Fluorescence modulation by fast photochromism of a [2.2]paracyclophane-bridged imidazole dimer possessing a perylene bisimide moiety

Abstract

We demonstrated the red-color fluorescence switching of a perylene bisimide (PBI) derivative by using a fast photochromic [2.2]paracyclophane-bridged imidazole dimer.

Fast T-Type Photochromism of Colloidal Cu-Doped ZnS Nanocrystals

“…Among these, fast thermally reversible (T-type) photochromic compounds, whose time scales of the thermal back reactions are sub-microseconds to seconds (e.g. bridged-imidazole dimers, [5][6][7][8][9][10] oxazines, [11][12][13] and naphthopyran derivatives [14][15][16][17][18] ), are especially promising for ophthalmic lenses, fluorescence switches for bioimaging, 19,20 and holographic 3D displays. [21][22][23] These materials can tune colors and colorfading speeds from tens of nanoseconds to tens of seconds.…”

Highly transparent photochromic films with a tunable and fast solution-like response

“…The first approach consists in the synthesis of new photochromic molecules with minimal conformational changes along the photochromic interconversion to minimize the matrix effect. This has been mainly achieved with imidazole-based molecules, [21][22][23][24][25][26][27][28][29][30][31][32][33] prepared by Abe et al, or preventing the formation of the naphthopyrans (transoid-trans) [34][35][36][37][38][39][40][41][42][43] /spirooxazines (trans-merocyanines) 44,45 long-lived isomeric open form, responsible for the slowdown of the ring-closure reaction (oxazines, substituted…”

Solid Materials with Near‐Infrared‐Induced Fluorescence Modulation

“…On one hand, the interconversion of photochromic dyes are generally based on isomerization processes that involve large polarity and geometrical changes, which are often detrimentally affected by the surrounding matrix when these compounds are transferred from solution to the solid state. This is especially the case for photoswitchable luminescent materials based on T‐type photochromes, [ 26 ] for which novel strategies are being developed to favor dye (photo)isomerization in solid matrices (e.g., by covalently attaching bulky moieties to increase the surrounding free volume [ 22,27 ] or by using photoisomersable compounds with minimal conformational changes [ 26,28 ] ). On the other hand, photochromic dyes typically operate under highly energetic UV or visible radiation (e.g., spiropyrans) which contributes significantly to fast dye degradation.…”