Several difurylperfluorocyclobutenes showing reversible photochromism were synthesized. In comparison to their cyclopentene homologues they show enhanced quantum yields for ring opening but reduced quantum yields for ring closure. X-ray structure analysis and quantum chemical calculations provide a conclusive explanation for such a behaviour.

Thiazole orange-modified diarylethene (1) shows weak fluorescence but no photochromism in aqueous solution. When binding with DNA, the fluorescence of 1 is enhanced drastically and the photochromic reactivity is unlocked. This kind of DNA-responsive photoswitchable system can be used for imaging nucleic acids within cells.

Here we report the first photochromism of a newly designed [2.2]paracyclophane-bridged imidazole dimer in water. The photochromic dye with a hydrophilic and a hydrophobic substituent forms vesicles in water and shows instantaneous colouration upon UV light irradiation and successive rapid fading in the dark.

Abstract Photo-stimuli response in materials is a fascinating feature with many potential applications. A photoresponsive gel of poly(heptazine imide), PHI, termed PHIG, exhibits photochromism, photoconductivity, and photo-induced charge accumulation, generated using ionic liquids PHI. Although there are several examples liquid gels that exhibit photochromism this the first report an both these...

A newly synthesized dipyrrinone derivative bearing an ethoxycarbonyl group at the pyrrolic-α position exhibited solvent-dependent dual-mode photochromism between T- and P-types. While this molecule underwent thermally reversible (T-type) photoresponsive reaction in chloroform, it became a thermally irreversible (P-type) system in methanol.

Three dithienylethene derivatives having anthracene substituents (connected at 1-, 2- and 9-positions) were prepared. Although these three derivatives exhibit photochromic reactivity in solution, only one of the derivatives (connected at 2-position) undergoes the photochromic reaction in the crystalline phase. X-Ray crystallographic analysis and DFT calculation revealed that conformation of the...

We report a new type of fast photochromic imidazole dimer, pentaarylbiimidazole (PABI), which shows a few μs fast photochromism with high fatigue resistance against light irradiation. PABI has an unusual spiroconjugated imidazoisoindole skeleton and its derivatives can be prepared by simple synthetic procedures.

Photochromism in a diarylethene derivative (1O) can be gated by a host-guest interaction where the thiazole orange groups are bound into the hydrophobic cavity of CB[8] in water. The closed-ring isomer (1C), which cannot be obtained freely in aqueous solution, survives even when the complex is dissociated by displacement from CB[8] by competition with 1-adamantanamine hydrochloride.