共查询到20条相似文献,搜索用时 125 毫秒
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苯胺电化学聚合机理的研究 总被引:8,自引:0,他引:8
主要应用电化学方法研究了苯胺及其电化学聚合产物─—聚苯胺的循环伏安曲线,同时讨论了苯胺的存在对4-氨基二苯胺循环伏安曲线的影响。结果表明:随着苯胺聚合的进行,聚苯胺同时发生降解;苯胺电化学聚合按“白催化机理”进行。 相似文献
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芳胺常压气相N-烷基化反应研究 总被引:1,自引:0,他引:1
在固定床催化反应器中常压下研究了芳胺和醇的气相法N-烷基化反应。考察了γ-Al2O3系列催化剂的反应性能,筛选出了两种适用于苯胺N-甲基化反应且性能较好的催化剂。反应条件为:在甲醇和苯胺的摩尔比为31时,反应温度为280℃,液时空速为0.3h-1的条件下,苯胺转化率为99%,生成N,N-二甲基苯胺(DMA)的选择性为92%。研究了甲醇和芳环上不同位置取代的甲基苯胺的反应规律,其转化率顺序:苯胺≈对一甲苯胺≈间-甲苯胺>邻-甲苯胺。从C1到C4不同结构的醇和苯胺反应的规律研究,证明随醇中碳原子数目的增加,醇的反应活性降低,正构醇和苯胺反应和异构醇与苯胺反应随温度升高的变化趋势相反。 相似文献
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The water‐soluble phosphine ligands, 1,3,5‐triaza‐7‐phosphatricyclo[3.3.1.13,7]decane (tpa) and 1‐alkyl‐1‐azonia‐3,5‐diaza‐7‐phosphatricyclo[3.3.1.13,7]decane iodides (Rtpa+I−), with alkyl=methyl(mtpa+I−), ethyl (etpa+I−) and n‐propyl, (ptpa+I−), and mtpa+Cl− react with [Rh2Cl2(CO)4] giving the rhodium(I) complexes [RhCl(CO)(tpa)2], [RhI(CO)(Rtpa+I−)2], [RhCl‐(CO)(mtpa+Cl−)3] and [RhI(CO)(Rtpa+I−)3]. The properties and reactivities of the complexes have been investigated using 1H and 31PNMR and IR spectroscopies. The five‐coordinate complexes in solutions show dynamic properties. The complexes are catalysts of the water‐gas shift reaction, the hydrogenation of CC and CO bonds, the hydroformylation of alkenes and the isomerization of unsaturated compounds. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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2-脱氧-烟酰胺基-β-D-氨基葡萄糖的合成和表征 总被引:1,自引:0,他引:1
A new nicotinic acid derivative,2-deoxy-2-nicotinoylamido-β-D-glucopyranose, was synthesized with β-configuration exclusively. The structure and properties of the product were characterized by ^1H NMR, PT-IR, MS, DSC and polarimeter. The details of ^1H NMR spectrum and the mass spectrum proved that there are a great amount of hydrogen bonds in the product. 相似文献
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New crown ether carrying two fluorionophores of cis‐dibenzothiazolyldibenzo‐24‐crown‐8 was synthesized from cis‐diformyldibenzo‐24‐crown‐8 and 2‐aminobenzenethiol. The binding behavior and the optical properties of the crown ether were examined through UV‐visible spectroscopy and fluorescence spectroscopy. When complexed with Na+, K+, Rb+, and Cs+ ions, it led to intramolecular charge transfer and caused the changes of the fluorescence spectra. The protonation of the crown ether was also studied. With protonation using CF3COOH, the absorption bands and the fluorescence spectroscopy changed, the maximal fluorescence wavelengths red shifted and the fluorescence intensity with the maximum at 433 nm enhanced strongly. J. Heterocyclic Chem., (2011). 相似文献
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A new crown ether of 2,13‐dibenzothiazol‐2′‐yldibenzo[b,k]‐18‐crown‐6 was synthesized from 2,13‐diformyl‐ dibenzo[b,k]‐18‐crown‐6 with 2‐aminothiophenol. The binding behavior and the optical properties of the crown ether were examined through UV‐visible spectroscopy and fluorescence spectroscopy. When complexed with Na+, K+, Rb+ and Cs+ ions, it led to intramolecular charge transfer and caused the changes of the fluorescence spectra. The protonation of the crown ether was also studied. 相似文献
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《Magnetic resonance in chemistry : MRC》2003,41(4):301-303
4‐Methyl‐6,8‐dihydroxy‐7H‐benz[de]anthracen‐7‐one was isolated from the sap of Aloe by column chromatography. Its 1H and 13C NMR spectra were completely assigned by utilizing two‐dimensional 1H‐detected heteronuclear one‐bond (HMQC) and multiple‐bond (HMBC) chemical shift correlation experiments together with 1H–1H COSY and DEPT techniques. These techniques were also valuable in assigning the protons and carbons of those benzanthrone compounds which were previously incompletely reported because of the overlap of proton signals. The molecular structure was elucidated by 2D NMR analysis. The spectral properties (MS, IR and UV) are also presented. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Eduardo Corts Corts Rafael Sosa Mendoza Maximiliano Santibez Gutirrez Olivia Garca‐Mellado De Corts 《Journal of heterocyclic chemistry》2004,41(2):273-276
The preparation and spectral properties often novel methyl 5‐[(o‐, m‐, and p‐substituted)‐phenylthio]‐2‐benzimidazolecarbamates with possible pharmacological activity as antihelmintics is described; by condensation and cyclization between 5‐methylthioures sulfate chloroformic acid methyl ester and 3,4‐diaminophenyl‐substituted‐phenylthio ether dissolved in ethanol. The structures of all final products were corroborated by ir; 1H‐nmr, 13C‐nmr and ms. 相似文献
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Viktor A. Tafeenko Stanislav I. Gurskiy Andrey N. Baranov Tatiana V. Kaisarova Leonid A. Aslanov 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(2):m52-m55
The structures of three salts of 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate with alkali metals (Na, K and Rb) are related to their luminescence properties. The Rb salt, rubidium(I) 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate, Rb+·C8HN4O2−, is isomorphous with the previously reported potassium salt. For the Na compound, sodium(I) 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate dihydrate, Na+·C8HN4O2−·2H2O, two independent sodium ions, located on inversion centers, are coordinated by four water molecules each and additionally by two cyano groups for one and two carbonyl groups for the other. The luminescence spectra in solution are unaffected by the nature of the cation but vary strongly with the dielectric constant of the solvent. In the solid state, the emission maxima vary with structural features; the redshift of the maximum luminescence varies inversely with the distance between the stacked anions. 相似文献
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Eduardo Cortas Cortas Ana María Hernndez Sanabria Olivia García Mellado 《Journal of heterocyclic chemistry》2002,39(1):55-59
The preparation of twelve novel 2,3,4,5,10,11‐hexahydro‐1H‐dibenzo[b,e] [1,4]diazepin‐l‐ones which have potentially useful pharmacological properties; by condensation and cyclization between 3‐{[4‐(o‐; m‐; p‐methoxy)phenylthio]‐1,2‐phenylenediamine}‐5,5‐dimethyl‐2‐cyclohexenone with (o‐; and p‐substi‐tuted)benzaldehyde. The structure of all final products were corroborated by ir, 1H‐nmr, 13C‐nmr and ms. 相似文献
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Coordination‐Driven Self‐Assembly of Carbazole‐Based Metallodendrimers with Generation‐Dependent Aggregation‐Induced Emission Behavior
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Wen‐Jia Fan Bin Sun Jianqiu Ma Prof. Dr. Xiaopeng Li Prof. Dr. Hongwei Tan Prof. Dr. Lin Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(37):12947-12959
A new family of 120° carbazole‐based dendritic donors D1 – D3 have been successfully designed and synthesized, from which a series of novel supramolecular carbazole‐based metallodendrimers with well‐defined shapes and sizes were successfully prepared by [2+2] and [3+3] coordination‐driven self‐assembly. The structures of newly designed rhomboidal and hexagonal metallodendrimers were characterized by multinuclear NMR (1H and 31P) spectroscopy, ESI‐TOF mass spectrometry, FTIR spectroscopy, and the PM6 semiempirical molecular orbital method. The fluorescence emission behavior of ligands D1 – D3 , rhomboidal metallodendrimers R1 – R3 , and hexagonal metallodendrimers H1 – H3 in mixtures of dichloromethane and n‐hexane with different n‐hexane fractions were investigated. The results indicated that D1 – D3 featured typical aggregation‐induced emission (AIE) properties. However, different from ligands D1 – D3 , metallodendrimers R1 – R3 and H1 – H3 presented interesting generation‐dependent AIE properties. Furthermore, evidence for the aggregation of these metallodendrimers was confirmed by a detailed investigation of dynamic light‐scattering, Tyndall effect, and SEM. This research not only provides a highly efficient strategy for constructing carbazole‐based dendrimers with well‐defined shapes and sizes, but also presents a new family of carbazole‐based dendritic ligands and rhomboidal and hexagonal metallodendrimers with interesting AIE properties. 相似文献
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《Journal of polymer science. Part A, Polymer chemistry》2018,56(9):1012-1019
Herein, we report the synthesis, characterization, and field‐effect properties of two cross‐conjugated dithienylmethanone (DMO)‐based alternating polymers, namely, PDMO‐S and PDMO‐Se . Both polymers possess high thermal stability, good solubility, and broad absorption spectra. Their electrochemical properties were investigated using cyclic voltammetry, indicating that PDMO‐Se has higher HOMO/LUMO energy levels of −5.49/−3.49 eV than −5.57/−3.58 eV of PDMO‐S . The two polymers exhibited promising charge transport properties with the highest hole mobility of 0.12 cm2 V−1 s−1 for PDMO‐S and 0.025 cm2 V−1 s−1 for PDMO‐Se . AFM and 2D‐GIXRD analyses demonstrated that the PDMO‐S formed lamellar, edge‐on packing thin film with close π‐π stacking. These findings suggest that cross‐conjugated polymers might be potential semiconducting materials for low‐cost and flexible organic electronics. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1012–1019 相似文献