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1.
Systematic research on the synthesis, chemical oxidative polymerization of 3,4‐ethylenedithiathiophene (EDTT) in the presence of surfactants or not, and solid‐state polymerization of 2,5‐dibromo‐3,4‐ethylenedithiathiophene (DBEDTT) and 2,5‐diiodo‐3,4‐ethylenedithiathiophene (DIEDTT) under solventless and oxidant‐free conditions has been investigated. Effects of oxidants (Fe3+ salts, persulfate salts, peroxides, and Ce4+ salts), solvents (H2O, CH3CN/H2O, and CH3CN), surfactants, and so forth on polymerization reactions and properties of poly(3,4‐ethylenedithiathiophene) (PEDTT) were discussed. Characterizations indicated that FeCl3 was more suitable oxidant for oxidative polymerization of EDTT, while CH3CN was a better solvent to form PEDTT powders with higher yields and electrical conductivities. Dispersing these powders in aqueous polystyrene sulfonic acid (PSSH) solution showed better stability and film‐forming property than sodium dodecylsulfate and sodium dodecyl benzene sulfonate. Oxidative polymerization of EDTT in aqueous PSSH solutions formed the solution processable PEDTT dispersions with good storing stability and film‐forming performance. Solvent treatment showed indistinctive effect on electrical conductivity of free‐standing PEDTT films. As‐formed PEDTT synthesized from solid‐state polymerization showed similar electrical conductivity, poorer stability, but better thermoelectric property than oxidative polymerization. Contrastingly, PEDTT synthesized from DIEDTT showed higher electrical conductivity (0.18 S cm?1) than DBEDTT which showed better thermoelectric property with higher power factor value (6.7 × 10?9 W m?1 K?2). © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

2.
[reaction: see text] We have developed a convenient and straightforward procedure for the preparation of functionalized 3,4-ethylenedioxythiophene (EDOT) systems by using a new chloromethyl-EDOT derivative as a versatile synthon. Based on this procedure, novel suitably functionalized perylenetetracarboxylic diimide (PDI) dye derivatives covalently linked to 3,4-ethylenedioxythiophene moieties have been synthesized and electrochemically polymerized to yield a donor-acceptor PEDOT derivative with an enhanced absorption cross-section.  相似文献   

3.
By employing planar thieno[3,2‐b]thiophene (TT) as end‐capped units and famous 3,4‐ethylenedioxythiophene (EDOT) or its all‐sulfur analog 3,4‐ethylenedithiathiophene (EDTT) as cores, two conjugated oligomer, TT‐EDOT‐TT and TT‐EDTT‐TT, have been synthesized and electropolymerized into electrochromic polymer films, P(TT‐EDOT‐TT) and P(TT‐EDTT‐TT), respectively. Due to strongly noncovalent inter/intramolecular interactions from S? S attraction of TT‐EDTT‐TT, it has twisted molecular configuration in contrast to planar TT‐EDOT‐TT. Spectroscopic, electrochemical, morphological as well as theoretical calculation studies of these oligomers or polymers were carried out to reveal the significant influence of such molecular geometry on their physicochemical and optoelectronic properties. According to electrochromic kinetics, P(TT‐EDTT‐TT) presented preferable electrochromic behavior such as the higher optical contrast (70.8%), favorable coloration efficiency (331.3 cm2 C?1) and fast response time (0.72 s). This research will help us deeply understand the effect of spatial organization of precursor molecules on the properties of electrochromic polymers and provides a promising strategy to develop high‐performance electrochromic materials. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1041–1048  相似文献   

4.
In this Letter we report the synthesis, characterization, and electrochemical investigation of a 3,4-ethylenedioxythiophene (EDOT) derivative covalently linked to the nucleobase uracil. The successful electrochemical polymerization of this derivative has provided modified electrodes with a novel functional poly(3,4-ethylenedioxythiophene) derivative. Recognition experiments in aqueous media have shown the specific recognition of the complementary base adenine. The electrochemical detection of the selective binding of nucleobases to this PEDOT derivative in aqueous media can be of particular interest for electrochemical sensor applications in physiological media.  相似文献   

5.
2-(Chloromethyl)-3,4-diphenylfuran reacted with aqueous potassium cyanide to give an α-angelica lactone derivative (V, 3,4-diphenyl-5-methyl-2(5H)furanone), which has never been isolated in such a reaction, as the main product.  相似文献   

6.
1,2,4-Triazole derivative substituted in the 4th position — 4-(3,4-dichlorphenyl)-1,2,4-tirazole — has been synthesized. Crystal and molecular structure of the compound were determined by single crystal X-ray diffraction. Molecular geometry optimization and effective charge calculations were performed by DFT methods.  相似文献   

7.
The titanium-mediated cyclopropanation reaction using Ti(OiPr)3Me/EtMgBr/BF3·OEt2 has been applied to various 2-cyanopyrrolidines for the synthesis of functionalized 2-(1-aminocyclopropyl)pyrrolidine-3,4-diol derivatives (dideoxyiminoalditols). Under the same experimental conditions the trans-5-azidomethyl-2-cyanopyrrolidine derivative was not cyclopropanated but reduced into the corresponding 5-amino-2-cyano derivative. After polyol deprotection 2-(1-aminocyclopropyl)pyrrolidine-3,4-diols were obtained and their inhibitory activity towards 13 glycosidases has been evaluated. (2S,3S,4R,5S)-2-(1-Aminocyclopropyl)-5-methylpyrrolidine-3,4-diol (38), which has the same absolute configuration as l-fucose, is a moderate (IC50=44 μM), but selective, inhibitor of α-l-fucosidase from human placenta.  相似文献   

8.
Heating the title compound with benzene provides a mixture of dimethyl 1,3-dihydroxynaphthalene-2,4-dicarboxylate and 3-carbomethoxy-4-hydroxy-5-phenylpyrone which rearranges on melting to the aforementioned naphthalene derivative. The initial substitution reaction appears to proceed through an intermediary pyronyl cation. The scope of this potential ring annelation reaction has been investigated for a range of aromatic and heteroaromatic compounds. Heating with basic substrates converts the bisdazo compound into dimethyl 4-hydroxypyrazole-3,5-dicarboxylate, while heating with isopropanol yields dimethyl 4,5-dihydroxypyridazine-3,6-dicarboxylate.  相似文献   

9.
A procedure has been developed for the determination of bisphenol A (BPA) in foods by gas chromatography/mass spectrometry as 2,2-bis-(4-(isopropoxycarbonyloxy)phenyl)propane formed in the reaction with isopropyl chloroformate. Optimal conditions have been found for BPA derivatization, providing its quantitative conversion into diether derivative in aqueous media. The concentration of BPA has been determined in some samples of canned foods and beverages (from 2.15 to 42.91 ng/g). The detection limit is 0.05–0.1 ng/g.  相似文献   

10.
A procedure has been developed for the direct fourth derivative spectrophotometric determination of zinc(II) dimethyldithiocarbamate by converting it into its copper(II) dimethyldithiocarbamate complex, which is then dissolved in Triton X-100. Beer's law is obeyed over the concentration range 0.5–30?µg/mL in the final solution. Various parameters such as the effect of pH and the interference of a number of ions on the determination of Ziram have been studied in detail. The method is sensitive and can be used for the determination of Ziram in commercial samples like Zirax and Ziron containing Ziram and from wheat grains.  相似文献   

11.
The Dieckmann condensation of 3,4-bis(methoxycarbonylmethyl) levoglucosenone derivative afforded two regioisomeric 9,11-dioxatricyclo[6.2.1.02,6]undecane derivatives at a ratio of 5: 3. The products can be used in the synthesis of iridoids.  相似文献   

12.
Exfoliated nanocomposites formed by poly(3,4-ethylenedioxythiophene) and different concentrations of non-modified montmorillonite (bentonite), which range from 1% to 10% w/w, have been prepared by anodic electropolymerization in aqueous solution. Analyses of the electrochemical and electrical properties reveal that the electroactivity of the nanocomposites is higher than that of the individual homopolymer, while the electrical conductivity of the two systems is practically identical. On the other hand, the exfoliated distribution of the clay in the polymeric matrix and the morphology of the prepared materials have been characterized using transmission electron microscopy, X-ray diffraction and atomic force microscopy. The overall of the results represents a significant improvement with respect to other nanocomposites constituted by conducting polymers and clays, including those involving poly(3,4-ethylenedioxythiophene), and evidences the reliability of the preparation procedure employed in this work.  相似文献   

13.
s-Triazolo[3,4-a]isoquinoline (II) and its 3-methyl analogue (III) have been synthesized from 1-isoquinolylhydrazine (I) by cyclisation with formic and acetic acid. The 3-hydroxy derivative (IV) has been shown to exist in the lactam form. Methylation with methyl iodide gave the N-methyl derivative (V). Dimethyl sulphate and diazomethane also led exclusively to the same product. The O-methyl derivative (IX) could be obtained only through the 3-chloro compound (VIII). The chlorine atom in VIII undergoes nucleophilic replacement easily. The 3,6-dichloro derivative (X) has also been prepared. Several interconversions in the series are described. Aryl hydrazones (XVIII) prepared from (I) have been oxidatively cyclised to give 3-aryl-s-triazolo[3,4-a]isoquinolines (XIX). U.V., I.R. and P.M.R. spectra have been recorded and used for assignment of structures in some cases.  相似文献   

14.
A simple procedure for the synthesis of substituted (E)-2-alkene-4-ynecarboxylic esters has been achieved using hydroxyapatite-supported palladium as efficient catalyst surface. The catalyst is recycled, and the turnover number (TON) based on Pd is 16000. A naphthyl-substituted derivative gives very intense fluorescence emission.  相似文献   

15.
A convenient procedure has been developed for the synthesis of 3,4-diaryl(or hetaryl)maleimides by cross coupling of N-substituted 3,4-dibromomaleimides with aryl(hetaryl)boronic acids in the presence of Pd(Ph3P)4 and CsF. The reaction ensures high yields of the products and requires relatively small amount of the catalyst; it can be performed on an enlarged scale. The resulting maleimides are readily converted into the corresponding maleic anhydrides.  相似文献   

16.
Russian Journal of General Chemistry - A two-step procedure has been proposed for the synthesis of 1,2-bis(2-oxocycloalkyl)ethane-1,2-diones and 3,4-dioxo-4-(2-oxocycloalkyl)butanoic acid esters by...  相似文献   

17.
A new chiral auxilliary, (S)-N-(2,4,6-trimethylbenzyl)proline (2-benzoylphenyl)amide, has been synthesised as a potential building block for the preparation of chiral synthons of amino acids. The nickel(II) complex of its Schiff base derivative with glycine has been methylated with 97% d.e. (diastereomeric excess), whilst the nickel(II) complex of its Schiff base derivative with (RS)alanine has been 13C-methylated with 66% d.e.  相似文献   

18.
TheDidemnaketalsAandBhavebeenreportedtobesignificantinhibitorstoHlV-protease'.Inconnectionwiththetotalsynthesisofthiskindofcompounds,ourrecentresearchinterestisfocusedontheirsyntheticstudiesaswellassynthesisofananaloguel,whichincorPoratedthekeyspiroketalmoietyofthedidemnaketalsAandB.Basedontheretrosyntheticconsideration(Schemcl),thelinearintermediate2wouIdbeconstructedfrom3and4.Furthermore,4wouldbesynthesizedfrom( )-PuIegone5.Wehereinreportedastereoselectivesyntheticprocedureforthe(3S,5S…  相似文献   

19.
Convenient and efficient syntheses of ethyl 4-(3-hydroxy-4-methoxyphenyl)-6,7-dimethoxy-2-(1,2,4-triazol-1-ylmethyl)quinoline-3-carboxylate (1d) and 10-(3,4-dimethoxyphenyl)-7,8-dimethoxy-2H-pyridazino[4,5-b]quinolin-1-one (1e), metabolites of TAK-603 (1), have been achieved. Use of the methanesulfonyl as a protective group of the phenolic hydroxy for Friedel-Crafts reaction enabled a new simpler synthetic route of 1d in high yield. Chloromethyl derivative (23) was converted to formyl derivative (32) using the Kröhnke reaction, followed by cyclization with hydrazine, which formed a novel compound 1e.  相似文献   

20.
WEN  Li-Rong WANG  Li-Juan LI  Ming 《结构化学》2011,30(6):867-871
The title compound(C25H16Cl2N3O3S),as a thiopyran derivative,has been synthe-sized by the cyclization of an organic intermediate obtained from Baylis-Hillman adducts with a β-aroylthioamide using copper(I) salt as the catalyst.The crystal belongs to the monoclinic system,space group P21/c with a = 13.668(3),b = 8.4803(17) c = 21.999(4) ,β = 113.57(3)°,V = 2337.2(10) 3,Z = 4,Mr = 510.38,Dc = 1.451 g/cm3,μ = 0.401 mm-1,F(000) = 1048,the final R = 0.0487 and wR = 0.1079 for 3678 observed reflections with I > 2σ(I).  相似文献   

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