Supramolecular inclusion complexes of β-cyclodextrin with bathochromic-shifted photochromism and photomodulable fluorescence enable multiple applications

Abstract

Three distinct viologen derivatives have been designed and successively synthesized. They are shown to form 1:1 or 2:1 host−guest inclusion complexes with β-cyclodextrin (β-CD) in aqueous solution. In comparison with...

Acid–base regulated inclusion complexes of β-cyclodextrin with 1-[2-(4-fluorophenyl)-2-oxoethyl]-4,4′-bipyridinium dichloride displaying multistimuli-responsive chromic behaviors and photomodulable fluorescence

“…Clearly, these ESR signals account for the generation of the organic radicals FOV + ˙ and FHV˙, which may originate from the photo-induced electron transfer from the oxygen atoms of the host β-CD to the pyridinium unit of the guests. 47–49 When the inclusion complexes recover to their original colors in air, their ESR signals disappear. Obviously, the generated organic radicals in photoproducts can be quenched by oxygens in the air.…”

“…36–42 By using a supramolecular strategy of incorporating photoresponsive guests into macrocycle hosts, we and others recently have fabricated a series of host–guest photochromic materials that undergo specific color changes between two distinct states upon the light irradiation. 42–52 In the present work, to pursue an effective multistimuli-responsive chromic material, we prepared a guest molecule 1-[2-(4-fluorophenyl)-2-oxoethyl]-4,4′-bipyridinium dichloride (FOV·Cl 2 , Fig. S1 and S2, ESI†) by combining together two functional groups (see Experimental), one being 4,4′-bipyridinium and the other one being 4-fluoroacetophenone.…”

Three Viologen Compounds Containing Keggin and Mo-Capped Weakley Polyoxometalates: Photo-/Thermo-/Electro-Chromic Studies

“…Because of their reversible color change under the stimulation of light, heat, and other external environments, color-changing materials are kinds of good smart materials for anticounterfeiting. − As a kind of good color-changing material, viologen (1,1′-disubstituted-4,4′-bipyridiniums) compounds have been widely used in multiple fields, such as ink-free erasable printing, intelligent windows, color-changing devices, and other fields. − Viologen compounds generally have reversible color changes, thus they possess the potential as anticounterfeiting materials. , In 2021, Zang’s group prepared the first indium-based organic–inorganic hybrid color-changing material by using the viologen system, which has both photochromic and electrochromic properties and was successfully applied in the field of ink-free erasable printing. In 2020, Zhang’s group synthesized a polyoxometalate (POM)-based photochromic material through using a viologen ligand and applied it in the field of ink-free erasable printing with high stability, which can be read by the human eyes.…”