Photocyclizing Molecular Rotors in Angewandte

We have published an article titled ‘Extended Conjugation Attenuates the Quenching of Aggregation-Induced Emitters by Photocyclization Pathways‘. Click this link to read the paper in Angewandte Chemie.

Congratulations to former PhD student Andrew Turley who is the lead author alongside other team members from the McGonigal Group and our collaborators at Durham.

Abstract: Herein, we expose how the antagonistic relationship between solid-state luminescence and photocyclization of oligoaryl alkenes chromophores is modulated by the conjugation length of their alkenyl backbones. Heptaaryl cycloheptatriene molecular rotors exhibit aggregation-induced emission characteristics. We show that their emission is turned off upon breaking the conjugation of the cycloheptatriene by epoxide formation. While this modification is deleterious to photoluminescence, it enables formation of extended polycyclic frameworks by Mallory reactions. We exploit this dichotomy (i) to manipulate emission properties in a controlled manner and (ii) as a synthetic tool to link together pairs of phenyl rings in a specific sequence. This method to alter the tendency of oligoaryl alkenes to undergo photocyclization can inform the design of solid-state emitters that avoid this quenching mechanism, while also allowing selective cyclization in syntheses of polycyclic aromatic hydrocarbons.