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1.
2,6-二苯基苯酚是一种重要的精细化工中间体,随着经济的发展和科学技术的不断进步,它及其聚合物的用量和用途都在不断扩大拓宽。本文主要介绍了近年来它及其聚合物不同的合成路线及其优缺点,对它们在吸附材料、工程塑料、抗氧化剂、气体分离膜等方面的应用研究进展进行了总结,并对它们的应用前景进行了展望。  相似文献   

2.
应用熔融缩聚方法,用对苯二酚对硼硅氧烷聚合物进行改性,得到一种新型耐高温聚合物(PB)PH。并对其溶解性、热性能及其结构等作了详尽的论述。  相似文献   

3.
研究了2,6-吡啶二甲酸在玻璃电极上的电化学聚合物薄膜修饰电极的电化学特性,发现其对儿茶酚和对苯二酚析电化学氧化具有显著的催化作用,使它们的氧化电位降低,峰电流显著增大。从聚合物膜与多酚化合物的氢键作用对催化机理进行了探讨。该聚合物膜修饰电极可用于多酚的电化学测定。  相似文献   

4.
刺激响应型聚合物是一类功能性聚合物,它在药物控制释放、基因载体、纳米粒子以及纳米反应器等众多领域具有广阔的应用前景,因此引起了越来越多科学工作者的关注。刺激响应型聚合物多为双亲性聚合物,可通过自组装的方式得到形态各异的聚集体,如胶束、囊泡等。在受到某些外界环境刺激时,它们会产生特异性响应,尤其是功能性聚合物嵌段会发生相应的变化,从而引起整个聚合物结构的相转变和体积相转变。根据环境刺激种类的不同,刺激响应型聚合物可以分成不同类型,本文主要介绍了pH、温度、光、分子、电化学和手性等响应型聚合物,并概括了它们的结构特点以及不同的合成方法,简单说明了它们具有刺激响应功能的作用机理,阐述了结构与性能的联系。另外,还介绍了它们的潜在应用,并对此类聚合物的发展前景作了展望。  相似文献   

5.
在水热反应条件下合成了1种新颖的U(Ⅵ)-K异核配位聚合物[UO2K2(pdc)2(H2O)3]n(H2pdc=吡啶-2,6-二羧酸),通过元素分析、红外、紫外光谱及热重对该配合物进行了表征。单晶结构表明:配合物属于单斜晶系,C2/c空间群;晶胞参数分别为a=1.888 5(6)nm,b=1.490 0(5)nm,c=0.740 2(2)nm,β=111.104(10)°。中心铀及钾原子通过2个氮原子和6个氧原子与吡啶-2,6-二羧酸配体结合。不同的[UO2K2(pdc)2].3H2O单元通过氧原子桥联组成三维链状配位聚合物。配位聚合物中存在π…π相互作用及氢键作用。  相似文献   

6.
由于共轭聚合物的光致发光和电致发光性能, 有望成为制造全塑性发光二极管的材料, 因此近年来已引起人们的研究兴趣[1]. 聚乙炔是一种典型的共轭聚合物, 其不稳定性和难加工性限制了它的应用. 而含联苯液晶基元的取代聚乙炔, 不仅其难加工性得到了改善, 提高了稳定性, 而且赋予了聚合物液晶性, 因此有望开发出一批新型的高性能材料[2]. 目前对这类新型取代乙炔聚合物及其单体的凝聚态结构的报道还较少. 本文通过WAXD, TEM和AFM等手段对小分子液晶5-[4′-正庚基-氧-联苯基-4-氧-羰基]基-1-正戊炔(A3E′O7)的晶体结构进行了研究.  相似文献   

7.
由于共轭聚合物的光致发光和电致发光性能,有望成为制造全塑性发光二极管的材料,因此近年来已引起人们的研究兴趣[1].聚乙炔是一种典型的共轭聚合物,其不稳定性和难加工性限制了它的应用.而含联苯液晶基元的取代聚乙炔,不仅其难加工性得到了改善,提高了稳定性,而且赋予了聚合物液晶性,因此有望开发出一批新型的高性能材料[2].目前对这类新型取代乙炔聚合物及其单体的凝聚态结构的报道还较少.本文通过WAXD,TEM和AFM等手段对小分子液晶5-[4′-正庚基-氧-联苯基-4-氧-羰基]基-1-正戊炔(A3E′O7)的晶体结构进行了研究.1实验部分1.1样品及…  相似文献   

8.
吡啶-2,6-二甲酸经酯化,肼解得吡啶-2,6-二甲酰肼(2),(2)与芳香醛缩合得到了3个新的酰腙配体:吡啶-2,6-二甲酰肼苯甲醛腙(3a)、吡啶-2,6-二甲酰肼水杨醛腙(3b)和吡啶-2,6-二甲酰肼呋喃甲醛腙(3c),其结构经元素分析、IR、1HNMR和MS进行了确认。制备了吡啶-2,6-二甲酰肼与这三种新型配体的Tb(III)和Eu(III)配合物,并对配合物的溶液态的荧光性质进行了研究。结果表明,吡啶-2,6-二甲酰肼苯甲醛腙(3a)和吡啶-2,6-二甲酰水杨醛腙(3b)作为荧光敏化剂,对Eu3+和Tb3+的荧光敏化性能比吡啶-2,6-二甲酰肼以及大多数吡啶-2,6-二甲酸衍生物要好,是较理想的稀土荧光敏化剂,它们的稀土配合物在分子偶极矩较小的溶剂中荧光强度较强。  相似文献   

9.
配位聚合物有迷人的拓扑学结构和不同寻常的物理、化学性质,它们在主客体化学、磁性材料、超导材料、非线性光学材料、催化及生物活性等诸多方面都表现出极好的应用前景,吸引了许多国内外学者投入到这一领域进行研究[1-4]。到目前为止,人们已经制备出了大量的配位聚合物,并对其  相似文献   

10.
通过水热方法,采用H3CAM(H3CAM=4-hydroxy-pyridine-2,6-dicarboxylic acid)与Cd(NO3)2.4H2O反应,合成了1个镉配位聚合物[Cd4(HCAM)4(H2O)8]n(1),并对其结构和荧光性质进行了研究。结构分析结果表明该配合物属于单斜晶系,C2/c空间群。四个HCAM2-配体桥联4个镉离子形成了1个四核镉单元。这些孤立的单元通过氢键作用形成了1个三维配位框架。研究表明,该配合物在室温下能发出兰色荧光。  相似文献   

11.
A new method for synthesizing 2,6-dichlorodiphenylamine was presented in this article.2,6-dichlorodiphenylamine is the key intermediate for the preparing of diclofenac sodium.It was synthesized in a one-shot reaction with 2,6-dichlorophenol,a solution of sodium methoxide in methanol,methyl chloroacetate,aniline,and sodium hydroxide as raw materials by the acid-base neutralization,etherification,ammonolysis of ester,Smiles rearrangement of amide,and alcoholysis or hydrolysis of the rearrangement product.Based on many times of experiment,the best technological condition was found.The yield of target compound was about 91%.  相似文献   

12.
Convenient one-pot-two-step processes for chemical recycling of commercially available polyesters were conducted to produce the corresponding hydroxamic acids and hydrazides in high yields. Glycolysis of poly(ethylene 2,6-naphthalenedicarboxylate) in diethylene glycol into the corresponding oligomers, followed by aminolysis with hydroxylamine and hydrazine yielded 2,6-naphthalenedicarbohydroxamic acid in 96% and 2,6-naphthalenedicarbohydrazide in 85% overall yields. In a similar manner, terephthalohydroxamic acid and terephthalohydrazide were produced in 92 and 91%, respectively, from degradation of poly(tetramethylene terephthalate).  相似文献   

13.
Summary Treatment of 2-formyl-3-dimethylamino-propenenitrile (1a) and 2-ethoxycarbonyl-3-dimethylamino-propenenitrile (1b), resp., with substituted ureas led to the 2-cyano-3-ureidoacrylates2, which can be cyclized under alkaline conditions to give 5-formyl-5-cyano-, and 5-alkoxycarbonyl-2-oxopyrimidine derivatives3,6, and7. Reaction of3 with isopentylnitrite gave a mixture of the deaminated and oxidized product4 and the oxo derivative5, which was acetalized during the separation step. Similar reaction with the alkoxycarbonyl derivatives7 led to the formation of 1-alkyl-5-alkoxycarbonyl-pyrimidine-2,6-diones8a–d.
Synthesen mit Nitrilen, 95. Mitt.: Deaminierung von Cytosinderivaten
Zusammenfassung Die Reaktion von 2-Formyl-3-dimethylamino-propennitril (1a) und 2-Ethoxycarbonyl-3-dimethylamino-propennitril (1b) mit substituierten Harnstoffen führte zur Bildung der 2-Cyan-3-ureidoacrlate2, welche unter alkalischen Bedingungen zu den 5-Formyl-, 5-Cyan- oder 5-Alkoxycarbonyl-2-oxopyrimidinen3,6 bzw.7 cyclisiert werden konnten. Reaktion von3 mit Isopentylnitrit ergab eine Mischung aus deaminiertem und zugleich oxidiertem Produkt4 sowie dem Oxoderivat5, welches während der Säulentrennung auf Kieselgel zusätzlich acetalisiert worden war. Die ähnliche Reaktion mit den Alkoxycarbonyl-Derivativen7 führte zur Bildung der 1-Alkyl-5-alkoxycarbonyl-pyrimidin-2,6-dione8a–d.
  相似文献   

14.
Two independent synthetic pathways for the preparation of 4-methoxy, 4-benzyloxy and 4-hydroxy-2,6-difluoroanilines, versatile building blocks in medicinal chemistry, based on diazonium coupling or Curtius-type rearrangements are presented.  相似文献   

15.
Summary Alkylation of 8-vinyl-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione (1) with alkyl halides inDMF in the presence of potassium carbonate, or alternatively, alkylation of its sodium salt (2) with alkyl iodide or hydroxyalkyl iodide afforded the 7-alkyl- or 7-(-hydroxyalkyl)-8-vinyl-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-diones3. 2-Substituted oxiranes reacted with1 catalyzed by2 or Triton B to yield 7-(2-hydroxyalkyl)-8-vinyl-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-diones4. Compounds3 and4 were tested for broncholytic activity. The most effective derivatives were3c and4b.
7-Substituierte 8-Vinyl-1,3-dimethyl-3,7-dihydro-1H-purin-2,6-dione und ihre broncholytische Wirkung
Zusammenfassung Alkylierung von 8-Vinyl-1,3-dimethyl-3,7-dihydro-1H-purin-2,6-dion (1) mit Halogenalkanen in Gegenwart von Kaliumkarbonat inDMF oder Alkylierung seines Natrium-Salzes (2) mit Iodalkanen beziehungsweise Iodalkanolen führte zu den 7-Alkyl- bzw. 7-(-Hydroxyalkyl)-8-vinyl-1,3-dimethyl-3,7-dihydro-1H-purin-2,6-dionen3. 2-Substituierte Oxirane reagierten mit Verbindung1 unter Katalyse durch2 oder Triton B zu den entsprechenden 7-(2-Hydroxyalkyl)-derivaten4. Die Substanzen3 und4 wurden auf ihre broncholytische Wirkung geprüft. Die höchste Aktivität wurde bei den Derivaten3c und4b festgestellt.
  相似文献   

16.
2,6-Dimethylphenol polymerization with catalyst systems based on CuCl/n-butylamine were studied under 10 kg/cm2 pure oxygen pressure. By addition of sodium iodide, the catalyst performance was dramatically improved and an unusual long induction period was observed. Both the polymer intrinsic viscosity obtained and the induction period increased significantly with the increase of NaI concentration. However, the induction period decreased rapidly with the increase of n-butylamine concentration. UV-VIS absorption spectra showed that the CuCl/n-butylamine complex was converted to Cul/n-butylamine complex after the addition of NaI. The hydration rate of copper halide/n-butylamine complex decreased significantly with the increase of NaI and n-butylamine concentrations. Therefore the increase of polymer intrinsic viscosity and induction period by NaI addition suggest that the polymerization catalyst became more hydrolytically stable and less active at the higher NaI concentration. © 1996 John Wiley & Sons, Inc.  相似文献   

17.
The liquid product of the gas-phase amination of 2,6-diisopropylphenol (2,6-DIPP) to prepare 2,6-diisopropylaniline (2,6-DIPA) was analyzed using gas chromatography-mass spectrometry. Besides 2,6-DIPP and 2,6-DIPA, there are by-products such as water, 1,3-diisopropylbenzene, 2,6-diisopropylcyclohexamine in the liquid product, in which 2,6-diisopropylcyclohexamine is a major constitute by-product. The ratio of 2,6-diisopropylcyclohexamine to 2,6-DIPA is low when the reaction proceeds more completely at lower reaction space velocity, but this ratio increases when the reaction proceeds incompletely at higher space velocity. So that 2,6-diisopropylcyclohexamine is suggested to be the intermediate product of gas-phase amination of 2,6-DIPP. The reaction mechanism of gas-phase amination of 2,6-DIPP on the bifunctional palladium-lanthanum supported catalyst was proposed. This reaction was synergistically catalyzed by the Pd metal active sites that facilitated hydrogenation and dehydrogenation reactions and the acid sites on the catalyst support that accelerated isomerization and amination reactions.  相似文献   

18.
Ti, V, and Zr-HMS molecular sieves were prepared by grafting the respective metallocene onto the pure silica HMS, XRD, N2-physisorption, TEM, UV-Vis spectroscopy and elemental analysis were performed to characterize the samples prepared. The XRD patterns of the metal-grafted samples exhibited well-defined (100) reflections, and the intensity remained almost constant as with pure silica HMS. Surface area, hysteresis loop in N2 adsorption isotherms and N2 volume adsorbed decreased after metal grafting. The order of catalytic activity for 2,6-di-tert-butylphenol (2,6-DTBP) oxidation using H2O2 was V-HMS (91.5 % conversion) Ti-HMS(20.3 %) Zr-HMS(8.4 %). Metal leaching was detected for all the grafted samples in the reaction media; V-HMS(22 wt.%) Zr-HMS(3 wt.%) > Ti-HMS(2 wt.%). For V-HMS and Zr-HMS, further reaction after catalyst filtration indicated significant contribution to the reaction by the dissolved species.  相似文献   

19.
Raman spectrum of 2,6-difluorobenzonitrile in the powder form has been recorded in the region 50–4000 cm−1 on a Jasco K-500 spectrophotometer using the 488.0 nm radiation from an argon laser. IR spectra in the region 200–4000 cm−1 have been recorded in KBr pellet and nujol mull on a Nicolet DX spectrometer and in liquid and vapour phases on a Jasco FTIR/7000 spectrometer. Using these observed frequencies force field calculations for the planar and non-planar modes have been carried out assuming a general valence force field.  相似文献   

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