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1.
Abstract

Inorganic phosphates were chromatographed on a Sephadex G-25 column using lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride and tetramethylammonium chloride as an eluting agent at pH 10. When tetramethylammonium chloride was used the distribution coefficient of a linear phosphate was apparently smaller than that of the cyclic phosphate which has the same number of phosphorus atoms in its molecule. It was concluded that gel chromatographic behavior of phosphate species is greatly influenced by the nature of counter ions in an eluent.  相似文献   

2.
In the present investigation new baths have been adopted for the anodic deposition of different nickel oxides. The deposition of the different oxides was carried out from their metal salt solutions in the presence of a complexing agent. The following oxides were obtained: NiO2 from nickel chloride in the presence of ammonium chloride and sodium fluoride; Ni2O3 from nickel sulphate in the presence of ammonium chloride and citric acid; Ni3O4 from nickel chloride in the presence of sodium hydroxide, formaldehyde and potassium chloride, and finally NiO from nickel chloride in the presence of sodium carbonate, sodium chloride and ethanol.  相似文献   

3.
The arylation of carbonylgold chloride with diarylzinc compounds yields either triarylgoldzinc or diarylgoldzinc chlorides, depending on the reactant ratio and the nature of the aryl group. The same reactions with diphenylcadmium and diphenylmercury yield exclusively diphenylgoldcadmium chloride and diphenylgoldmercury chloride, respectively. The reactions of the products with N,N,N′,N′-tetramethylethylenediamine and triphenylphosphine were studied.Phenylgold has been obtained as a very unstable solid from diphenylgoldzinc chloride and diphenylgoldmercury chloride.  相似文献   

4.
Phosphoryl chloride reacts with 2-picoline-N-oxide in the presence of triethylamine to give 2-chloromethylpyridine in 90% conversion with 98% selectivity. Diethylchlorophosphate, ethyl chloroformate, chloroacetyl chloride and phosgene also react with 2-picoline-N-oxide to give 2-chloromethylpyridine in moderate yields. Other potential chlorinating agents, titanium tetrachloride, zinc chloride, magnesium chloride and sulfuryl chloride, did not convert 2-picoline N-oxide into 2-chloromethylpyridine.  相似文献   

5.
Vinyl chloride and vinylidene chloride were copolymerized with 10-acryloxydecanoyl chloride and 12-acryloxystearoyl chloride by use of free-radical initiator in solution to obtain copolymers with active chlorine groups. Alternative routes for making such copolymers which consisted of making the corresponding acrylic acid or acrylyl chloride copolymers, followed by reaction with hydroxy acid and finally conversion to the acid chloride by treatment with thionyl chloride, were investigated. The monomer reactivity ratios for the radical copolymerization of vinyl chloride (VCI) and vinylidene chloride (VCl2) with acrylic acid (AA) and acrylyl chloride (ACI) were determined: VCI–AA, r1 = 0.025, r2 = 6.40; VCl–ACl, r1 = 0.017, r2 = 2.65; VCl2–AA, r1 = 0.46, r2 = 1.26; VCl–ACl, r1 = 0.50, r2 = 1.12.  相似文献   

6.
A manual method for the determination of hydrogen chloride in air, based on diffusion/denuder tube separation from particulate chloride aerosol is described. When air is drawn through a tube coated with a selective absorbent (sodium fluoride), separation is achieved because gaseous hydrogen chloride diffuses much more rapidly to the tube walls than particulate chloride aerosol, which passes through virtually unabsorbed. After the sampling period (the length of which depends on the concentration of gaseous hydrogen chloride expected), the sorbed hydrogen chloride is washed from the tube and measured with a highly sensitive chloride ion-selective electrode with a mercury (I) chloride membrane. The method is examined theoretically and experimentally. The experimentally derived absorption efficiencies of the diffusion/denuder tubes were > 90% and the standard deviation of the method was 0.023 μg m?3 for hydrogen chloride concentrations of 0.16–0.55 μg m?3. Interference from particulate chloride salts was negligible; this was confirmed by tests with artificially generated aerosol particles from an aerosol generator. The diffusion/denuder tubes have high capacity; level as high as 330 μg m?3 hydrogen chloride can be sampled for 60 min without affecting performance. A detection limit of (50/t) μg m?3 can be achieved, where t is the sampling rime (min); e.g., 1μg m?3 hydrogen chloride can be detected with a sampling period of 50 min.  相似文献   

7.
A new series of chiral macrocyclic polyether-diester ligands has been prepared from four chiral dimethyl substituted tetraethylene glycols ( 15a,b,16,17 ) and 2,6-pyridinedicarbonyl chloride (products 5a-7 ), diglycolyl chloride (products 8–10 ), thiadiglycolyl chloride (product 11 ), 2,5-furandicarbonyl chloride (product 12 ), 4-chloro-2,6-pyridinedicarbonyl chloride (product 13 ), and 4-methoxy-2,6-pyridinedicarbonyl chloride (product 14 ). The chiral dimethyl substituted tetraethylene glycols ( 15a-17 ) were prepared from ethyl (S)-lactate.  相似文献   

8.
Summary A continuous flow analysis is described for the determination of total mercury by cold vapor atomic absorption spectrometry. Organic mercury compounds such as methylmercury(II) chloride, ethylmercury(II) chloride and phenylmercury(II) chloride were decomposed by potassium peroxodisulphate with addition of ferric chloride as catalytic reagent. The reducing reagent used was tin(II) chloride in sodium hydroxide solution. With 1,000 mg Fe/l added in the decomposition process, we found that methylmercury(II) chloride and ethylmercury(II) chloride gave response signals similar to those of mercury(II) chloride. The proposed method was applied to the analysis of total mercury in waste water. Permanent address: Department of Chemistry, Faculty of Mathematics and Natural Sciences, Andalas University, Padang, West Sumatra, Indonesia  相似文献   

9.
R. Fuks  M. Hartemink 《Tetrahedron》1973,29(2):296-299
Alkylation of cyanogen chloride with alkyl chloride and ferric chloride gives an alkyl isocyanide dichloride-FeCl3 complex 2. Such novel complexes react either with water to give alkylamines, or with alcohol or alcoholate to give the corresponding N-substituted carbamate, or are converted to alkyl isocyanates with various reagents. Cyanogen chloride, isopropyl chloride and ferric chloride give complex 2a which, with zinc oxide, gives isopropylisocyanate. Salts of caiboxylic acids also furnished the isocyanate in good yield. The t-butylisocyanide dichloride-FeCI3 complex 2b does not react with zinc oxide but was transformed into f-butylisocyanate with trifluoroacetic acid or dimethyl sulphoxide.  相似文献   

10.
Changes in growth and fatty acid content ofSpirulina platensis were examined after transferring cells into media containing various concentrations of ammonium chloride. Photosynthetic O2 evolution rate decreased with increasing ammonium chloride concentration. Therefore, the algal growth was interrupted by ammonium chloride addition. On the other hand, total fatty acid content markedly increased after addition of ammonium chloride to a concentration of 15–50 mM and was maximized 40–48 h after addition of 25 mM ammonium chloride. The increases in palmitic and oleic acid content were especially remarkable. However, this began to decrease 48 h after the addition of 25 mM of ammonium chloride. Also, γ-linolenic acid content increased continuously during a 72-h incubation. As a result,Spirulina platensis cells containing about 2% γ-linolenic acid were obtained by ammonium chloride treatment, representing an increase of 1.5–2-fold compared to untreated cells.  相似文献   

11.
Voltammetric techniques were employed to study the electrochemical behavior of several anthocyanins. The redox behavior of anthocyanins with the same basic structure, the influence of glycosylation on the redox behavior of anthocyanins derived from different anthocyanidins, and the influence of methoxylation were investigated. The anthocyanins used in this study were malvidin‐3‐O‐glucoside chloride, malvidin‐3,5‐di‐O‐glucoside chloride, cyanidin‐3‐O‐glucoside chloride, cyanidin‐3,5‐di‐O‐glucoside chloride, peonidin‐3‐O‐glucoside chloride, delphinidin‐3‐O‐glucoside chloride and the anthocyanidin petunidin chloride, all of them present in Vitis vinifera L. All hydroxyl groups of the anthocyanins can be electrochemically oxidized and the anthocyanins studied revealed a complex and pH dependent oxidation process, with the occurrence of adsorption and of oxidation products blocking the electrode surface.  相似文献   

12.
The proton transfer from carbon to a chloride ion and the proton transfer to a molecule of water promoted by chloride ions in the acid-catalyzed formation of hydroxamic acids from aldehydes and substituted nitrosobenzenes in mixed solvents have been proposed based on experimental and theoretical investigations. The formation of uncommon contact ion pairs consisting of the nitrosocarbinolic cation intermediate and a chloride anion, followed by the proton transfer from a C-H moiety of the cation intermediate, has been proposed. The influence of chloride on the proton transfer to a water molecule of the solvent-separated nitrosocarbinolic-cation–chloride ion pair was investigated too. The insights are based on the obtained kinetic and other evidence with regard to (1) influences of chloride anions on the observed reaction rates and primary kinetic isotope effects (PKIE) in the reaction; (2) the observed variation of the PKIE-s and rates of the reaction when perchlorate anions are present along with the chloride ions; and (3) the consideration of a model of the nitrosocarbinolic-cation-intermediate—chloride ion pair and transition structure for the proposed proton transfers based on the ab initio calculations.  相似文献   

13.
《Vibrational Spectroscopy》2007,43(1):210-216
Triphenylmethyl chloride (“trityl chloride”, Ph3CCl) will transfer chloride ions to aluminium alkyls and methylaluminoxane and it is thereby converted into 1,1,1-triphenylethane (“trityl methyl” Ph3CMe) and the triphenylcarbonium ion (“trityl ion”, Ph3C+). IR spectra of these trityl species have been recorded. Assignments are supported by quantum chemical calculations, leading to significant revisions for some of the modes that are most influenced by reactions. A bright yellow colour shown to be due to the trityl cation, makes trityl chloride a useful indicator for ion pair formation. Trimethyl aluminium (TMA) is chlorinated by trityl chloride and forms dimethyl aluminium chloride (DMAC). DMAC will form a stable ion pair with trityl chloride, probably by forming the anion Al2Cl3Me4. Large excess of trityl chloride causes the formation of AlCl4, and probably AlCl3Me and AlCl2Me2 anions. It appears that methyl aluminium chloride anions are formed if, and only if, the anions have at least three chlorine atoms, possibly because of the need to dissipate the negative charge enough to keep the anion dissolved in the hydrocarbon solvent. Methylaluminoxane (MAO) also forms ion pair with trityl chloride, although to lesser extent and less persistent.  相似文献   

14.
The electrochemiluminescence (ECL) of luminol in aqueous alkaline solution was studied.Trace amounts of chloride showed significant effect on the efficiency of light emission of luminol as a posi-tive trigonometrical wave pulse was exerted on the solution. The detection limit for the chloride is5.0 ×10~(-6) mol/L and the linear calibration range extends up to 1.0 ×10~(-2) mol/L; the relative standarddeviation for 1.0 ×10~(-5) mol / L chloride is 5%. The influencing factors for chloride determination arealso discussed. The possible mechanism for the electrochemiluminescence reaction may be due to theoxidation of chloride ion in the solution to ClO~-, and the latter acts on luminol and then gives outluminescence. The method has been applied to determine the total chloride in tap water with satisfactoryresults.  相似文献   

15.
Intramolecular cyclization of 2-(allylthio)propionyl chloride ( 3a ) effected by aluminum chloride gave two dihydrothiopyran-3-ones ( 5a,6a ) and 5-chloro-2-methyltetrahydrothiopyran-3-one ( 7a ). Treatment of propargylthioacetyl chloride ( 4a ) with aluminum chloride afforded 5-chloro-3,6-dihydro-2H-thiopyran-3-one ( 10a ). The cyclization reactions of related compounds were also studied.  相似文献   

16.
Reactions of arc-generated carbon atoms with acyl chlorides proceed by two distinct mechanistic pathways depending on the nature of the alkyl group in the substrate. Acetyl chloride affords vinyl chloride from the putative chloromethylcarbene produced by deoxygenation, whereas pivaloyl chloride gives t-butyl chloride as the predominant product via a chain reaction from the initially generated pivaloyl radical. When the alkyl group is isopropyl, both pathways are implicated.  相似文献   

17.
Chlorobenzene and toluene were polymerized with aluminum chloride–cupric chloride to produce materials that consist mainly of poly(o-phenylene) structures. These species exhibited radical cation concentrations comparable to that of poly(p-phenylene). Polymerization of naphthalene and 1-chloronaphthalene with aluminum chloride–cupric chloride or ferric chloride–water also resulted in products with high radical cation concentrations. Polynuclear structures may be responsible for the paramagnetic character; alternatively, p-quinoidal moieties may be present in naphthalenes. The depth of color in the samples is directly related to the concentration of radical cations.  相似文献   

18.
G. Signore 《Tetrahedron》2008,64(49):11218-11223
This paper describes efficient and new approaches to (E) alk-1-enyl sulfones, starting from sulfonyl chloride/pyridine or sulfonyl chloride/triphenylphosphine complexes in the presence of (E) di-iso-butyl alk-1-enyl alanes.The use of CuCl in the presence of sulfonyl chloride/pyridine complexes or pyridine in the presence of sulfonyl chloride/triphenylphosphine complexes, respectively, results in a remarkable increase in the yields and conversions.  相似文献   

19.
Hexachlorocylotriphosphazene (1) was reacted with 4-hydroxy-3-methoxybenzaldehyde to give hexakis[(4-formyl-2-methoxy)phenoxy]cyclotriphosphazene (2). Hexakis[(4-(hydroxyimino)2-methoxy)phenoxy]cyclotriphosphazene (3) was synthesized by reaction of 2 with hydroxlamine hydrochloride in pyridine. Compound 3 was reacted with benzyl chloride, acetyl chloride, allyl bromide, benzoyl chloride, propanoyl chloride, 4-methoxybenzoyl chloride, 2-chlorobenzoyl chloride, chloroacetyl chloride, methyl iodide, and thiophene-2-carbonyl chloride. From these reactions, full or partially substituted compounds were obtained, usually in high yields. Pure or defined products could not be obtained from reaction of 3 with methacryloyl chloride and O-acetylsalicyloyl chloride. The structures of the compounds were determined by elemental analysis, and IR, 1H, 13C, and 31P NMR spectroscopy. The synthesized compounds were screened for in-vitro antimicrobial activity against two Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis), two gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), and fungal strains (Aspergillus niger, and Candida albicans) by the agar well diffusion method. Few compounds had significant activity against both Gram-positive and Gram-negative bacteria. None of the compounds had antifungal activity except compounds 7 and 9, which had moderate activity.  相似文献   

20.
3-Aminotropolone ( 1 ) reacted with acetyl chloride and propionyl chloride to give 2-methyl- and 2-ethyl-8H-cyclohept[d]oxazol-8-ones ( 2a and 2b ), respectively. The reactions with benzoyl chloride and phenylacetyl chloride gave N-acylated and N,O-diacylated 3-aminotropolones [(3a and 3b ) and ( 4a and 4b)] .  相似文献   

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