Photoswitchable Exciton Coupling in Merocyanine–Diarylethene Multi‐Chromophore Hydrogen‐Bonded Complexes

Abstract

Licht an: Die Photokontrolle von J‐artigen Excitonen‐Wechselwirkungen gelingt mithilfe von Chromophoren (siehe Bild). Wasserstoffverbrückte Merocyanin‐Farbstoffe lassen sich durch photoinduzierten Ringschluss/Ringöffnung von Diarylethen‐Rezeptoren reversibel schalten. Die Zugabe von Bismelamin‐Rezeptoren, die eine H‐Aggregation induzieren, ermöglicht die partielle wechselseitige Umwandlung zwischen J‐ und H‐artiger Excitonenkopplung.

Recent advance of photochromic diarylethenes-containing supramolecular systems

“…The use of phototriggered conformational change of diarylethenes has been used to tune the physical properties of self-assembled supramolecular systems. Yagai and coworkers [24] reported merocyanine-diarylethene multi-chromophore complex between 2a and chiral diarylethene derivative 3, formed by hydrogen bonding interaction (Fig. 2), which cause a J-type aggregation of 2a.…”

“…The construction of stimuli-responsive supramolecular self-assembly has recently attracted significant interest because these assembles are promising candidates for smart materials that could find applications in chemistry, biology and material science [20][21][22]. By virtue of the significant difference of absorption spectra in open and closed forms, the morphology and chemical/physical properties of diarylethenes-based supramolecular assemblies, which are thermally irreversible, can be regulated by photoirradiation [23][24][25][26].…”

Photochemically colour-tuneable white fluorescence illuminants consisting of conjugated polymer nanospheres

“…Dithienylethene (DE) [9][10][11][12] is one of the most promising candidates for photochromic materials due to its good fatigue resistance, thermal stability and an ability to undergo conformational changes between open and closed forms via photoisomerization. DE derivatives are also known to show luminescent colour changes through photoisomerization [12][13][14][15][16][17][18][19][20][21][22] . Similarly, conjugated polymers containing DE moieties in the polymer backbones exhibit photochromism attributed to structural changes of the main chains 12,[23][24][25][26] .…”

Rational Design of Photoresponsive Supramolecular Assemblies Based on Diarylethene

“…[2] Although azobenzene derivatives have been widely used to design photoresponsive molecular assemblies due to their large structural changes accompanying cis/trans photoisomerization, [1] less attention has been devoted to diarylethenes [3] that show remarkable changes in optical properties and outstanding fatigue resistance for photoisomerization cycles, because of relatively small structural changes upon ring-closing/opening reactions. [4,5] Hydrogenbonding diarylethene organo-A C H T U N G T R E N N U N G gelA C H T U N G T R E N N U N G ators, in which higher gela-A C H T U N G T R E N N U N G tion ability was observed for the rigid closed isomer probably due to larger entropic penalty of the flexible open isomer upon aggregation, were report-ed by van Esch, Feringa and co-workers. [2d, 4a,b] A similar effect on the aggregation capability was observed for amphiphilic diarylethenes.…”