Diarylethene Isomerization by Using Triplet-Triplet Annihilation Photon Upconversion

Green-to-blue triplet-triplet annihilation photon upconversion with the well-studied upconversion pair 9,10-diphenylanthracene (DPA)/platinum octaethylporphyrin (PtOEP) was used to reversibly drive the photoisomerization of diarylethene (DAE) photoswitches by using visible light. By carefully selecting the kinetic and spectral properties of the molecular system as well as the experimental geometry, a single green light source can be used to selectively trigger both the ring-opening and the ring-closing reactions, whilst also inducing fluorescence from the colored closed isomer that can be used as a readout to monitor the isomerization process in situ. The upconversion solution and the DAE solution are kept physically separated, allowing them to be characterized both concomitantly and individually without further separation processes. The ring-closing reaction using upconverted photons was quantified and compared to the efficiency of direct isomerization with ultraviolet light.

Automated summary

Green-to-blue triplet-triplet annihilation photon upconversion is used to drive reversible photoisomerization of diarylethene (DAE) photoswitches using visible light. By carefully selecting the molecular system and experimental geometry, a single green light source can selectively trigger ring-opening and ring-closing reactions. The upconversion solution and DAE solution can be characterized concomitantly and individually without further separation processes. The efficiency of ring-closing reaction using upconverted photons is compared to direct isomerization with ultraviolet light.