Mechanistic Interplay between Light Switching and Guest Binding in Photochromic [Pd₂Dithienylethene₄] Coordination Cages

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(5), P. 2097 - 2103

Published: Jan. 8, 2019

Photochromic [Pd2L4] coordination cages based on dithienylethene (DTE) ligands L allow triggering guest uptake and release by irradiation with light of different wavelengths. The process involves four consecutive electrocyclic reactions to convert all chromophores between their open closed photoisomeric forms. So far, affinity the fully switched species was elucidated, but mechanistic details concerning intermediate steps remained elusive. Now, a new member DTE cage family allows unprecedented insight into interplay photoisomerization location inside/outside cavity. Therefore, intrinsic chirality backbones used as reporter for monitoring fate chiral guest. In its "open" form ( o-L, [Pd2( o-L)4] = o-C), C2-symmetric chromophore quickly converts energetically degenerate P M helical conformations. After binding homochiral 1 R-( -) or S-( +) camphor sulfonate R-CSA S-CSA), guest-to-host transfer observed via circular dichroism (CD) signal cage-centered absorption. Irradiating R/S-CSA@ o-C host-guest complexes at 313 nm produced configurationally stable "closed" photoisomers, thus locking induced an enantiomeric excess close 25%. This value (corresponding induction one out ligands), together DOSY NMR, ion mobility mass spectrometry, X-ray structure results, shows that closure first photoswitch is sufficient expel from

Language: Английский

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Photoresponsive Supramolecular Polymers: From Light‐Controlled Small Molecules to Smart Materials

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(10)

Published: Oct. 14, 2022

Photoresponsive supramolecular polymers are well-organized assemblies based on highly oriented and reversible noncovalent interactions containing photosensitive molecules as (co-)monomers. They have attracted increasing interest in smart materials dynamic systems with precisely controllable functions, such light-driven soft actuators, photoresponsive fluorescent anticounterfeiting light-triggered electronic devices. The present review discusses light-activated used their main photo-induced changes, e.g., geometry, dipole moment, chirality. Based these distinct formed by exhibit disassembly reassembly. As a consequence, polymerization, "depolymerization," regulation of the lengths topologies observed. Moreover, light-controlled functions polymers, actuation, emission, chirality transfer along length scales, highlighted. Furthermore, perspective challenges future opportunities is presented. Besides challenge moving from harmful UV light to visible/near IR avoiding fatigue, enabling biomedical applications, include actuators helical motion, light-modulated information transmission, optically recyclable materials, multi-stimuli-responsive systems.

Language: Английский

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Near‐Infrared Photodriven Self‐Sustained Oscillation of Liquid‐Crystalline Network Film with Predesignated Polydopamine Coating

Advanced Materials, Journal Year: 2020, Volume and Issue: 32(14)

Published: Feb. 20, 2020

Movement is one of the vital features living systems, and remote control bioinspired soft robotic systems in a precise, contactless harmless way extremely desirable but challenging. A near-infrared (NIR) photodriven polymeric oscillator designed fabricated by selectively coating mussel-inspired polydopamine (PDA) polymer layer on surface splay-aligned liquid crystalline network (LCN) film. The oscillating motions LCN oscillators can be facilely manipulated tuning light intensity film thickness. More importantly, programmability PDA enables behaviors to predesignated finely adjusted with locally repeatedly. self-oscillating movement mechanism attributed temperature oscillation at PDA-coated since it alternatively exposed sheltered NIR-light irradiations. Owing over 50% NIR irradiation solar spectrum, found oscillate upon exposure focused sunlight, presenting great potential fabrication power generation devices. This provides versatile strategy fabricate NIR-light-actuated oscillators, providing inspirations development biological robots advanced biomimetic

Language: Английский

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Circularly polarized luminescent self‐organized helical superstructures: From materials and stimulus‐responsiveness to applications

Aggregate, Journal Year: 2021, Volume and Issue: 2(6)

Published: Oct. 22, 2021

Abstract Circularly polarized luminescence (CPL) has gained considerable attention in various systems and rapidly developed into an emerging research field. To meet the needs of actual applications diverse fields, a high dissymmetry factor ( g lum ) tunable optical performance CPL would be most urgent pursuit for researchers. Accordingly, many materials strategies have been to address these critical issues. Emissive cholesteric liquid crystals (CLCs), that is, luminescent self‐organized helical superstructures, are considered ideal candidates constructing CPL‐active materials, as they not only exhibit values, but also enable flexible control CPL. This review mainly summarizes characteristics based on CLCs bulk phase doped with different emitters, including aggregated induced emission molecules, conventional organic small polymer metal–organic complex nanoparticles. In addition, recent significant progress stimulus‐responsive emissive terms several types stimuli, light, electricity, temperature, mechanical force, multiple stimuli is presented. Finally, short perspective opportunities challenges associated CLC field provided. anticipated offer new insights guidelines developing CLC‐based broader applications.

Language: Английский

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An Efficient Near‐Infrared Emissive Artificial Supramolecular Light‐Harvesting System for Imaging in the Golgi Apparatus

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(26), P. 10493 - 10497

Published: March 20, 2020

Abstract Light‐harvesting systems are an important way for capturing, transferring and utilizing light energy. It remains a key challenge to develop highly efficient artificial light‐harvesting systems. Herein, we report supramolecular co‐assembly based on lower‐rim dodecyl‐modified sulfonatocalix[4]arene (SC4AD) naphthyl‐1,8‐diphenyl pyridinium derivative (NPS) as platform. NPS donor shows significant aggregation induced emission enhancement (AIEE) after assembling with SC4AD. Upon introduction of Nile blue (NiB) acceptor into the NPS‐SC4AD co‐assembly, system becomes near‐infrared (NIR) emissive (675 nm). Importantly, NIR emitting NPS‐SC4AD‐NiB exhibits ultrahigh antenna effect (33.1) at high donor/acceptor ratio (250:1). By co‐staining PC‐3 cells Golgi staining reagent, NBD C 6 ‐ceramide, imaging in apparatus has been demonstrated using these nanoparticles.

Language: Английский

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