A series of diaryl acenaphthylenes has been synthesized, and their photochromic properties are studied both in solution and in the crystalline state. 2,4-Dimethyl-5-phenylthiophene derivative 1a showed no photochromic reaction, while 2-methyl-5-phenylthiophene derivative 2a and 5-methyl-2-phenylthiazol derivative 3a showed reversible photochromism in solution. Fluorescence spectrum of compound 3a changed
Curves are ahead of the curve: Tetrathienylcorannulenecompounds showed highlysensitivephotochromism with a large molar absorption coefficient and a photocyclization quantum yield close to 1, although dithienyl phenanthrene compounds showed no photoreactivity. Such a high photoreactivity was rationalized by the predominance of the photoreactive atropisomers amplified by energy migration, and the
Investigations into oxidation induced ring opening of terarylenes containing π-extended thieno[<i>b</i>]thiophene units
作者:Colin J. Martin、Yora Goto、Ryosuke Asato、Gwénaël Rapenne、Tsuyoshi Kawai
DOI:10.1039/d2nj05726c
日期:——
Four photochromic terarylenes having extended π-conjugated thieno[b]thiophene units have been prepared. Photochromic ring-cyclization and cycloreversion behaviour are excluded depending on the position of thieno[b]thiophene units. A sponteneous fading reaction involving both thermal and cascade cycloreversion depending on molecular stucture is monitored. Electrochemical and computational studies have
已经制备了四种具有扩展的 π-共轭噻吩并 [ b ] 噻吩单元的光致变色杂萘嵌苯。根据噻吩并 [ b ] 噻吩单元的位置,排除了光致变色环环化和回环行为。监测涉及取决于分子结构的热和级联环化逆转的自发褪色反应。已经进行了电化学和计算研究,以阐明它们在两种异构体中的基态和阳离子态的相对稳定性。
Synthesis and Photochromic Properties of Diaryl [5]Helicene Derivatives
Diaryl [5]helicene derivatives demonstrate well-defined reversible photocyclization reactions with turn-off mode fluorescent photoswitching behaviors upon photochromic reaction. The loss of aromaticity of the central benzene ring of [5]helicene along with the photocyclization reaction the thermal bleaching rate.