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《有机化学》2016,(2)
Tr?ger’s bases(TB)具有特殊的刚性、立体Λ-型扭转构型,理论上,在分子堆积时其空间位阻作用不利于形成易引起"固态荧光淬灭"π-π密堆积,可以有效改善有机发光材料中常见的由π-π密堆积引起的固态荧光淬灭现象.选择Λ-型TB骨架作为分子的基本框架,首先以溴代Λ-型TB为原料合成了醛基取代的TB,再通过醛基-TB与取代苯乙腈类化合物经过简单的Knoevenagel缩合反应首次高效地合成了4个具有聚集态荧光增强特性的TB-氰基取代苯乙烯衍生物1a、2a、3a和4a,我们又通过钯催化的Heck偶联反应成功地将2-乙烯基噻吩引入到Λ-型TB中,合成了结构对称的D-π-C-π-D型TB衍生物5a,这些化合物均具有较大的Stokes位移.所有产物均通过1H NMR,13C NMR和HRMS等进行表征,并详细地对这些化合物的光电物理性质等进行了深入的研究,并重点探索验证了这些化合物的聚集诱导发光现象,它们在掺水聚集过程中均表现出明显的聚集荧光增强的性质,表明我们所合成的这些化合物均具有良好的聚集诱导发光性能(AIE).通过测试化合物1a、2a和5a在不同溶剂中的紫外吸收光谱和荧光光谱,表明化合物2a具有一定的溶剂效应,且这3个化合物的荧光发射峰位置都随着溶剂极性不同而发生变化,说明这些化合物存在着一定的ICT跃迁效应.通过对这些化合物的初步探究,希望这类新型固态发光TB衍生物能够在电致发光材料等领域具有潜在的应用价值. 相似文献
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设计并合成了1,8-二(2-吡咯酰胺)-3,6-二氯咔唑化合物(1), 利用X射线单晶衍射研究了该化合物的固态结构. 利用荧光和紫外-可见光谱技术及1H NMR滴定法研究了其对阴离子的识别. 研究结果表明, 化合物1对H2PO4-离子有较强的识别能力, 且对H2PO4-离子有明显的荧光增强效应, 可用来识别H2PO4-离子. 同时1H NMR滴定结果显示, 化合物1在阴离子识别过程中发生了构型转化. 相似文献
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用具有光学活性和生物学活性的2类化合物(取代)香豆素-3-甲酰氯和2-氨基苯并噻唑作用合成了4种新的兼具香豆素骨架和苯并噻唑基的化合物(3a-3d),用HRMS,IR和1H NMR对化合物结构进行了表征,确定了化合物的结构,并对其紫外吸收光谱和荧光光谱与分子结构的关系进行了讨论.研究发现:在紫外光谱中,新化合物(3a-3d)和2种原料化合物相比,因共轭链的增长而使其最大吸收波长(λmax)红移;4种化合物表现出比原料化合物较强的荧光性能,其中3c的荧光强度最大.文中给出了稀溶液中紫外光谱和荧光光谱相关的一些信息. 相似文献
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设计合成了系列含苯并咪唑单元的共轭结构化合物,用~1H NMR,~(13)C NMR,MS和元素分析进行了结构表征,测试了它们的紫外吸收波长(λ_a)、荧光发射波长(λ_e)、荧光量子产率(Φ)和荧光寿命(τ),讨论了分子结构与其光谱特性之间的关系.结果表明这类化合物能够表现出较强的发光性能,Φ值最高者达到0.91.以1,4-二-[2-(1-苄基苯并咪唑基)]苯(5b)制作出的有机发光二极管(OLED),其发光主峰在448 nm,在电压23.8 V(875 mA·cm~(-2))时最大亮度到达6790 cd·m~(-2),最大电流功效1.17 cd·A~(-1),最大功率效率0.96 lm·W~(-1),最大外部量子效率0.92%,这些数据表明该类化合物作为OLED材料具有较大的潜在应用价值. 相似文献
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Synthesis of Fluorescent 2,6‐Dicyano‐3,5‐Disubstituted Anilines Using Cellulose Sulfuric Acid in Aqueous Media 下载免费PDF全文
The synthesis of some fluorescent 2,6‐dicyano‐3,5‐disubstituted anilines using cellulose sulfuric acid (Cellulose‐SA) as an environmentally benign catalyst in H2O is described. The one‐pot reaction of 1,3‐diketone and three equiv. of malononitrile was carried out in the presence of one equiv. of a secondary amine, Cellulose‐SA as catalyst, and H2O as solvent. The photophysical properties (λAbs., λFlu.) of the synthesized compounds in CH2Cl2, MeCN, and MeOH have been measured. The emission spectra of the new compounds in the solid state are also reported. 相似文献
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Reductive coupling reaction of aryliminomethylferrocenes FcCH = NAr[(1, Ar=QHs (a), p‐ClC6H4 (b), p‐BrC6H4 (c), p‐CH3C6H4 (d), m‐ClC6H4 (e)] with triethyl orthoformate (2) in Zn‐TiCl4 system gave three kinds of products: 1, 3‐diaryl‐4, 5‐diferrocenyl imidazolidines (3), N, N‐disubstituted formamides (4), and 1, 2‐diferrocenyl ethylene (5). 1H NMR spectra proved that all the compounds 3 obtained were dl‐isomers. All the new compounds 3 and 4 were characterized by elemental analysis, 1H NMR, 13C NMR (for 3) and IR spectra. The molecular structure of 3c was determined by X‐ray diffraction. 相似文献
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合成了2-[2-(5-溴代噻吩-2-基)-乙烯基]-8-羟基喹啉(1)和2-[2-(5'-溴代二噻吩-5-基)-乙烯基]-8-羟基喹啉(2)两个新化合物; 利用IR, UV, 1H NMR, MS, 元素分析等确认其结构; 利用X射线单晶衍射仪测定了化合物1的晶体结构; 用MTT法评价了化合物1和2对鼠骨髓间质干细胞在不同浓度下的影响, 研究结果表明它们对鼠骨髓间质干细胞具有增殖作用. 化合物1和2与醋酸锌反应获得了其相应的锌配合物3和4, 光致发光显示: 它们的λmax分别是597和620 nm. 相似文献
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KOTESWARA RAO Valasani SUBBA REDDY Sanapalli DADA PEER Echchukattula JANARDHAN RAO Alahari NAGA RAJU Chamarthi 《中国化学》2009,27(12):2379-2384
Iminophosphocins 8a – 8e and 9a – 9e were synthesized in four‐step reactions via Staudinger reaction. 3‐(Bromomethyl)‐1,2,3,4,5‐pentahydro‐3λ5‐naphtho[1,8‐f,g][1,5,3]diazaphosphocin‐3‐one ( 3 ) was prepared by reacting tris(bromomethyl)phosphineoxide ( 1 ) with 1,8‐diaminonaphthalene ( 2 ) in the presence of triethylamine (TEA) in dry tetrahydrofuran (THF), and treated with L‐valine methyl ester ( 4 ) and bis(2‐chloroethyl)amine ( 5 ) in the presence of TEA in dry THF to get 3‐methyl‐2‐[(3‐oxo‐1,2,3,4,5‐pentahydro‐3λ5‐naphtho[1,8‐f,g][1,5,3]diazaphosphocin‐3‐yl)methylamino]butanoate ( 6 ) and 3‐[di(2‐chloroethyl)aminomethyl]‐1,2,3,4,5‐pentahydro‐3λ5‐ naphtho[1,8‐f,g][1,5,3]diazaphosphocin‐3‐one ( 7 ). The compounds 6 and 7 were treated with trichlorosilane (SiCl3H) in dry tetrahydrofuran (THF) to form the trivalent P(III) intermediates 8 and 9 , which were further treated with various alkyl azides in dry THF in 55–60°C to afford the title compounds 8a – 8e and 9a – 9e . Their structures were established by multi‐nuclear NMR and mass spectra. All the newly synthesized compounds were found to possess moderate anti‐microbial activity. 相似文献
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Ondřej Rudolf Vladimír Mrkvička Antonín Lyčka Michal Rouchal Antonín Klásek 《Helvetica chimica acta》2012,95(8):1352-1372
The Riemschneider reaction of 3‐thiocyanatoquinoline‐2,4(1H,3H)‐diones with conc. H2SO4 was investigated. Using different reaction conditions, 13 types of reaction products were isolated. Compounds bearing a Me, Et, or Bu group at C(3) afforded mainly [1,3]thiazolo[5,4‐c]quinoline‐2,4‐diones and 1,9b‐dihydro‐9b‐hydroxythiazolo[5,4‐c]quinoline‐2,4‐diones. In the case of the 3‐Bu derivatives of the starting compounds, C‐debutylation was also observed. If a Bn group is present at C(3), rapid C‐debenzylation of the starting thiocyanates occurred, yielding [1,3]oxathiolo[4,5‐c]quinoline‐2,4‐diones, and mixtures of mono‐, di‐, and trisulfides derived from 4‐hydroxy‐3‐sulfanylquinoline‐2‐ones. The reaction mechanism of all of the transformations is discussed. All new compounds were characterized by IR, 1H‐ and 13C‐NMR, and EI and ESI mass spectra, and in some cases, 15N‐NMR spectra were also used to characterize new compounds. 相似文献
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The interaction of Schiff base ligand A and its three metal complexes [A‐Fe(II), A‐Cu(II), and A‐Zn(II)] with bovine serum albumin (BSA) was investigated using a tryptophan fluorescence quenching method. The Schiff base ligand A and its three metal complexes all showed quenching of BSA fluorescence in a Tris‐HCl buffer. Quenching constants were determined for quenching BSA by the Schiff base ligand A and its metal complexes in a Tris‐HCl buffer (pH=7.4) at different temperatures. The experimental results show that the dynamic quenching constant (KSV) was increased with increasing temperature, whereas the association constant (K) was decreased with the increase of temperature. The thermodynamic parameters ΔH, ΔG and ΔS at different temperatures were calculated. The ionic strength of the Tris‐HCl buffer had a great influence on the wavelength of maximum emission of BSA. Under low ionic strength, the emission spectra of BSA influenced by A‐Zn(II) had a small blue shift. Compared to A‐Zn(II), the emission spectra of BSA in the presence of the Schiff base ligand A and A‐Cu(II) had no significant λem shift. At high ionic strength, the emission spectra of BSA upon addition of the Schiff base A, A‐Fe(II), and A‐Zn(II) all had a red shift, but the emission spectra of BSA had λem shift neither at low ionic strength, nor at high ionic strength in the presence of A‐Cu(II). Furthermore, the temperature did not affect the λem shift of BSA emission spectra. 相似文献
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Yun‐Hi Kim Sang‐Yun Jung Sung Ouk Jung Moon‐Hak Park Soon‐Ki Kwon 《Journal of polymer science. Part A, Polymer chemistry》2006,44(16):4923-4931
The new poly(arylene vinylene) derivatives, which are composed of biphenylene vinylene phenylene vinylene, biphenylene vinylene m‐phenylene vinylene, terphenylene vinylene phenylene vinylene, and terphenylene vinylene m‐phenylene vinylene as backbone and bulky fluorene pendants at each vinyl bridge, were designed, synthesized, and characterized. The obtained polymers showed weight‐average molecular weights of 11,100–39,800 with polydispersity indexes ranging from 1.5 to 2.1. The resulting polymers were amorphous with high thermal stability and readily soluble in common organic solvents. The obtained polymers showed blue emission (λmax = 456–475 nm) in PL spectra, and polymer 4 containing terphenylene vinylene m‐phenylene vinylene showed the most blue shifted blue emission (λmax = 456 nm). The double layer light‐emitting diode devices fabricated by using obtained polymers as emitter emitted bright blue light. The device showed turn on voltage around 6.5 V and brightness of 70–250 cd/m2. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4923–4931, 2006 相似文献
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《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(1):159-168
Lanthanum‐139 NMR spectra of stationary samples of several solid LaIII coordination compounds have been obtained at applied magnetic fields of 11.75 and 17.60 T. The breadth and shape of the 139La NMR spectra of the central transition are dominated by the interaction between the 139La nuclear quadrupole moment and the electric field gradient (EFG) at that nucleus; however, the influence of chemical‐shift anisotropy on the NMR spectra is non‐negligible for the majority of the compounds investigated. Analysis of the experimental NMR spectra reveals that the 139La quadrupolar coupling constants (CQ) range from 10.0 to 35.6 MHz, the spans of the chemical‐shift tensor (Ω) range from 50 to 260 ppm, and the isotropic chemical shifts (δiso) range from ?80 to 178 ppm. In general, there is a correlation between the magnitudes of CQ and Ω, and δiso is shown to depend on the La coordination number. Magnetic‐shielding tensors, calculated by using relativistic zeroth‐order regular approximation density functional theory (ZORA‐DFT) and incorporating scalar only or scalar plus spin–orbit relativistic effects, qualitatively reproduce the experimental chemical‐shift tensors. In general, the inclusion of spin–orbit coupling yields results that are in better agreement with those from the experiment. The magnetic‐shielding calculations and experimentally determined Euler angles can be used to predict the orientation of the chemical‐shift and EFG tensors in the molecular frame. This study demonstrates that solid‐state 139La NMR spectroscopy is a useful characterization method and can provide insight into the molecular structure of lanthanum coordination compounds. 相似文献
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A new thiotetrazole compound, 4‐((1‐phenyl‐1H‐tetrazol‐5‐ylthio)methyl) benzoic acid ( 1 ), has been synthesized and characterized by elemental analysis, 1H and 13C NMR, ESI‐MS, FT‐IR, UV–vis, fluorescence spectra, and single‐crystal X‐ray diffraction analysis. The structural analysis reveals that compound 1 adopts a nonplanar geometric structure and exhibits an extensive but not uniform π delocalization with all members of the tetrazolyl ring and the exocyclic sulfur atom. A density functional theory (DFT) calculation at B3LYP/6‐31G** level of theory was performed to elucidate the structure of this thiotetrazole system. And the time‐dependent DFT (TD‐DFT) calculations of absorption spectra reveal two electron‐transition bands derived from the contribution of π → π* transitions, which are in agreement with experimental results. Moreover, compound 1 exhibits a blue‐light emission (λem = 441 nm) in the solid state at room temperature. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:435–443, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21034 相似文献
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Synthesis,spectral, DFT calculations and antibacterial studies of Fe(III) complexes of new fluorescent Schiff bases derived from imidazo[4',5':3,4]benzo[1,2‐c]isoxazole 下载免费PDF全文
New fluorescent heterocyclic ligands were synthesized by the reaction of 8‐(4‐chlorophenyl)‐3‐alkyl‐3H‐imidazo[4',5':3,4]benzo [1,2‐c]isoxazol‐5‐amine with p‐hydroxybenzaldehyde and p‐chlorobenzaldehyde in good yields. The coordination ability of the ligands with Fe3+ ion was examined in an aqueous metanolic solution. Schiff base ligands and their metal complexes were characterized by elemental analyses, IR, UV–vis, mass, and NMR spectra. The optical properties of the compounds were investigated and the results showed that the fluorescence of all compounds is intense and their obtained emission quantum yields are around 0.15 – 0.53. Optimized geometries and assignment of the IR bands and NMR chemical shifts of the new complexes were also computed by using density functional theory (DFT) methods. The DFT‐calculated vibrational wavenumbers and NMR chemical shifts are in good agreement with the experimental values, confirming suitability of the optimized geometries for Fe(III) complexes. Also, the 3D‐distribution map for HOMO and LUMO of the compounds were obtained. The new compounds showed potent antibacterial activity and their antibacterial activity (MIC) against Gram‐positive and Gram‐negative bacterial species were also determined. Results of antibacterial test revealed that coordination of ligands to Fe(III) leads to improvement in the antibacterial activity. 相似文献