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1.
The effect of anionic surfactant (sodium dodecyl sulphate) and nonionic surfactant (Brij-35) on the hydrolysis of di-2-methoxy-4-nitroaniline phosphate was studied spectrophotometrically at 303 K. The influence of salts on the reaction rate was studied. The presence of inorganic salts (KCl, KNO3, and K2SO4) exhibited positive effect on the reaction rate. The thermodynamic activation parameters were calculated from Arrhenius equation. On the basis of the experimental findings a suitable mechanism has been proposed. The binding constants between the reactants and the surfactants evaluated from the kinetic models proposed by Menger-Portnoy, Piszkiewicz, and Berezin have been found in good agreement.  相似文献   

2.
Reactions of 2- and 3-nitro anilines (2- and 3-NA) with eaq, H-atoms and one-electron reductants have been studied using pulse radiolysis in aqueous solutions. Reactions of eaq were found to be quite fast with both 2-NA and 3-NA resulting in their corresponding semi-reduced species which are reducing in nature. Reduction potentials for 2-NA/2-Na•′ have been estimated to be approx. −0.56 Vvs. NHE and that for 3-NA/3-NA•− was found to be between −0.185 V and −0.45 Vvs. NHE. Semi-reduced 2-NA has main absorption peak at 300 nm with a shoulder in the 350 nm region and a broad weak band in the 470–500 nm region, whereas semi-reduced 3-NA possesses an absorption peak at 520 nm. Reducing radicals such as (CH3)2 COH and CO2•− reacted with 2-NA, producing semi-reduced species, whereas reactions of these radicals with 3-NA produced their corresponding radical-adduct species.  相似文献   

3.
This article reports the reactions of salts of 4‐ureylmethylpyridinium and 4‐ethoxycarbonylaminomethylpyridinium with carbonylic compounds, performed with the aim of obtaining new vinylpyridinium salts. These reactions can lead to the formation of both condensation and dimerization products. The type of products formed is conditioned by the nature of the salts and carbonyl groups involved. The interest generated by the condensation products formed lies in their potential cholinergic activity. J. Heterocyclic Chem., 2011.  相似文献   

4.
熔融盐对印刷线路板热解影响实验研究   总被引:6,自引:2,他引:4  
在固定床反应器中进行热解实验,考察不同热解终温、不同熔融盐添加量下印刷线路板热解过程中碳的气相转化率,并对热解液体和固体产物进行特性分析。结果表明,熔融盐的存在可以明显提高热解过程碳的气相转化率,减少液体产物产率。在未添加熔融盐的条件下,热解终温900℃时,碳的气相转化率为35.94%,液体产物产率为28.29%。添加 (71%Na2CO3-29%K2CO3) 熔融盐后,热解终温700℃时,碳的气相转化率为40.76%,液体产物产率为22.34%。添加 (8.3%Na2CO3-91.7%NaOH) 熔融盐后,碳的气相转化率达到59.36%,液体产物产率减少为6.88%。元素分析结果表明,熔融盐的存在可以减少固体残渣中的含碳量,而液体产物的H/C原子比为1.12~1.20。  相似文献   

5.
Cathodic reduction of diazonium salts in acetonitrile led to the formation of azobenzenes, in good to moderate yields, and diarylamines as minoritary products. The reactions were carried out at the second reduction potential of the diazonium salts, involving aryl anions in the formation of the products.  相似文献   

6.
Erdey L  Simon J  Gál S  Liptay G 《Talanta》1966,13(1):67-80
Thirteen sodium salts have been investigated derivatographically. The weight change, rate of weight change and enthalpy change of the salts have been measured as a function of temperature. The temperatures at which the salts may be dried without decomposition are given. Some of the curves are explained in terms of the effects of heat and gaseous products on the structure of the salts.  相似文献   

7.
本文提出测定4-溴-2-硝基苯胺(1)及其副反应产物的高效液相色谱(HPLC)分析方法。用紫外光谱、红外光谱、核磁共振氢谱鉴定(1)及副产物4,6-二溴-2-硝基苯胺(2)的结构。高效液相色谱采用的色谱柱为CLC-Ph柱(φ6×150mm),流动相为甲醇-水(70:30),测定的变异系数对于(1)和(2)分别为0.45%和1.07%,回收率分别为99.5%和99.7%。  相似文献   

8.
施敏 《中国化学》2000,18(6):936-939
Photolysis of diethyl ether-oxygen charge transfer complex in the presence of Sn(Ⅱ)or Cu(Ⅱ)salts gave higher yields of the oxidation products,ethyl acetate,acetaldehyde,ethanol,ethyl formate and methanol compared with those without the salts.In addition,the photolysis of an oxygen saturated te-trahydrofuran(THF)or dibutyl ether solution gave y-butyro-lactone or butanol and butyl butyrate as major products with small amounts of undetermined compounds,respectively.Their yields were also affected by the addition of Cu(Ⅱ)or Sn(Ⅱ)salts.  相似文献   

9.
为了探明手性季铵盐中N-手性在不对称烷基化反应中的作用,从天然氨基酸出发合成了4个仅含C-手性的季铵盐.将它们与4个同时含有C-和N-手性的季铵盐用于催化二苯亚胺甘氨酸叔丁酯的不对称烷基化反应,通过对烷基化产物的ee值进行比较,结果表明简单的链状季铵盐中的N-手性不能对烷基化产物的ee值产生明显影响.  相似文献   

10.
The photo‐initiated cationic polymerization (PCP) of epoxides using diaryliodonium salt photoacid generators (PAGs) bearing alkyl groups and anions was investigated. The properties and reactivities of a series of iodonium salts containing various cations and anions were compared in the context of a PCP reaction. The products from the decomposition of the cations of these salts were analyzed using gas chromatography‐mass spectrometry (GC‐MS) spectra. The relationship between the molecular structure of the salts and their reaction mechanism in the PCP reaction was investigated. Based on the results of the investigation, it was concluded that the structures of the cations and anions of theiodonium salts affect the PCP reaction rate, which was controlled by the products from the diaryliodonium salts. As part of an additional investigation, the diaryliodonium salts‐epoxide materials were applied to 254 nm‐photo‐patterning. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

11.
The catalytic potential of imidazolium salts in the benzoin condensation was investigated. Various aromatic aldehydes were tested in the benzoin condensation under the optimised protocol to afford α-hydroxyketones using N-heterocyclic carbenes derived from mono- and dicationic imidazolium salts. The products were obtained in good yields within short reaction times. Dicationic imidazolium salts with a long aliphatic chain between the imidazole rings were found to be more effective pre-catalysts for the benzoin condensation in comparison to the corresponding monocationic salts having the same aliphatic chain length.  相似文献   

12.
Gas-solid and solid-solid techniques allow for waste-free and quantitative syntheses in the chemistry of diazonium salts. Five techniques for diazotations with the reactive gases NO(2), NO and NOCl are studied. Two types are mechanistically investigated with atomic force microscopy (AFM) and are interpreted on the basis of known crystal packings. The same principles apply to the cascade reactions that had been derived from one-step reactions. Solid diazonium salts couple quantitatively with solid diphenylamine and anilines to give the triazenes. Azo couplings are achieved with quantitative yields by cautious co-grinding of solid diazonium salts with beta-naphthol and C-H acidic heterocycles, such as barbituric acids or pyrazolinones. Solid diazonium salts may be more easily applied in a stoichiometric ratio for couplings in solution. Co-grinding of solid diazonium salts with KI gives quantitative yields of various solid aryl iodides. The unavoidable coupling products in salt reactions are completely separated from the insoluble products in a highly benign manner. The solid-state reactions compare favourably with similar solution reactions that produce much waste. The structures of the products are elucidated with IR and NMR spectroscopy and mass spectrometry, while the tautomeric properties of the compounds are studied with density functional calculations at the B3LYP/6-31G* and BLYP/6-31G** levels.  相似文献   

13.
The reaction of thiooxindoles with various 2- and 3-substituted pyridinium salts afforded a variety of functionalized thiazocinoindoles. The products have been prepared in good to excellent yields by regioselective dinucleophilic C/S-cyclocondensation of thiooxindoles with pyridinium salts.  相似文献   

14.
噻二唑及其衍生物的制备   总被引:14,自引:0,他引:14  
合成了2,5-二流基-1,3,4-噻二唑及其八种胺盐衍生物和两种Mannich反应衍生物。测定了胺盐衍生物的部分物理常数和两种Mannich反应物的红外光谱、核磁1H谱数据,为杂环化合物润滑油添加剂的开发奠定基础。  相似文献   

15.
The mineralization of the products of detoxification (neutralization) of yperite-lewisite mixture by electrochemical oxidation was studied. A procedure for separation of potassium salts and arsenic compounds by electrocoagulation was developed. A possibility of using the resulting potassium salts as fertilizers for agriculture was discussed.  相似文献   

16.
A variety of organometallic reagents have been found to undergo regioselective reaction with 1-aryl-vinamidinium salts and 3-aryl-3-chloropropeniminium salts. The products of such reactions were found to be α,β-unsaturated ketones and chlorovinyl amines, respectively.  相似文献   

17.
Summary In the presence of copper powder the decomposition of aryl diazonium borofluorides in nitrobenzene and ethyl benzoate gives products of homolytic splitting of the diazonium salts. The synthesis of metalloorganic compounds from diazonium salts in the presence of metals occurs by a homolytic mechanism.  相似文献   

18.
Analysis of the products from the nickel (II) bromide catalysed arylation of tricoordinated phosphorus compounds R2P-Z (Z  H, Cl, SR, NR2 pointed out that this arylation always takes place on phosphorus resulting at first in formation of pseudophosphonium salts. Only the aminophosphonium salts are stable under reaction conditions; the other salts undergo several transformations which can be brought together in a general reactivity scheme to account for all the side products. On regard to other heteroatoms these results point out a particular ability of phosphorus to be arylated under nickel (II) catalysis.The reaction with secondary phosphines can be applied to synthetise diarylphosphonium salts.  相似文献   

19.
Thermal ionization on the surface of a heated wire is applied to the volatilization products of alkali salts of carboxylic and sulfonic acids, and to quaternary ammonium salts. The mass spectra of the alkali salts exhibit almost exclusively cationized molecules. They provide evidence for the evaporation of intact clustered molecules even under conditions of a slow rate of evaporation of the salts. The method appears to be of interest for selective detection of alkali salts from complex mixtures. With the ammonium salts [R4N]+ ions are formed by thermal surface ionization of intact salt molecules. The evaporation of these molecules could be detected at rather low temperatures.  相似文献   

20.
The rearrangement of 2-thienyl- and 2-furylalkylpyridinium salts to the corresponding anilines by the action of methylammonium sulfites has been studied. It has been shown that the rearrangement of these salts is accompanied in many cases by the formation of phenols and dealkylation products. The influence of the length of the alkyl chain between the heterocyclic rings on the ratio of the rearrangement products has been investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 368–371, March, 1986.  相似文献   

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