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11.
The maximum absorption wavelengths (lambda(a-max)), absorption coefficient (epsilon), maximum emission wavelengths (lambda(e-max)), fluorescent quantum yields (phi(f)), and second-order nonlinear polarizations (beta(xxx)) of seventeen 4,4'-bis-(2-(substituted-styryl))biphenyl and three 1,4-bis-(2-(substituted-styryl))benzene were measured. The results showed that some of this series of compounds possess high fluorescent quantum yields in DMF, such as, 2 (0.801), 3 (0.680), 5 (0.565), 15 (0.538) 16 (0.848), 18 (2.175), 19 (1.314) and 20 (1.060), as compared with quinine-sulfuric acid. They could be used as fluorescent whiteners and fluorescent colorants. Some of these compounds were of a high beta(xxx) values, such as in DMSO, 2 (29.00/10(-30) m(5)c(-1)), 3 (25.29/10(-30) m(5)c(-1)), 8 (21.79/10(-30) m(5)c(-1)) and 9 (24.08/10(-30) m(5)c(-1)). Electron-withdrawing substituent NO(2), which is attached to the two terminal phenyl rings could cause lambda(a-max) obviously to be shorter, but it made lambda(e-max) change longer. Electron-donating substituent at two end benzene rings, such as OCH(3), N((CH(3))(2)), even Cl, could make lambda(a-max) and lambda(e-max) longer, and the larger the electron-donating ability of the substituent, the longer the lambda(a-max) and lambda(e-max). This influence of 4-position substituent on lambda(a-max) or lambda(e-max) is obviously larger than that of 2-position substituent, and the action of substituent on 2-position is larger than that of substituent on 3-position. The values of lambda(a-max) and lambda(e-max) of biphenyl compounds 2 or 3 were respectively close to these values of corresponding benzene compounds 18 or 19.  相似文献   
12.
The biological importance of acetylcholine spurs the efforts to construct its synthetic receptors with the aims to develop acetylcholine sensor devices. Among the various building blocks used to synthesize artificial acetylcholine receptors, resorcin [4 ]arenes, [1] which can be conveniently obtained from the acid-catalyzed condensation of resorcinol with aldehyde, were shown to serve as one of the most strongest synthetic receptors for choline type guests.  相似文献   
13.
This communication describes the facile synthesis of tetracyanoresorcin[4]arene and its high and pH dependent affinities toward biologically important acetylcholine in the physiological pH region.  相似文献   
14.
一个得到1,1'-联-2-萘胺的合成新方法   总被引:3,自引:0,他引:3  
以2-萘胺为原料,在甲醇溶液中与1.5eq的CuCl2·2H2O反应,氧化偶合得到1,1'-联-2-萘胺(1)与CuCl2的络合物沉淀。沉淀依次经沸水和氨水处理,得到产率56%的1。  相似文献   
15.
苯并异喹啉酮衍生物的合成及其荧光性质;苯并咪唑苯并异喹啉酮;萘酰亚胺;荧光量子产率;亲核取代反应;合成  相似文献   
16.
The inclusion complexes of tetracyanoresorcin[4]arene with six quaternary ammonium cations—biologically important acetylcholine and choline, tetramethyl ammonium, tetraethyl ammonium, tetrapropyl ammonium and tetrabutyl ammonium—were studied by means of electrospray ionization mass, fluorescence and NMR spectrometries. The results indicate that tetracyanoresorcin[4]arene shows high affinity toward these ammoniums and is capable of recognizing their sizes.

Spectrometric evidences for the size discrimination of quaternary ammonium cations by tetracyanoresorcin[4]arene are preseneted.  相似文献   
17.
测定了8个吖啶酮类衍生物的紫外吸收光谱、荧光光谱和荧光量子产率,以研究它们的结构与光学性质之间的关系,用循环伏安法测出它们各自的电子势.发现吖啶酮类衍生物都具有较高的电子亲和势,表现出比常用的电子传输材料2-(4-联苯基)-5-(叔丁苯基1—1,3,4-二唑(PBD)更容易被还原的优良电化学性能。  相似文献   
18.
Copper amine complexes were used to mimic oxidases in the biomimetic oxidation of organic compounds[1]. Masahiro Noji and coworkers[2] reported the oxidative coupling of 2-naphthol into high yield of 1,1'-bi-2-naphthol (1) by using catalytical amount of CuCl-tetramethylethylenediamine complex at the presence of O2. Here we report the catalytic oxidation of 1 with copper amine complexes.  相似文献   
19.
许遵乐  黄乃正 《有机化学》1995,15(3):292-295
用乙酸钠作催化剂, 可使Azlatones 和低级醇顺利地进行酯交换反应. 文中分别使用带不同取代基的Azlatones在乙酸钠催化下与甲醇, 乙醇或乙二醇共热0.5~2.5小时, 以73~94%的分离产率制得21个酯交换产物.  相似文献   
20.
以甲酸为催化剂, 无需使用任何溶剂, 在室温条件下, 多种伯胺(包括脂肪胺、芳香胺)与2,5-己二酮发生Paal-Knorr缩合反应, 生成相应的吡咯衍生物. 该方法反应条件温和、操作简便、反应时间比较短、产物易于分离、收率高、环境友好.  相似文献   
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