Optical-switchable energy transfer controlled by multiple-responsive turn-on fluorescence via metal–ligand and host–guest interactions in diarylethene-based [2]pseudo-rotaxane polymers. (4th November 2020)

• Record Type: Journal Article
• Authors: Singh, Ravinder; Xiao, Chi-Chong; Wei, Chong-Lun; Ho, Feng-Cheng; Khang, Trang Manh; Gouda, Chinmayananda; Wu, Tung-Kung; Li, Yaw-Kuen; Wei, Kung-Hwa; Lin, Hong-Cheu
• Is Part Of: Materials chemistry frontiers. Volume 5:Number 1(2021)
• Page Start: 438
• Page End: 449
• Publication Date: 2020-11-04
• Subjects: Materials science -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1039/d0qm00605j
• Languages: English
• ISSNs: 2052-1529

Abstract

Abstract : Multi-responsive and optically-active diarylethene (DAE)-based [2]pseudo-rotaxane polymers were prepared via host–guest interactions of Zn 2+ coordinated with two terpyridyl ligands bearing crown-ethers as an energy donor host and DAE containing two ammonium salts as an acceptor guest. Abstract : Multi-responsive and optically-active diarylethene-based [2]pseudo-rotaxane polymers Zn 2+ -TC2 /DS(O & C) were synthesized and prepared via metal–ligand and host–guest interactions, where Zn 2+ ion was coordinated with two ligands (TC ) containing a macrocyclic dibenzo-24-crown-8 (DB24C8 ) linked to a terpyridyl terminus to form a symmetrical host (Zn 2+ -TC2 ) and diarylethene (DAE) bearing two terminal secondary ammonium salts to form a symmetrical guest (DS ). Upon irradiation of UV-light ( λ = 355 nm), the prominent photo-induced electron transfer (PET) off process to promote optical-switchable Förster resonance energy transfer (FRET) process from the emissive metal-coordination Zn 2+ -TC2 host to the fluorescent DS(C) guest (in the closed form of emissive DAE unit) was explored for the multiple-responsive turn-on ratiometric fluorescence in supramolecular polymer Zn 2+ -TC2 /DS(C) . Remarkably, endowed with the novel features of reversible chemical/chelation-stimuli responsive dis-assembly/re-assembly of non-covalent interactions in response to pH/chelation, the polymer can be used for the sensing of pH and cyclen. Accordingly, the "molecular wire and stimuli-responsive effects" of diarylethene-based [2]pseudo-rotaxane polymer Zn 2+ -TC2 /DS(C) reveal significant supramolecular interactions to elucidate the turn-on fluorescence via the controllable FRET-ON process from Zn 2+ -TC2 host donor to PET-OFF DS(C) guest acceptor, which pave a promising route to elaborate optical-switchable supramolecular platforms for the future energy transfer applications.