Preparation of Dithienylethene with Amino Groups, and Photochromic Behavior in Langmuir-Blodgett Film of the Amphiphilicdithienylethene

We successfully synthesized dithienylethene with amino groups. Then, we successfully prepared Langmuir-Blodgett (LB) films of the dithienylethene having ammonium cation group when dodecyl benzene sulfonic acid was employed as an anionic counter ion. From X-ray diffraction profiles, however, it was demonstrated that they did not form well-defined layered structure;X-ray diffraction peaks were much broadened. Photochromic behavior was confirmed in the LB films. Unfortunately, the LB films were not so stable;photochromic reaction was observed only several times in the LB films.

Efficient blue light-responsed dithienylethenes with exceptional photochromic performance

Three novel dithienylethenes modified by bifluoroboron β-diketonate fragments have been successfully developed. Upon blue light irradiation, they reached photostationary state within 2-5 s, as well as 100% conversion ratio and photocyclization quantum yield of > 0.70. Such fascinating photochromism were endowed by collaborative role of electron-withdrawing effect of BF_(2)bdk group to reduce HOMO-LUMO electronic gap for the open isomer, together with intramolecular hydrogen bonds and CH-π interactions favoring antiparallel conformation fixation. Moreover, they displayed specific discrimination and photoswitchable bacterial imaging for S. aureus.

Dithienylethene metallodendrimers with high photochromic efficiency

It has been challenging to achieve multi-photochromic systems without affecting the individual photoswitching properties of the constituent units. Herein, we present the design and synthesis of a new family of platinum-acetylide dendrimers containing up to twenty-one photochromic dithienylethene(DTE)units that exhibit both high photochromic efficiency and individual switching properties. Upon irradiation with ultraviolet(UV) and visible(vis) light, the resultant metallodendrimers display high conversion yield and good fatigue resistance. More interestingly, cyclization-cycloreversion kinetics revealed that the photochromic property of each DTE unit in these metallodendrimers is unaffected by its neighbor and the full ring-closure of up to twenty-one DTE units in one single dendrimer has been achieved.

Novel Macrocycles Bearing Dithienylethene Units and Urea Functional Groups Synthesis, Structure and Photochromic Property

Two novel photochromic macrocycles 1 and 2 bearing dithienylethene units and urea building blocks have been synthesized, and their photochromic properties are described. Macrocycle 2 shows good photochromic properties, while the relatively smaller size of macrocycle 8h exhibits photochemically inactive properties due to the unfa- vourable ring conformational constraint. Moreover, the crystal structures of the urea-protected precursor macrocyles 3a, 3h, and 8b are presented.

The magic of integration:Exploring the construction of dithienylethene-based infinite coordination polymers and their synergistic effect for gaseous ammonia probe applications

Infinite coordination polymers are recognized as excellent platform for functionalization.Dithienylethene motifs,which are one of the most attractive functional moieties,were incorporated into an infinite coordination polymer,to deliver a‘‘smart’’porous material that can response to external stimuli.The obtained dithienylethene-based infinite coordination polymers（named Cu-DTEDBA）share the advantages of both infinite coordination polymers（porosity and stability）and dithienylethene motifs（photochromism）.The physical and chemical properties of Cu-DTEDBA were characterized by FTIR,TEM,SEM,XRD,TGA,UV–vis,EDX and BET.Moreover,the combination of dithienylethene and infinite coordination polymers gives rise to a synergistic effect,which induces functional behaviors of ammonia sensor applications.Both open and closed forms of Cu-DTEDBA exhibit distinct colorimetric change upon exposure to gaseous ammonia,which is not observed in dithienylethene free molecules.