Title
Photoresponsiveness of Anthracene-Based Supramolecular Polymers Regulated via a σ-Platinated 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene Photosensitizer
Author
Yifei Han, Mingyang Liu, Ruolei Zhong, Zongchun Gao, Ze Chen, Mingming Zhang, Feng Wang
Year
2019
Journal
Inorganic Chemistry
Abstract
Anthracene and its derivatives have attracted tremendous interest in recent years because of their intriguing photoresponsive behaviors. Our research group has previously constructed anthracene-based supramolecular polymers, which display multicycle anthracene–endoperoxide photoswitching in a macroscopic manner. However, high-energy light excitation (λ = 365–460 nm) is required for anthracene-to-endoperoxide photooxygenation, giving rise to severe photodegradation problems. In this work, we have developed an effective approach to addressing this issue, by encapsulating a σ-platinated 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) photosensitizer into anthracene-based supramolecular polymeric systems. The platination effect enhances π-electron delocalization, while promoting intersystem crossing from singlet to triplet excited states. Accordingly, the σ-platinated BODIPY photosensitizer displays excellent 1O2 production capability, facilitating anthracene-to-endoperoxide transformation under low-energy irradiation conditions (λ = 520–590 nm). This leads to the breakup of supramolecular polymers and gels, which can be restored at room and elevated temperatures because of the reversible endoperoxide-to-anthracene deoxygenation process. Overall, the rational design of a σ-metalated photosensitizer opens up a new avenue to regulating the photoresponsiveness of supramolecular polymers under mild and nondestructive conditions.
Instrument
J-1500
Keywords
Circular dichroism, Polymers, Inorganic chemistry, Thermal stability,