吸电子取代基位置对新型光致变色二芳基乙烯光电性能的影响,Physica Scripta

当前位置： X-MOL 学术 › Phys. Scripta › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

吸电子取代基位置对新型光致变色二芳基乙烯光电性能的影响
Physica Scripta ( IF 2.6 ) Pub Date : 2007-11-29 , DOI: 10.1088/0031-8949/2007/t129/062
G Liu ₁ , S Z Pu ₁ , C H Zheng _{1,

2} , Z G Le ₂ , M B Luo ₂

Affiliation

三种新的光致变色二芳基乙烯在两个末端苯环的邻位、间位或对位带有氰基，即 1,2-双（2-甲基-5-（2-氰基苯基）-3-噻吩基）全氟环戊烯（ 1a)、1,2-双(2-甲基-5-(3-氰基苯基)-3-噻吩基)全氟环戊烯(2a)和1,2-双(2-甲基-5-(4-氰基苯基)-3 -噻吩基）全氟环戊烯（3a），已被合成。系统地研究了取代基位置对其光电性能的影响，包括光致变色、荧光和溶液中的电化学性能。3a 的摩尔吸收系数（e = 7.48 × 104 L mol− 1 cm− 1）、吸收最大值和量子环化产率（Φ 0 − c = 0.53）最大，而其环回复量子产率（Φ c − 0 = 0.004) 是最小的。在己烷中，随着浓度的增加，二芳基乙烯 1a、2a 和 3a 的荧光发射峰显示出红移。二芳基乙烯 1a、2a 和 3a 的氧化起始电压分别为 1.85、1.58 和 1.58 V，高于它们的闭环形式 1b、2b 和 3b（分别为 1.61、1.43 和 1.49 V）。结果表明，二芳基乙烯1、2和3的光电特性明显不同，这可能是由于不同取代位置的氰基的吸电子能力和空间效应不同所致。

"点击查看英文标题和摘要"

Electron-withdrawing substituent position effect on the optoelectronic properties of new photochromic diarylethenes

Three new photochromic diarylethenes bearing cyano groups at the ortho-, meta-, or para-positions of both terminal phenyl rings, namely 1,2-bis(2-methyl-5-(2-cyanophenyl)-3-thienyl)perfluorocyclopentene (1a), 1,2-bis(2-methyl-5-(3-cyanophenyl)-3-thienyl)perfluorocyclopentene (2a), and 1,2-bis(2-methyl-5-(4-cyanophenyl)-3-thienyl)perfluorocyclopentene (3a), have been synthesized. The substituent position effects on their optoelectronic properties, including photochromism, fluorescence and electrochemical properties in solution, were investigated systematically. The molar absorption coefficient (e = 7.48 × 104 L mol− 1 cm− 1), the absorption maxima and the quantum cyclization yield (Φ 0 − c = 0.53) of 3a are the biggest while its cycloreversion quantum yield (Φ c − 0 = 0.004) is the smallest. In hexane, the fluorescent emission peaks of diarylethenes 1a, 2a and 3a showed a bathochromic shift upon increasing concentration. The oxidations of diarylethenes 1a, 2a and 3a are initiated at 1.85, 1.58 and 1.58 V, respectively, which are higher than those of their closed-ring forms 1b, 2b and 3b (1.61, 1.43 and 1.49 V, respectively). The results indicate that the optoelectronic features of diarylethenes 1, 2 and 3 are distinctly different, which may be attributed to the different electron-withdrawing ability and steric effect of cyano groups with different substituted positions.

更新日期：2007-11-29

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南