A novel NIR violanthrone derivative with high electron-deficiency: effect of fluorescence on dicyanomethylene substitution
作者:Bo Liu、Duo Fan、Qiong Zhang、Yu Chen、Weihong Zhu
DOI:10.1007/s11458-010-0115-7
日期:2010.6
Near infrared (NIR) dyes attracted increasing interests in widely potential applications, such as fluorescent probe and living organism imaging, due to their low background signals from biomolecules, low light scattering and deep penetration, and low-cost excitation light sources. A novel NIR violanthrone derivative (VA-CN) with dicyanomethylene substitution was synthesized and fully characterized by 1H NMR, 13C NMR, HRMS, and IR spectrometry. It is demonstrated that the original planar conformation of violanthrone ring (the nine fused benzene rings) becomes twisted and unsymmetrical upon the incorporation of two strong electron-withdrawing dicyanomethylene units. Photophysical, electrochemical performances as well as distinct solvatochromic effects were studied in detail. Considering the low reduction potential (−0.56 V vs NHE), VA-CN could be considered as a good electron acceptor due to the strong electron deficiency resulted from dicyanomethylene group. A distinct increase in fluorescence was observed with 30-fold enhancement upon the addition of n-butyl amine. The reversible fluorescence “off-on” shows that VA-CN might be served as a promising fluorescent sensor for electron-rich amines.
近红外(NIR)染料因其来自生物大分子的背景信号低、光散射小、穿透力深、激发光源成本低等特点,在荧光探针和活体成像等广泛的潜在应用领域吸引了越来越多的关注。研究人员合成了一种具有二氰基亚甲基取代的新型近红外紫罗兰酮衍生物(VA-CN),并通过 1H NMR、13C NMR、HRMS 和 IR 光谱对其进行了全面表征。结果表明,在加入两个强夺电子的二氰基亚甲基单元后,紫罗兰酮环的原始平面构象(九个融合的苯环)变得扭曲且不对称。我们详细研究了这种化合物的光物理、电化学性能以及独特的溶解变色效应。考虑到 VA-CN 的还原电位较低(-0.56 V 对 NHE),由于二氰基亚甲基产生的强电子缺失,VA-CN 可被视为一种良好的电子受体。加入正丁基胺后,荧光明显增加,增强了 30 倍。这种可逆的荧光 "关闭-开启 "现象表明,VA-CN 可以作为一种很有前途的富电子胺荧光传感器。
Effect of substituents on the aggregate structure and photovoltaic property of violanthrone derivatives
In this paper, three violanthrone derivatives with different substituents, 16,17-bis(2-ethylhexyloxy)-anthra[9,1,2-cde-]benzo[rst]pentaphene-5,10-dione (3), 16,17-bis(octyloxy)-anthra[9,1,2-cde-]benzo[rst] pentaphene-5,10-dione (4), 16,17-bis(hexyloxy)-anthra[9,1,2-cde-]benzo[rst]pentaphene-5,10-dione (5), are synthesized. It is found that the substituent has a great effect on the aggregate structures of violanthrone derivatives: the shorter the side chain is, the stronger the intermolecular pi-pi actions in the solid state is. Because all compounds are p-type semiconductive materials with the relatively low-lying highest occupied molecular orbital (HOMO) energy levels (similar to-5.1 eV) and low band gaps (similar to 1.8 eV), their photovoltaic properties are evaluated when the blends of violanthrone derivatives and [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) (1:1, w/w) are used as the active layers of organic solar cells. Among three violanthrone derivatives, compound 5 exhibits the best photovoltaic performance with the power conversion efficiency (PCE) of 0.54% since the aggregate structure of compound 5 is in favor of charge transport. (C) 2012 Elsevier Ltd. All rights reserved.
DETERMINING THE QUANTITY OF A TAGGANT IN A LIQUID SAMPLE
申请人:Authentix, Inc.
公开号:EP3325947A1
公开(公告)日:2018-05-30
Determining the Quantity of a Taggant in a Liquid Sample
申请人:Conroy Jeffrey L.
公开号:US20130179090A1
公开(公告)日:2013-07-11
Device and methods for detecting/quantifying a fluorescent taggant in a liquid sample. Generally, the liquid samples are fuels having low concentrations (measured in ppb) of a fluorescent taggant. The detection/quantification generates a predicted concentration of the fluorescent tagging compound using a process selected from the group of a multivariate process, a background subtraction process, or a combination of both. The invention addresses the detection of an adulteration of gasoline and diesel fuels.