Colorimetric Detection of Nitroaromatics Using Organic Photochromic Compounds
作者:George Vamvounis、Nicholas Sandery
DOI:10.1071/ch15337
日期:——
An organic photochromic compound is explored as a new portable colorimetric sensor for nitroaromatics. This photochromic compound switches from colourless to pink upon exposure to ultraviolet light. In the presence of nitroaromatic explosive derivatives the photoswitching behaviour of the dithienylethene is suppressed, while a potential false positive (toluene) has little effect. The degree of photoswitching
一种有机光致变色化合物被用作硝基芳香族化合物的新型便携式比色传感器。该光致变色化合物在暴露于紫外线后会从无色变为粉红色。在硝基芳族炸药衍生物的存在下,二噻吩乙烯的光开关行为受到抑制,而潜在的假阳性(甲苯)几乎没有影响。通过将积分的可见光吸收量与分析物的浓度进行比较,得出伪斯特恩-沃尔默常数(K PSV),可以确定光开关抑制的程度。测得的K PSV s从12900(对硝基甲苯)到236 M –1不等 (甲苯),这与激发波长处的分析物吸收直接相关。
Synthetic protocol for diarylethenes through Suzuki–Miyaura coupling
The synthesis of a variety of diarylethenes through the SuzukiâMiyaura coupling reaction of 1,2-dichlorohexafluorocyclopentene with arylboronic acids and esters has been developed. Thiophenes with various substituents such as cyano and ester functionalities can be incorporated.
Effects of aromatic stabilization energies of aryl rings of symmetrical diarylethenes
作者:Huitao Xu、Shasha Wei、Congbin Fan、Gang Liu、Shouzhi Pu
DOI:10.1016/j.tet.2017.09.049
日期:2017.11
Four symmetrical diarylethenes bearing a variable aryl unit were synthesized and their crystal structures and photochromic performances were systematically studied to elucidate the effects of the aromaticstabilizationenergy (ASE) of aryl units. Experimental results revealed strong correlations of the thermal stability, as well as cyclization quantum yield, photoconversion ratio, and molar absorption
Photochromic and fluorescent properties of bisfurylethene derivatives
作者:Tadatsugu Yamaguchi、Masahiro Irie
DOI:10.1039/b611294c
日期:——
Photochromic diarylethenes having furan units (1 and 3) were synthesized and their photochromic performances were compared with those having thiophene units. The cyclization quantum yields of both derivatives in hexane are similar. In contrast, the cycloreversion quantum yield of the derivative having furan units (1) is much larger than that having thiophene units (2) in hexane. The difference is attributed to the conformation of the closed-ring isomers. Although 2a and 4a do not show any fluorescence, 1a and 3a exhibit fluorescence. Photochromism in the single crystalline phase was also observed for 1 and 3. Upon irradiation with 313 nm light, the colorless crystals 1 and 3 changed to violet and yellow, respectively.
Dithienylperfluorocyclopentene derivatives that bear alkyl substituents connected onto the two carbon atoms of the thiophene heterocycles where, in their ring-closed form, the new C–C single bond is formed (the 2-positions of the thiophene), can exhibit photochromic ring-closing, and both photochromic and electrochromic ring-opening.