional anti-Kasha emission-photosensitive-phosphorescent material has been synthesized via an efficient twofold C-H/C-H activation and annulation protocol. Both experimental data and theoretical calculations have validated the anti-Kasha emission property of phenothiazinium and phenoxazinium salts. Specifically, the anti-Kasha emission property of phenoxazinium salts enables dual-channel emission intensity ratio imaging for visualizing cellular and intercellular structures, while also endowing them with the capability to specifically target mitochondria in living cells. Furthermore, these newly developed photosensitive-phosphorescent materials have been demonstrated to act as efficient photocatalysts in C-H bond functionalization reactions. In addition, the novel phenothiazinium salts demonstrate photosensitive and phosphorescent properties in PVA (poly(vinyl alcohol)) films: upon light irradiation, they undergo a significant blue shift accompanied by ultralong room-temperature phosphorescence, making them highly promising for applications in encryption and multichannel information storage.