Pyrazino-1,3a,6a-triazapentalenes as organic photocatalysts for aerobic sulfoxidation.

Pyrazino-triazapentalenes (PyTAPs) are introduced as a new class of organic photocatalysts for visible-light-driven aerobic sulfoxidation. Their modular architecture enables the tuning of their photophysical and electronic properties, providing opportunities to tailor their photocatalytic reactivity for selective thioether oxidation under mild conditions. Mechanistic investigations support oxygen sensitisation and reactive oxygen species formation during the photocatalytic process.