Twisted Donor−Acceptor Cruciform Luminophores Possessing Substituent-Dependent Properties of Aggregation-Induced Emission and Mechanofluorochromism
Twisted Donor−Acceptor Cruciform Luminophores Possessing Substituent-Dependent Properties of Aggregation-Induced Emission and Mechanofluorochromism
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扭曲的供体-受体十字形发光体具有取代基依赖性聚集诱导发射和机械荧光变色特性
DOI：
10.1021/acs.jpcc.7b11368
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Ling Zang
中科院分区：
文献类型：
--
作者：
Yonghui Wang;Defang Xu;Huaizhi Gao;Ying Wang;Xingliang Liu;Aixia Han;Chao Zhang;Ling Zang
合成了三种含施主-受体(D-A)结构的十字形发光团，分别命名为DHCS-BC、DMCS-BC和DTCS-BC，具有扭曲的分子构象。D-A型交叉共轭化合物表现出独特的分子内电荷转移(ICT)性质。有趣的是，它们表现出取代基依赖的聚集诱导发射(AIE)和机械荧光变色(MFC)行为。这三个十字形具有明显的AIE性质，其AIE因子分别为9、19和>；492，固体荧光量子产率分别为0.332、0.425和0.492。此外，它们的AIE活性按以下顺序递增：DHCS-BC<；DMCS-BC<；DTCS-BC；DTCS-BC，这与咔唑与取代氰基苯乙烯基之间的空间位阻引起的分子空间构象的扭曲程度和三个化合物的ICT程度一致。固体发射研究表明，经研磨和二氯甲烷(DCM)熏蒸处理后，其荧光颜色可在亮蓝绿(485 Nm)、亮蓝绿(479 Nm)、亮黄(526 Nm)和淡黄绿(524 Nm)、黄绿(534 Nm)、橙红(606 Nm)之间发生可逆变化，光谱红移分别为39、55和80 nm。这三个化合物的MFC活性按以下顺序递增：DHCS-BC<；DMCS-BC<；DTCS-BC；DTCS-BC，这是在外力刺激下分子构象平坦化和随后的平面分子内电荷转移(PICT)的结果。
Three donor–acceptor (D–A)-containing cruciform luminophores, namedDHCS-BC,DMCS-BC, andDTCS-BC, with twisted molecular conformation have been synthesized. The D–A-type cross-conjugated compounds showed unique intramolecular charge transfer (ICT) properties. Interestingly, they showed substituent-dependent aggregation-induced emission (AIE) and mechanofluorochromic (MFC) behavior. The three cruciforms possessed evident AIE nature with the AIE factors of 9, 19, and >492 and high solid-state fluorescence quantum yields of 0.332, 0.425, and 0.492, respectively. Moreover, their AIE activities increased in the orderDHCS-BC<DMCS-BC<DTCS-BC, which was consistent with the torsional degree of molecular spatial conformations induced by the steric hindrance between carbazole and substituted cyanostyryl and the ICT degrees of the three compounds. The solid emission studies illustrated that their fluorescence color could change reversibly between bright blue-green (485 nm), bright blue-green (479 nm), bright yellow (526 nm) and light yellow-green (524 nm), yellow-green (534 nm), orange-red (606 nm) through grinding and dichloromethane (DCM) fuming treatment, giving the large spectral red-shifts of 39, 55, and 80 nm, respectively. The MFC activities of the three compounds are increased with the sequence ofDHCS-BC<DMCS-BC<DTCS-BC, which was the result of the planarization of the molecular conformation and subsequent planar intramolecular charge transfer (PICT) under the external force stimuli.