Redirecting of Charge Transfer Enables the Control of the Photoactivity of Terarylenes

Photoinduced charge transfer affects the efficiency and selectivity of photochemical reactions. Incorporation of donating groups into the isoquinolinium core allowed us to overcome the photochemical inactivity of the corresponding dithienyl-substituted terarylenes, presumably by redirecting the charge transfer within the molecule, and gave access to a new family of thermally reversible photoswitches.