A Photosensitive Cationic Macrocycle Based on Triphenylamine as Photocatalysts for Selective Photooxidation of Phosphines, Styrenes, and Hydroazobenzenes

Despite the fact that water provides significant benefits in decreased environmental pollution, low safety risks, and small costs of production, the application of water as a solvent in chemical reactions remains an ongoing challenge due to its lack of organophilicity and high polarity, hindering its efficiency and widespread application in organic synthesis. In this study, we have designed and synthesized a triphenylamine modified macrocyclic molecule, TPPB, which encompasses superior water solubility and outstanding efficiency and selectivity in generating singlet oxygen (O-1(2)) under blue light irradiation in water. Furthermore, TPPB exhibits excellent efficiency in facilitating the photooxidation of phosphines, styrenes, and also hydroazobenzenes in water with remarkable stability and versatility. This study presents an approach for creating macrocyclic photosensitizers, expanding the use of macrocyclic molecules in the realm of photocatalytic organic processes.