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1.
朱万强  唐国风  勾华 《化学学报》2007,65(17):1875-1880
合成和表征了一类苯环上含F和CF3基团的1,3,4-噁二唑类化合物, 研究了它们的紫外-可见光谱、荧光光谱和电化学性质. 结果表明, 与不含氟的噁二唑化合物相比, 三氟甲基苯单元可降低化合物的LUMO能级, 而四氟苯单元则对化合物的光学和电化学性质无显著影响.  相似文献   

2.
陶敏莉  刘东志  张敏华  周雪琴 《化学学报》2008,66(10):1252-1258
以5-对氨基苯基-10,15,20-三苯基卟啉及2-苯基-5-(对氨基苯基)-1,3,4-噁二唑为原料合成了系列卟啉-噁二唑二元化合物, 其结构通过1H NMR, ESI-MS, IR, UV-Vis确定. 对合成化合物进行光谱性能测定, 结果表明, 在卟啉与噁二唑混合体系中, 存在着卟啉激发态分子向噁二唑基态分子的分子间电子传递过程, 导致卟啉激发态的荧光猝灭; 在卟啉-噁二唑二元体系中, 315 nm激发下发生了由激发态噁二唑基团至卟啉基团的能量传递, 导致噁二唑基团荧光猝灭, 卟啉基团荧光增强. 420 nm激发下不存在分子内卟啉基团向噁二唑基团的电子回传竞争; 电化学性能测定进一步表明从噁二唑基团向卟啉基团的电子传递是可能的. 因此卟啉-噁二唑二元化合物可能作为一种模型, 模拟光合作用中电子给体至叶绿素之间的电子传递过程.  相似文献   

3.
2,5-二芳基取代基-1,3,4-噁二唑类衍生物的合成与表征   总被引:2,自引:0,他引:2  
徐洪耀  沈娟  光善仪  李村 《合成化学》2006,14(1):14-17,22
以双酰肼环合法合成了含1,3,4-噁二唑结构单元的溴代芳卤,然后通过Sonogash ira钯催化偶联作用与不同单取代炔反应合成了3个新的2,5-二取代-1,3,4-噁二唑类小分子衍生物,其结构经DSC,1H NMR,IR和元素分析表征。  相似文献   

4.
合成了含偶氮苯基元的对称双噁二唑衍生物Fn,利用IR、1H NMR方法确认了其分子结构,用荧光光谱研究了偶氮苯基元对噁二唑衍生物光致发光特性的影响。 F3、F6、F10的发射峰皆为双峰,分别位于348、356 nm和345、357 nm及345、357 nm,属于噁二唑基团的特征发射峰。 偶氮苯基元的引入,对噁二唑衍生物Fn在溶液中的最大发射峰位影响较小,对发光强度影响较大,其发光强度大大降低。 这主要是由于在光激发过程中偶氮苯基团与噁二唑基团间发生了分子内电子能量转移。  相似文献   

5.
三芳基吡唑啉噁二唑类衍生物的合成及其荧光光谱研究   总被引:3,自引:0,他引:3  
提出了一种新的合成1,3,4-噁二唑化合物的方法,并通过Wittig反应将其与1,3,5-三芳基-2-吡唑啉相连合成了6种新的三芳基吡唑啉噁二唑类化合物.用红外光谱、质谱、核磁共振谱和元素分析对合成化合物进行了结构表征.用荧光光谱仪对它们的荧光性能进行了测试,测试结果表明目标产物具有良好的荧光性,其荧光发射波长均在437~511nm范围内,荧光量子产率最大可达0.36.  相似文献   

6.
将1,3,4-噁二唑基团引入二芳基乙烯分子中, 合成了2种新的二芳基乙烯类光致变色化合物1-氰基-2-(2H-5-苯基-1,3,4-噁二唑)-1,2-二(2,4,5-三甲基-3-噻吩)乙烯(3)和1,4-二{[1-氰基-2-(2H-5-苯基-1,3,4-噁二唑)-1,2-二(2,4,5-三甲基-3-噻吩)乙烯]-1,3,4-噁二唑}苯(4). 通过IR, NMR, MS和元素分析对化合物进行了结构表征, 并研究了其UV-Vis吸收、荧光发射、动力学特性和抗疲劳性质. 实验结果表明, 化合物[STHZ]3[STBZ]和[STHZ]4[STBZ]具有良好的光致变色性质, 光致变色闭环反应为零级反应, 开环反应为一级反应.  相似文献   

7.
聚芴基苯并唑类共聚物的合成和光物理性能   总被引:1,自引:1,他引:0  
通过溶液缩聚法合成了一系列不同组分的无规共聚物--聚对苯撑苯并二噁唑-co-聚(9,9-二辛基芴苯并二噁唑)(PBO-co-PBOF).利用X射线衍射、紫外-可见光吸收光谱、光致荧光光谱研究了不同组分和结构变化对聚合物形态和光物理性能的影响.结果表明:聚合物主链上辛基芴基团的引入使聚合物结构从晶态转变为非晶态.共聚物分...  相似文献   

8.
设计合成了三种1,2-亚乙基桥联咔唑和2,5-二芳基-1,3,4-噁二唑衍生物的双极传输材料,并通过核磁氢谱、碳谱、元素分析表征了它们的分子结构,研究了它们的紫外-可见吸收、光致发光、电化学和热稳定等性能.研究结果表明,这类双极传输材料具有咔唑和芳基噁二唑双功能基的紫外可见吸收和光致发光综合特性.热分解温度超过了340℃.与共轭基团桥联咔唑和芳基噁二唑的双极传输材料相比,HOMO/LUMO能级相应地提高,热稳定性能增强.  相似文献   

9.
利用生物活性亚结构拼接原理,将吡啶环、噻唑环引入到1,3,4-噁二唑母体结构中,设计并合成了一系列新型含吡啶(噻唑)的1,3,4-噁二唑衍生物.通过IR,1H NMR,EI-MS及元素分析等方法对所合成的化合物进行了结构表征.代表化合物2-(6-氯吡啶-3-甲硫基)-5-(吡啶-4-基)-1,3,4-噁二唑(I)经单晶X衍射证实了结构.初步测定了所合成化合物的杀菌活性,并比较了在1,3,4-噁二唑母体结构中引入噻唑杂环和引入吡啶杂环后其杀菌活性的差异.结果表明:目标化合物对测试的5种菌均具有一定的杀菌活性,对水稻纹枯病的抑制效果普遍优于对其它菌种的抑制效果;在1,3,4-噁二唑母体结构中引入噻唑杂环比引入吡啶杂环对其杀菌活性更有利.  相似文献   

10.
为了寻找高效安全的杀菌剂新品种和具有生物活性的新型先导化合物,根据活性亚结构拼接原理,将异噁唑和含氟基团引入到吡唑酰胺结构中,设计了13个未见文献报道的含异噁唑的二氟甲基吡唑酰胺类化合物,通过1H NMR,MS和HRMS对其结构进行了表征,并对目标产物进行了初步的生物活性测定.结果表明,在剂量为200 mg/L时,大部分化合物均表现出较高的杀菌活性.  相似文献   

11.
A change in the luminescence intensity of europium compounds was studied for the series of ligands β-diketones-their unsaturated analogues (monomers)-copolymers with styrene (methyl methacrylate). The optimal ratios of comonomers (1 : 2; 1 : 5) providing the maximum luminescence intensity of europium were determined. Europium (n x 10-3%) was determined in Ce, Pr, Nd, and Ho oxides, which are strong luminescence quenchers, using copolymers containing trifluoroacetylacetone and benzoylacetone.  相似文献   

12.
Hydrophilic copolymers containing 5-fluorouracil (5-FU), thymine, or adenine were prepared by the free-radical copolymerization of methacryloyl-type monomers containing them with water-soluble vinyl monomers such as acrylic acid, methacrylic acid, vinylpyrroli-done, acrylamide, and 4(5)-vinylimidazole with AIBN as initiator. Complex formation between the copolymers and RNA and between the copolymers having complementary nucleic acid bases in aqueous solution and a DMSO-ethylene glycol was studied by means of UV spectroscopy. These copolymers were found to release the N-hydroxyethyl derivatives of 5-FU, thymine, or adenine by hydrolysis of the ester of the polymer side chain under mild conditions. The effects of the kind of water-soluble comonomer, temperature, pH, and the imidazole group as catalyst on the hydrolysis of the ester are discussed.  相似文献   

13.
New copolymers containing oxadiazole, carbazole, and europium-containing fragments in the side chains were synthesized by ring-opening metathesis polymerization. The polymeric materials obtained were characterized by IR spectroscopy, GPC and DSC methods, and elemental analysis. All the copolymers possess strong metal-centered photoluminescence in solution and in thin film. In the electroluminescence spectra, the emission of the europium cations is exhibited and a broad band with the maximum at 507 nm is observed, which supposedly is attributable to the emission of the electroplexes between the polymeric matrix and the europium-containing fragments.  相似文献   

14.
Several models of monomers, homopolymers, and copolymers containing a photosensitizer group, 4-nitro-1-naphthyl-carbamoyl (NNC), have been synthesized. Synthetic methods are described, in addition to two routes for copolymers preparation. First, the radical copolymerization between monomers with the photosensitizer group built-in and comercial monomers such as styrene and methyl acrylate and, second, polymer modification by nucleophilic reaction between carbonyl group polymer supported and nitro-naphthyl amine. All products were characterized and one of the resulting soluble polymeric photosensitizer and its model compound, were tested as triplet energy donors against trans- stilbene and their Stern–Volmer constants were determined. Results show that the sensitizer efficiency is closer to that of the well known benzophenone sensitizer and higher than that of the acetophenone, while the sensitizer efficiency disminished when the chromophore is bonded to the polymer.  相似文献   

15.
Two phosphorus‐containing acrylate monomers were synthesized from the reaction of ethyl α‐chloromethyl acrylate and t‐butyl α‐bromomethyl acrylate with triethyl phosphite. The selective hydrolysis of the ethyl ester monomer with trimethylsilyl bromide (TMSBr) gave a phosphonic acid monomer. The attempted bulk polymerizations of the monomers at 57–60 °C with 2,2′‐azobisisobutyronitrile (AIBN) were unsuccessful; however, the monomers were copolymerized with methyl methacrylate (MMA) in bulk at 60 °C with AIBN. The resulting copolymers produced chars on burning, showing potential as flame‐retardant materials. Additionally, α‐(chloromethyl)acryloyl chloride (CMAC) was reacted with diethyl (hydroxymethyl)phosphonate to obtain a new monomer with identical ester and ether moieties. This monomer was hydrolyzed with TMSBr, homopolymerized, and copolymerized with MMA. The thermal stabilities of the copolymers increased with increasing amounts of the phosphonate monomer in the copolymers. A new route to highly reactive phosphorus‐containing acrylate monomers was developed. A new derivative of CMAC with mixed ester and ether groups was synthesized by substitution, first with diethyl (hydroxymethyl)phosphonate and then with sodium acetate. This monomer showed the highest reactivity and gave a crosslinked polymer. The incorporation of an ester group increased the rate of polymerization. The relative reactivities of the synthesized monomers in photopolymerizations were determined and compared with those of the other phosphorous‐containing acrylate monomers. Changing the monomer structure allowed control of the polymerization reactivity so that new phosphorus‐containing polymers with desirable properties could be obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2207–2217, 2003  相似文献   

16.
The new approach for synthesis of hyperbranched polymers from commercially available A2 and type monomers was extended to synthesize hyperbranched copolymers. In this work, hyperbranched copoly(sulfone-amine) was prepared by copolymerization of divinyl sulfone (A2) with 4,4′-trimethylenedipiperidine (B2) and N-ethylethylenediamine ( ). During the reaction, secon-dary-amino groups of B2 and monomers react rapidly with vinyl groups of A2 monomers within 35 s, generating a type of intermediate containing one vinyl group and two reactive hydrogen atoms. Now the intermediates can be regarded as a new type monomer, which further polymerizes to form hyperbranched copoly(sulfone-amine). The polymerization mechanism was investigated with FTIR and LC-MSD. The degree of branching (DB) of hyperbranched copolymers increased with decreasing the ratio of 4, 4′-trimethylenedipiperidine to N-ethylethyl- enediamine, so DB can be controlled. When the initial mole ratio of B2 to was equal to or higher than four, r≥4, resulted copolymers were semi-crystalline, while copolymers with r<3 were amorphous.  相似文献   

17.
Various aliphatic polyesters such as poly (ethyleneadipate), poly (tetramethylene adipate), poly (caprolactone), and poly (carbonate) were condensed with 4,4'-azobis-4-cyanopentanoyl chloride to prepare macro-azo-initiators. Their thermal properties, observed by differential scanning calorimetry, showed similar decomposition behavior to each other. Block copolymers containing each of these polyesters as a block segment combined with polystyrene or poly (methylmethacrylate) have been derived by the polymerization of monomers initiated with these macro-azo-initiators. © 1994 John Wiley & Sons, Inc.  相似文献   

18.
The synthesis of statistical and block copolymers, consisting of monomers often used as resist materials in photolithography, using reversible addition‐fragmentation chain transfer (RAFT) polymerization is reported. Methacrylate and acrylate monomers with norbornyl and adamantyl moieties were polymerized using both dithioester and trithiocarbonate RAFT agents. Block copolymers containing such monomers were made with poly(methyl acrylate) and polystyrene macro‐RAFT agents. In addition to have the ability to control molecular weight, polydispersity, and allow block copolymer formation, the polymers made via RAFT polymerization required end‐group removal to avoid complications during the photolithography. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 943–951, 2010  相似文献   

19.
The synthesis of styrenic monomers that have pyrazolic or bipyrazolic pendant groups is described. Their homopolymerization and their copolymerization with maleic anhydride (MA) and N-(3-acetoxy propyl) maleimide is reported. The monomers were prepared from the Williamson reaction between 2-pyridine carbinol, hydroxy monopyrazole, hydroxy bipyrazole, and chloromethyl styrene. The homopolymerizations of such styrenic monomers were tried under different conditions, which led to low molecular weight polymers with a high polydispersity. However, alternating copolymers were obtained using maleic anhydride or N-(3-acetoxy propyl) maleimide as comonomers, as shown by 1H-NMR, elemental analysis, and reactivity ratios r1 and r2. Furthermore, the hydrolysis of the acetate function of different copolymers was performed quantitatively. Unlike the acetoxy copolymers, such products do not have any glass transition temperature. Thermogravimetric investigations have shown that these copolymers exhibit good thermostability. © 1994 John Wiley & Sons, Inc.  相似文献   

20.
混合价黑色氧化铕的制备及其性质初步研究   总被引:2,自引:0,他引:2  
用含肼甲酸铕在N2气氛中热分解的方法制得了混合价黑色氧化铕粉末。对它的有关物理化学性质进行了初步研究,得到了相应的结论。  相似文献   

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