Conjugated porous polymer based on BOPHY dyes as photocatalyst under visible light

The design and synthesis of new conjugated porous polymers based on BOPHY moiety (IEP-7 and IEP-8) which shows heterogeneous photocatalytic activity under visible light is reported. Both porous polymers are efficient photocatalysts in the selective oxidation of several sulfides into sulfoxides. The proposed mechanism is elucidated by steady state photolysis, fluorescence quenching and transient absorption spectroscopy, which follows a type I photosensitizing oxidation involving superoxide radical anion formation (O-2(-)). Electron transfer from the sulfide derivative to the photocatalyst singlet exited state takes place, giving rise the corresponding radical ion pairs. Back electron transfer from oxygen molecular to the reduced BOPHY moiety with recovery of the photocatalyst, led to the formation of superoxide radical anion in an exergonic process.