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1.
Abstract

Mono(thio)substituted nitrodienes were synthesized by reactions of 2-nitro-pentachloro-1,3-butadiene with some thiols [(tert-butylbenzyl)thio- and 2,3,5,6-tetra-fluorophenylthio-] either directly or in ethanol in the presence of sodium hydroxide. N,S-Substituted 1,3-butadienes were obtained from the reaction of the mono(thio)substituted nitrodienes with morpholine and some piperazine derivatives in dichloromethane. Also mono- and di(thio)substituted perchlorobutadienes were synthesized from the reactions of hexachloro-1,3-butadiene with o-aminothiophenol in ethanol in the presence of sodium hydroxide. The structures of the new compounds were characterized by microanalysis and spectroscopic data.  相似文献   

2.

The phase behavior of dodecyltrimethylammonium bromide (DTAB)/sodium dodecyl sulfonate (AS)/H2O system in the presence and in the absence of sodium phosphate has been studied. Two kinds of aqueous two‐phase systems (ATPSs) were formed, one is ATPS‐A in which anionic surfactant is in excess, the other is ATPS‐C in which cationic surfactant is in excess. For the CTAB/AS/H2O system, the addition of sodium phosphate changes the extraction phenomena of both ATPS‐A and ATPS‐C. For the DTAB/AS/H2O system, the addition of sodium phosphate changes the extraction phenomena of ATPS‐C. For ATPS‐C, the addition of trivalent PO4 3? results in a strong extraction effect of ATPS‐C to cationic water‐soluble dye methylene blue.  相似文献   

3.
《合成通讯》2013,43(15):2829-2833
Abstract

The reaction of electron‐rich arenes with alkali metal iodides such as sodium and potassium iodides in the presence of conc. H2SO4 gives p‐iodoarenes in high yields.  相似文献   

4.
Abstract

Molecular recognition behavior of eight cyclodextrin derivatives, i.e. mono(6-pyridinio-6-deoxy)-α-cyclodextrin (1α), mono(6-pyridinio-6-deoxy)-β-cyclodetrin (1β), mono(6-pyridinio-6-deoxy)-γ-cyclodextrin (1γ), mono[6-(p-picolinio)-6-deoxy]-β-cyclodextrin (2β), mono(6-anilino-6-deoxy)-β-cyclodextrin (3β), mono[6-(m-toluidino)-6-deoxy]-β-cyclodextrin (4β), mono[6-O-(8-quinolyl)]-β-cyclodextrin (5β), and novel mono[6-(2-naphthylamino)-6-deoxy]-β-cyclodextrin (6β), with a series of aliphatic alcohols and carboxylic acid has been investigated spectroscopically. Using the appended aromatic group as a spectral probe, spectroflurometric or spectropolarimetric titrations have been performed at 25°C in aqueous phosphate buffer solution (pH 7.20, 0.1 M) to determine the complex stability constants (Ks ) and Gibbs free energy changes (-δG°) for the stoichiometric 1:1 inclusion complexation of cyclodextrin derivatives with the guests. The results obtained demonstrate that the modified cyclodextrins are highly sensitive to the size/shape and hydrophobicity of guest molecules, and particularly 5β gives an excellent molecular selectivity up to 215 for 1-adamantanol/cyclohexanol. The binding ability and selectivity of the modified cyclodextrins (1α, 1β, and 1β-6β) are discussed from the view points of size/shape-fit concept, induced-fit interaction, and the multiple recognition mechanisms.  相似文献   

5.
Abstract

The disodium O-alkylthiophosphates were synthesized by reaction of PSCl3 with the corresponding alcohols to the O-alkylphosphorodichloridothioates (1), which were hydrolyzed in aqueous triethylamin–sodium acetate solution.1 The O-alkylthiophosphates (2) were isolated as barium salts and converted to the disodium salts by Na2SO4.

Because the barium salts of O-ethyl- and O-n-propyl-thiophosphate were soluble in water, the corresponding dichlorido compounds were hydrolyzed directly to the disodium salts in aqueous sodium hydroxide plus dioxane according to Gray and Hamer.2

Further purification was achieved by column chromatography on Sephadex LH20 using water as an eluant. Pure products, which were not contaminated by either inorganic thiophosphate or O-alkylphosphates, were thus obtained.  相似文献   

6.
Abstract— In order to study energy transfer to zinc tetraphenylporphyrin (ZnTPP) in micellar solution, a series of surface active agents of sodium N-alkyl carbazole sulfonate, were synthesized. The energy transfer efficiency from the carbazole group near the surface to ZnTPP located in the core of sodium lauryl sulfate (NaLS) micelles was found to be 30%, as observed through the fluorescence of ZnTPP. The critical micelle concentrations (CMC) of the sodium N-alkyl carbazole sulfonate surfactants, determined by scattering, were 2 times 10-4 M, 3 times 10-5M and 3 times 10-6 M, respectively, for alkyl: octyl, dodecyl and hexadecyl. The sensitivity of the CMC of NaLS to the presence of foreign surfactants and solubilizates was also investigated.  相似文献   

7.

Using the gel synthesis approach of polymer-analogous transformations, N-sulfoethylation of polyethylenimine was carried out by treating the polymer with sodium vinyl sulfonate. The compositions and structures of the products were characterized by elemental analysis, FT-IR spectroscopy, and 1H NMR spectroscopy. At pH 3.0–4.5 sulfoethylated polyethylenimine can selectively extract AgI and CuII from an ammonia—acetate buffer solution in the presence of a series of transition and alkaline-earth metals. At pH > 6.5 the sorbent can be used for the group extraction of a number of transition metal ions. The structural feature of the obtained derivative eliminates the selectivity of sorption of AgI ions compared to CuII ions, which has previously been revealed for the sulfoethylated derivatives of chitosan and polyaminostyrene.

  相似文献   

8.
This paper reports on a facile method for synthesizing gold nanoparticles (AuNps) with diameter around 5 nm encapsulated with water‐soluble polythiophene sulfonate poly[2‐(3‐thienyl)ethyloxy‐4‐butylsulfonate] sodium salt (PTS) and their physical–chemical characterization. The synthesis of hybrid materials of polythiophene derivatives and gold nanoparticles is a way to improve the polymer properties, mainly in application for chemical and optical sensing platforms. The AuNps were prepared by reducing gold salt with acid aqueous sodium citrate by the Turkvich method in the presence of PTS, and both PTS and citrate helped to stabilize the AuNps. The suspensions of AuNp:PTS presented good chemical and photostability for long period of storage. The nanoparticles encapsulated with the polymer presented smaller diameters than those obtained using only sodium citrate, according to scanning electron microscopy images. The AuNps obtained were used for fabrication LbL films with commercial chitosan, which were characterized by impedance spectroscopy measurements. The results showed that the charge transfer resistance values (Rct) decrease as the average diameter of the AuNps decreases and the proportion of PTS increases in the nanocomposite. Such increase of the nanocomposite conductivity, given by the low values of Rct, indicates that the novel film architecture developed is promising for chemical sensing applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1245–1254  相似文献   

9.
The mono‐filaments (> 10 m in length) of chitosan and the blends of chitosan‐collagen, chitin‐collagen and chitin‐silk fibroin were wet‐spun. The mono‐filaments were chemically N‐modified with each of n‐fatty acid anhydrides, intra‐molecular carboxylic anhydrides, fragrant aldehydes and transition metal ions. The mono‐filament was aligned on a straight line with the mono‐filament of silk fibroin or poly(ethylene terephthalate) (PET), and a bundle of one to three mono‐filaments was coated with a medium of sericin (Se), chitosan or N‐acylchitosan to give rise to novel silk‐mimic filament composites. The filaments coated with a medium of sericin exhibited 26–27 denier for the titer, 2.46–3.36 gf · denier?1 for the tenacity and 11.8–25.0% for the elongation. The apparent density (denier · μm?1 in the filament diameter) of the filament composites was about 3–4 times higher than that of the mono‐filaments. Portion of fragrant aldehydes in Schiff's base was slowly hydrolyzed at room temperature by contacting with atmospheric moisture in the open air, and released from the fragrant filaments and composites. The filament composites coated with a chitosan medium were thrombogenic, and those coated with N‐acylchitosans were antithrombogenic.

An illustrated model for a silk‐mimic filament composite, N0(N2I‐FI).  相似文献   


10.
Summary The interaction of sodium decane sulfonate and sodium dodecyl sulfate with sodium and calcium montmorillonite was investigated byx-ray diffraction. Sorption of detergent by clay was calculated from the decrease in detergent concentration and from carbon analysis of the solids.The two detergents did not interact with sodium montmorillonite either below or above their critical micelle concentrations. Calcium montmorillonite sorbed both detergents, but metathesis, leading to the precipitation of some calcium alkyl sulfate and sulfonate, and hydrolysis of dodecyl sulfate complicated the situation.Thex-ray patterns of calcium montmorillonite treated with detergent solutions and dried contained two sets of (00l) reflections. One, rather broad, belonged to unmodified clay. Like untreated dry clay, its basal spacing increased by 6 Å on exposure to 85% relative humidity, owing to insertion of two monolayers of water between adjacent clay lamellae. The other set consisted of narrow reflections; their basal spacing, which did not increase on exposure to 85% relative humidity, exceeded that of unmodified clay by a distance equal to the extended length of the C10H21SO3- and C12H25OSO3-anions, respectively. Therefore, the sorbed, intercalated detergent molecules were fully extended, with their chain axis perpendicular to the plane of the clay lamellae.Sorption may have occurred in two steps: (1) binding of alkyl sulfonate and sulfate anions by calcium counterions of the clay, followed by (2) sorption of sodium alkyl sulfonate and sulfate molecules by association between their hydrocarbon tails and those of previously sorbed detergent anions throughvan der Waals forces.
Zusammenfassung Die Aufnahme von Natriumdecylsulfonat und Natriumdodecylsulfat in Natrium- und Calcium-Montmorillonit wurde durch Analyse der Gleichgewichtslösungen und der Bodenkörper untersucht. Aus röntgenographisch bestimmten Schichtabständen wurde auf die Anordnung der Detergentienmoleküle im Schichtzwischenraum geschlossen.


With 5 tables  相似文献   

11.

Reported is the first method to prepare a new class of thienopyrazole thioglycosides via a one‐pot reaction of the sodium thienopyrazolthiolate salts with 2,3,4,6‐tetra‐O‐acetyl‐α‐D‐gluco‐and galactopyranosyl bromides. The sodium thienopyrazolthiolate salts are prepared using pyrazoldithioic acids and their corresponding mono ‐ and dithiolate salts.  相似文献   

12.
A range of novel water-soluble alkylated ferrocene sulfonate compounds are reported. Mono- and di-sulfonation on a series of alkyl ferrocenes produced 1,1′-dimethyl ferrocene sulfonate, 1,1′-dimethyl ferrocene disulfonate, 1,1′-diethyl ferrocene sulfonate, 1,1′-diethyl ferrocene disulfonate, t-butyl ferrocene sulfonate, t-butyl ferrocene disulfonate, ethyl ferrocene sulfonate, ethyl ferrocene disulfonate, n-butyl ferrocene sulfonate and n-butyl ferrocene disulfonate. All compounds were characterized by NMR spectroscopy, UV/Vis spectroscopy and electrochemical analysis. 1H and 13C NMR studies have revealed the formation of several isomers with sulfonation occurring on positions α and β to the alkyl substituent or on the unsubstituted cyclopentadienyl ring. Variation of the alkyl group allowed the isomeric pattern to be tuned such that the final products followed either electronic or steric control. Cyclic voltammetry of the resulting products showed that the redox potential of the iron centre can be easily manipulated by changing the substituents on the cyclopentadienyl rings. This result has significant implications in the future development of homogenous redox mediators for sensing applications.  相似文献   

13.
《Analytical letters》2012,45(4):661-676
Abstract

A novel amperometric sensor of hydrogen peroxide was constructed. Hemoglobin (Hb) was successfully immobilized on nanometer‐sized SiO2, which was supported by chitosan. Chitosan was acted as dispersant. The determination of hydrogen peroxide was performed in the presence of an electron mediator hydroquinone. Hb immobilized on the SiO2/chitosan composite film displayed excellent electrocatalytical activity to the reduction of H2O2. The linear range of detection towards H2O2 was from 6.25×10?7 to 1.63×10?4mol/L with a detection limit of 1.8×10?7mol/L (S/N=3). The apparent Michaelis‐Menten constant (K app M) was found to be 0.75mmol/L.  相似文献   

14.

Mono(thio)substituted dienes 1 gave 3a–g , 5 , and 7 with piperazine derivatives in dichloromethane. Hexachlorobutadiene 14 in a water-ethanol mixture in the presence of sodium hydroxide reacted with thiol 15 to give the mono(thio)substituted thioether 16 and di(thio)substituted thioether 17 . 18 was obtained from the reaction of 16 with m-CPBA in chloroform. 9 was obtained from the reaction of l,2,3,4,4-pentachloro-(1-2-hydroxyethylthio)-1,3- butadiene 8 with 47% HI, and 11 was synthesized from the reaction of 8 with concentrated H2SO4 and KBr. Compounds 9 and 11 gave in the reaction with m-CPBA in chloroform 10 , 12 , and 13 , respectively.  相似文献   

15.
Sulfonated poly(phthalazinone ether ketone) (SPPEK) copolymers and sulfonated poly(phthalazinone ether sulfone) (SPPES) copolymers containing pendant sodium sulfonate groups were prepared by direct copolymerization. The reaction of disodium 3,3′‐disulfonate‐4,4′‐difluorobenzophenone (SDFB‐Na), 4,4′‐difluorobenzophenone (DFB), and 4‐(4‐hydroxyphenyl)‐1(2H)‐phthalazinone (DHPZ) at 170 °C in N‐methyl‐2‐pyrrolidione containing anhydrous potassium carbonate gave SPPEKs. SPPESs were similarly obtained with 3,3′‐disulfonate‐4,4′‐difluorophenyl sulfone, 4‐fluorophenyl sulfone (DFS), and DHPZ as monomers. The sulfonic acid groups, being on deactivated positions of the polymer backbone, were expected to be hydrolytically more stable than postsulfonated polymers. Fourier transform infrared and 1H NMR were used to characterize the structures and degrees of sulfonation of the sulfonated polymers. Membrane films of SPPEKs with SDFB‐Na/DFB molar feed ratios of up to 60/40 and SPPESs with sulfonated 4‐fluorophenyl sulfone/DFS molar feed ratios of up to 50/50 were cast from N,N‐dimethylacetamide polymer solutions. Membrane films in acid form were then obtained by the treatment of the sodium‐form membrane films in 2 N sulfuric acid at room temperature. An increase in the number of sulfonate groups in the copolymers resulted in an increased glass‐transition temperature and enhanced membrane hydrophilicity. The sodium‐form copolymers were thermally more stable than their acid forms. The proton conductivities of the acid‐form copolymers with sulfonated monomer/unsulfonated monomer molar feed ratios of 0.5 and 0.6 were higher than 10?2 S/cm and increased with temperature; they were less temperature‐dependent than those of the postsulfonated products. SPPESH‐50 showed higher conductivity than the corresponding postsulfonated poly(phthalazinone ether sulfone). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2731–2742, 2003  相似文献   

16.
《合成通讯》2013,43(6):999-1004
Abstract

Efficient and regioselective conversion of epoxiodes to vicinal azidoalcohols with sodium azide in wet t-butanol and in the presence of catalytic amount of lithium tetrafluoroborate, LiBF4 in excellent yields under mild reaction conditions is described.  相似文献   

17.
Since few examples of 10,11‐didehydrogenated (3‐ethynyl) cinchona alkaloids have been utilized as organocatalysts in asymmetric reaction, we synthesized 10,11‐didehydrogenated cinchonidine. The 3‐vinyl group of cinchonidine was transformed into a 3‐ethynyl functionality. Based on the resulting 10,11‐didehydrogenated cinchonidine, the corresponding quaternary ammonium salt and its dimers were prepared. The ion‐exchange reaction between the quaternary ammonium salt and sodium sulfonate produced the quaternary ammonium sulfonate as a stable ionic compound. Chiral ionic polymers were then synthesized by the ion‐exchange polymerization of the 10,11‐didehydrogenated cinchonidinium salt dimer and a disulfonate. The chiral ionic polymers were found to be capable of efficiently catalyzing the asymmetric alkylation of N‐(diphenylmethylene)glycine tert‐butyl ester. The enantioselectivities obtained with the polymeric catalysts were higher than those obtained with the corresponding monomeric catalyst. Dimers of 10,11‐didehydrogenated cinchonidinium salts were prepared. Treatment of the dimer with disodium disulfonate gave the chiral ionic polymers, which showed high catalytic activity in asymmetric benzylation of N‐(diphenylmethylen)glycine tert‐butyl ester. The polymeric catalysts were reused several times without the loss of catalytic activity. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 621–627  相似文献   

18.

The combination of iminodiacetic acid (H2ida) with cobalt(II) chloride hexahydrate in the presence of sodium hydroxide, followed by heating, produces the trans-facial isomer of K[Co(ida)2]·2H2O. This compound contains extensive intermolecular and intramolecular coordination and hydrogen bonding involving the potassium ions, and results in a complex three-dimensional structure in which each potassium ion is immediately surrounded by six cobalt centers.  相似文献   

19.
Abstract

New mono, bis and polyspirophosphoranes have been prepared condensing alditols with aminophosphines P(NR2)3.  相似文献   

20.

In this study, the sulfidization of Na2CO3 was investigated by using a solid-gas reaction under a sulfidizing gas mixture, which consisted of COS, CS2, and S2 gases.

Sodium sulfide pentahydrate, Na2S·5H2O, was prepared from sodium carbonate, Na2CO3, via a sulfidizing gas mixture by a solid-gas reaction under the cooling of a nitrogen atmosphere. The observed phase was found to be the pentahydrated form of sodium sulfide. This crystalline form was determined by X-ray powder diffraction (XRD) technique. Since sodium sulfide is strongly hygroscopic, the pentahydrated crystalline form was observed in XRD measurements for all repeated experiments. The crystal unit cell parameters of the synthesized product were in excellent agreement with values given in the JCPDS card number 18-1249. The sodium sulfide pentahydrate has an orthorhombic crystal structure with the unit cell parameters of a = 6.475, b = 12.55, C = 8.655 Å, space group, Cmcm and Z = 4.  相似文献   

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