- Rearrangement of Aromatic Sulfonate Anions in the Gas Phase
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Collisionally activated dissociation of deprotonated aromatic sulfonic acids in the gas phase causes rearrangement and fragmentation to produce the corresponding phenoxide ions.The mechanism for this reaction has been investigated and the results of this study favor initial intramolecular nucleophilic addition of a sulfonate oxygen atom to the aromatic ring, a process which is followed by heterolytic cleavage of the carbon-sulfur bond to rearomatize the ring.The product from this addition-elimination sequence is the anion of a sulfurous acid half-ester, which loses SO2 to generate the corresponding phenoxide ion.
- Binkley, Roger W.,Flechtner, Thomas W.,Tevesz, Michael J. S.,Winnik, Witold,Zhong, Boyu
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Read Online
- Oxidative Degradation of Azo Dyes in Aqueous Solution by Water-Soluble Iron Porphyrin Catalyst
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Textile and food industries produce a significant volume of effluents containing azo dyes and other pollutants. These effluents are serious environmental threats, and new methods for their treatment and for the degradation of azo dyes are thus attracting much attention. The current study deals with the oxidative degradation of azo dyes by meso-tetrakis(1-methylpyridinium-4-yl)prophyrinatoiron(III), [FeIII(tmpyp)], and meta-chloroperoxy benzoic acid (m-CPBA) in aqueous solution at room temperature. The catalytic degradation of azo dyes was investigated by using rapid-scan stopped-flow spectrophotometry as a function of solution pH, [catalyst], [m-CPBA], [dye] and [surfactants]. To obtain mechanistic insight, the reaction between [FeIII(tmpyp)] and m-CPBA was also studied in aqueous solution in absence of azo dyes. Spectral analyses and kinetic data show that [FeIII(tmpyp)] is transformed into the transient intermediate [FeIV(O)(tmpyp)].+ (a compound I analog) within 20–30 ms followed by the formation of relatively stable [FeIV(O)(tmpyp)] (a compound II analog). Batch experiments reveal that the dye degradation rate is influenced by the solution pH and the concentrations of [FeIII(tmpyp)], m-CPBA, dye, and surfactants. On the basis of the kinetic and spectroscopic data, a mechanistic scheme for the dye degradation reaction and a steady-state rate equation are proposed. The products resulting from oxidative degradation of the azo dye amaranth have been analyzed by HPLC-UV-HRMS.
- Saha, Tapan Kumar,Frauendorf, Holm,Meyer, Franc
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p. 2870 - 2881
(2021/07/14)
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- Cornforth and Corey-Suggs reagents as efficient catalysts for sulfonation of aromatic and heteroaromatic compounds using NaHSO3 under solvent free and microwave conditions
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Cornforth and Corey-Suggs reagents Pyridinium Dichromate (PDC) and Pyridinium Chlorochromate (PCC) were explored as efficient catalysts for sulfonation of aromatic and heteroaromatic compounds using NaHSO3 in aqueous acetonitrile medium at room temperature within 1–4 h, while microwave assisted reactions took place within 1–4 min under solvent-free conditions. These observations indicate significant rate accelerations in microwave assisted reactions. which were explained due to the bulk activation of molecules induced by insitu generated high temperatures and pressures when microwaves are transmitted through reaction medium.
- Fatima, Touheeth,Duguta, Govardhan,Purugula, Venkanna,Yelike, Hemanth Sriram,Kamatala, Chinna Rajanna
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p. 1001 - 1006
(2020/07/27)
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- Sustainable access to sulfonic acids from halides and thiourea dioxide with air
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A sustainable and mild one-step strategy is explored for the synthesis of aryl and alkyl sulfonic acids using a facile combination of halides and sulfur dioxide surrogates under air. The cheap industrial material thiourea dioxide was employed as an eco-friendly and easy-handling sulfur dioxide surrogate, while air was used as a green oxidant. Both aryl and alkyl sulfonic acids were obtained under transition metal-catalyzed or transition metal-free conditions. Mechanistic studies demonstrated that sulfinate was involved as an intermediate in this transformation. Notably, this protocol has been applied to the late-stage sulfonation of the drugs naproxen, isoxepac and ibuprofen.
- Zhang, Hui,Wang, Ming,Jiang, Xuefeng
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supporting information
p. 8238 - 8242
(2020/12/29)
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- Aryl and alkyl sulfonic acid compounds as well as construction method adopting inorganic sulfur salt and application
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The invention discloses aryl and alkyl sulfonic acid compounds as shown in a formula (1) and a synthesis method thereof. The method comprises the following step: aromatic iodine and an inorganic sulfur source or alkyl bromide and an inorganic sulfur source as reaction raw materials react in a solvent under the action of alkali, a catalyst or an additive to obtain a series of aryl and alkyl sulfonic acid compounds. According to the method, the aryl and alkyl sulfonic acid compounds are constructed in one step by taking an inorganic sulfur reagent as a sulfur source, so that the defect of the mode in which the aryl and alkyl sulfonic acid compounds are synthesized by taking concentrated sulfuric acid, chlorosulfonic acid or sulfur dioxide gas and the like as sulfonating reagents in the priorart is avoided. The aryl and alkyl sulfonic acid compounds developed by the invention can be used for synthesizing aryl and alkyl sulfonic acid drug analogues.
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Paragraph 0046-0049; 0104-0107
(2020/09/16)
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- Synthetic process of naphthol
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The invention discloses a synthetic process of naphthol. The process comprises the followings steps: sulfonation, neutralization, alkali fusion, and acidification. The sulfonation step comprises the following steps: a sulfonation reaction is carried out for naphthalene and sulfuric acid whose mass fraction is 98% in the existence of a water carrying agent, a characteristic that the water carrying agent and water form an azeotrope is applied, water which is generated in the reaction is separated continuously from a reaction system, and naphthalene and sulfuric acid are nearly reacted completely. Obtained 1-naphthalenesulfonic acid is neutralized, alkali fusion and acidification are directly carried out in order to obtain a naphthol crude product. The process has the advantages of simplified operation, little low of naphthalene and sulfuric acid, high utilization rate, high naphthalene conversion rate which reaches 94% or above, low amount of waste water, and a few amount of sodium sulfate waste water which is only generated after multiple circulations.
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Paragraph 0017; 0018; 0019; 0020; 0021; 0022
(2017/08/29)
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- Method for continuously producing 1-naphthalene sulfonic acid
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The invention belongs to the field of organic matter sulfonation, and particularly relates to a method for continuously producing 1-naphthalene sulfonic acid. The method particularly includes the steps: adding naphthalene and sulfur trioxide into a sulfonation reactor for sulfonation reaction to obtain mixture containing the 1-naphthalene sulfonic acid; adding solvents into the mixture to perform solid-liquid separation to obtain the 1-naphthalene sulfonic acid and mother liquor; circulating the mother liquor to sulfonation reaction. The naphthalene is in a solid or melted liquid state, and the sulfur trioxide is in a gas or liquid state. The method for continuously producing the 1-naphthalene sulfonic acid avoids waste acid, can also realize tail gas treatment and solvent recovery and is efficient, environmentally friendly and suitable for large-scale continuous production, solvent loss is reduced, complicated separation steps are omitted, and production cost is greatly reduced.
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Paragraph 0072-0078
(2017/06/19)
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- Preparation method of 1-naphthylamine-5-sulfonic acid
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The invention discloses a preparation method of 1-naphthylamine-5-sulfonic acid. The preparation method comprises the following steps of step one, sulfonation: refined naphthalene is added after sulfuric acid is added to a sulfonation pot and stirred, steam is turned on for warming, and the reaction is kept for a period of time; then second batch of sulfuric acid is added, and the reaction is kept for a period of time; step two, nitrification: nitric acid is added, the temperature is controlled, and the reaction is kept for a period of time; the acidity is enabled to reach 45%-46%, and the amino value is larger than or equal to 410 g/kg; step three, neutralization: dolomite suspension liquid is added, excess sulfuric acid and hydrogen ions on the sulfonic acid group are neutralized, and the end point is reached if the color of congo red test paper doesn't change into blue; step four, reduction: iron powder is added, the reduction rate is controlled to be above 99%, and the amino value is controlled to be between 90 g/t to 110 g/t; step five, acidification: 1-naphthylamine-8-sulfonic acid is subjected to acidification separation to prepare 1-naphthylamine-5-sulfonic acid mother liquor; step six, the 1-naphthylamine-5-sulfonic acid mother liquor is acidized to further prepare the 1-naphthylamine-5-sulfonic acid.
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Paragraph 0055; 0056; 0057; 0058; 0059; 0060; 0061-0063
(2016/10/17)
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- Method for hydrogen catalyzed preparation of 1-naphthylamine-8-sulfonic acid
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The invention discloses a method for hydrogen catalyzed preparation of 1-naphthylamine-8-sulfonic acid. The method includes the reduction steps of: placing a solution containing 1-sulfonyl-8-nitronaphthalene in a reduction pot, adding nickel powder, conducting starting and stirring, enclosing the reduction pot and pumping vacuum, then introducing hydrogen and maintaining the pressure at 1.2-1.3MPa, heating the mixed liquid to a temperature of 100-110DEG C, pumping out the mixed liquid from the bottom continuously and letting it flow into the reduction pot from the top, at the same time pumping out the gas from the top continuously and blowing the gas into the reduction pot from the bottom. The method for hydrogen catalyzed preparation of 1-naphthylamine-8-sulfonic acid provided by the invention can prepare the 1-naphthylamine-8-sulfonic acid product meeting the market requirements, and also can overcome the disadvantages of existing iron powder catalyzed preparation methods.
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Paragraph 0011; 0012; 0013; 0014; 0015; 0016; 0017
(2016/10/20)
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- A dilute sulfuric acid recovery method for using (by machine translation)
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The invention discloses a method for recovering and utilizing dilute sulfuric acid, characterized in that comprises the following steps: in the reaction with rectification, the dilute sulfuric acid and double-ring aromatic hydrocarbon, or/and polycyclic aromatic hydrocarbon in the distillation together with, in the rectification process, the water as the light component, from the rectification tower, the concentration of sulfuric acid in the kettle, the kettle warmly rise; when cauldron mass concentration of sulfuric acid in > 63% time, the temperature of the kettle for 150-175°C, sulfuric acid and double-ring aromatic hydrocarbon, or/and polycyclic aromatic sulfonation reaction occurs, the water is generated at the same time, and the concentration of sulfuric acid in the rectification heating water outlet, so cycle, until complete reaction consumption of sulfuric acid in the kettle. In the invention, the dilute sulfuric acid rectification concentrated use and double ring/multi-ring aromatic sulfonated combination, does not need high-temperature, can be realized by using concentrated and dilute sulfuric acid. (by machine translation)
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Paragraph 0021
(2016/11/24)
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- REDUCTION METHOD OF ARENESULFONAMIDE, PRODUCTION METHOD OF ARENESULFONIC ACID AND BINAPHTHYLDISULFONIC ACID
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PROBLEM TO BE SOLVED: To obtain a corresponding reduction body from an arenesulfonamide with good yields. SOLUTION: A N,N-dimethylnaphthalene-2-sulfonamide is reduced with 5 equivalents of Red-Al (NaAlH2(OC2H4OCH3)2), so that a corresponding sulfinic acid is obtained with good yields. The sulfinic acid is oxidized with oxygen (1 atm), so that a corresponding naphthalene-2-sulfonic acid is obtained. COPYRIGHT: (C)2015,JPO&INPIT
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Paragraph 0029; 0031; 0034
(2016/11/17)
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- A novel method for sulfonation of aromatic rings with silica sulfuric acid
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Direct and chemoselective sulfonation of aromatic compounds with silica sulfuric acid in 1,2-dichloeoethane or under solvent-free conditions.
- Hajipour, Abdol R.,Mirjalili, Bi Bi F.,Zarei, Amin,Khazdooz, Leila,Ruoho
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p. 6607 - 6609
(2007/10/03)
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- Clean-chemistry sulfonation of aromatics
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A solution of TFAA/H2SO4 is an atom-efficient liquid-phase system for rapid sulfonation of aromatic structures; H2SO4 is consumed stoichiometrically and the spent trifluoroacetic anhydride (TFAA) is readily recovered as trifluoroacetic acid (TFA) which can be recycled to TFAA.
- Corby, Brian W.,Gray, Anthony D.,Meaney, Padraig J.,Falvey, Michael J.,Lawrence, Gregory P.,Smyth, Timothy P.
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p. 326 - 327
(2007/10/03)
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- Exploiting differences in solution vs solid-supported reactivity for the synthesis of sulfonic acid derivatives
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(matrix presented) Quantitative We describe a method herein for the protection of aryl and alkyl sulfonates during synthesis which employs commercially available Wang or MBOH resin, both of which terminate as benzyl alcohols, as both a protecting group and "traceless" linker. Given the known instability of benzylic sulfonate esters to nucleophilic displacement in solution, this linkage is surprisingly stable: no loss of either aryl or alkyl sulfonates is observed when the resin is exposed to a wide variety of organic bases and solvents at room temperature. Further elaboration of the resin-bound sulfonates via Suzuki coupling is also described.
- Hari, Anitha,Miller, Benjamin L.
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p. 2109 - 2111
(2008/02/10)
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- Compounds of the s-triazine series
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The compounds of the s-triazine series of formula I STR1 wherein the symbols R1, R2, R3, X and n possess the significances given in claim 1, are eminently suitable, when applied to textile material, as UV-absorbers, as resist agents for anionic dyes, and as stain blockers.
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- Modelization and kinetic simulation of naphthalene sulfonation by 20percent oleum
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This study represents a modelization procedure for the kinetic analysis of naphthalene sulfonation using 20percent oleum at temperature 393 K.The sulfonation involves many consecutive, parallel and reversible reactions.Representative samples of the reaction mixture are analyzed by high-performance liquid chromatography for quantitative determination of the produced sulfonic acid isomers as well of the remaining naphthalene.The kinetics obtained this way allow to suggest a model describing the concentration evolution of four components in the reaction mixture.Therefore, six main reactions are taken into account, the kinetic parameters of which are estimated by the fitting of experimental data, using a weighed least-squares method based on minimizing the deviation between calculated and experimental data. - Keywords: modelization; naphthalene sulfonation; 20percent oleum; kinetics; naphthalenesulfonic acid
- Aleboyeh, Hamid,Kille, Gerard,Walter, Serge,Aleboyeh, Azam,Ladhari, Neji
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p. 677 - 682
(2007/10/03)
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- Sulfonation and Desulfonation of Naphthalene under Conditions of Microwave Activation
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Microwave activation sharply curtails the time required for sulfonation of naphthalene and allows this reaction to be performed with less concentrated sulfuric acid. The consumption of sulfuric acid is decreased. Moreover, under certain conditions the ratio of isomeric sulfonic acids can be changed toward α or β isomer. Microwave radiation also accelerates desulfonation of β-naphthalenesulfonic acid in solutions with low pH.
- El'tsov,Sokolova,Dmitrieva
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p. 295 - 299
(2007/10/03)
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- Process for releasing acidic organic compounds from salts thereof by carbon dioxide
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This invention embodies a process for releasing acidic organic compounds in high yield and good purity from aqueous solutions of their salts which comprises converting the salts by carbon dioxide to their corresponding free acidic organic compounds and metal hydrogen carbonates, removing the acidic organic compounds from the mixture by extraction with an essentially water-insoluble organic solvent, and re-extracting the organic phase with carbon dioxide containing water. Using this process, the acidic organic compounds are completely released from their corresponding salts, i.e., the organic solution is free of salt. The acidic organic compounds released by the claimed process are organic compounds which contain acidic protons which can be replaced by metals. Some examples are carboxylic acids, sulfonic acids, phosphonic acids, phenols, naphthols, and aliphatic alcohols.
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- The positional reactivity order in the sulfur trioxide sulfonation of benzene and naphtalene derivatives containing an electron-withdrawing substituent
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The reaction of sulfur trioxide with derivatives of benzene and naphthalene containing an electron-withdrawing substituent, viz.-SO3H, -SO2Ph, -NO2, -CHO, -COPh, -CO2H, and -CO2Me, in dichloromethane as solvent at ca. 22 deg C has been studied by analysis of the resulting mixtures of the sulfo derivatives with 1H-NMR.The initial sulfonation of the benzene derivatives yields the corresponding 3-sulfonic acid (3-S) and subsequently, with the exception of nitrobenzene and methyl benzoate, small amounts of 3,5-S2.Benzenesulfonic acid in addition undergoes sulfonylation giving 3,3'-di- and 3,5,3'-trisulfodiphenyl sulfone.Monosulfonation of naphtalene-1-S yields the 1,5-S2, 1,6-S2 and 1,7-S2 derivatives in a ratio of 71:20:9.On using a large excess of SO3, the eventual products are 1,3,5-S3, 1,3,6-S3 and 1,3,5,7-S4.Monosulfonation of naphthalene yields 5-S, 6-S, 7-S and 8-S in a 55:9:6:30 ratio, that of 1-benzoylnaphthalene 5-S, 6-S and 7-S in a ratio of 83:11:6, and 1-nitronaphtalene only the 5-S.The absence of peri sulfonation with 1-sulfo-, 1-benzoyl- and 1-nitronaphthalene is due to prohibitive steric hidrance. 1-Naphthoic acid and its methyl ester upon SO3 sulfonation and aqueous work-up both yield 5- and 8-sulfonaphthoic acid in a ratio of 65:35 and 77:21, respectively.The initially formed peri-substituted product is the intramolecular anhydride of 8-sulfo-1-naphthoic acid (5).All the 2-substituted naphthalenes yield 5-S and 8-S upon SO3 sulfonation of which the former sulfo isomer is far in excess.The positional reactivity orders for the SO3 sulfonation of the monosubstituted naphthalene derivatives are discussed in terms of the difference in reactivity of the α- and β-positions, and the steric and electronic effects of the deactivating substituent.
- Cerfontain, Hans,Zou, Yousi,Bakker, Bert H.
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p. 403 - 410
(2007/10/02)
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- Microwave heating as a new way to induce selectivity between competitive reactions. Application to isomeric ratio control in sulfonation of naphthalene
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Heating rate associated with microwave heating are used to control isomeric ratio in sulfonation of naphtalene. General considerations about use of microwave heating in organic syntheses are also considered. The authors show specificities of microwave heating in term of reactivity, associated with control of very fast heating rate.
- Stuerga,Gonon,Lallemant
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p. 6229 - 6234
(2007/10/02)
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- APPLICATION OF MICROWAVE ENERGY TO ORGANIC SYBNTHESIS: IMPROVED TECHNOLOGY
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The application of microwave energy to the sulfonation of naphthalene and anthraquinone, to the amination of p-chloronitrobenzene, and to the hydrosilylation of 2- and 4-vinylpyridine has been studied.Though faster (5-360-fold) reactions were observed problems were encountered with the available microwave technology.These were overcome by using a microwave oven equipped with stirring facility and both temperature and pressure control.
- Abramovitch, R. A.,Abramovitch, D. A.,Iyanar, K.,Tamareselvy, K.
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p. 5251 - 5254
(2007/10/02)
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- Monoazo dyes, process for their preparation, and the use thereof
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The invention relates to monoazo dyes of the formula STR1 wherein K is the radical of a coupling component of the benzene, naphthalene or heterocyclic series, and R is hydrogen, halogen, carboxy, a C1 -C6 alkyl, C1 -C6 alkoxy, C2 -C6 alkanoylamino, C1 -C6 alkylsulfonylamino, C1 -C6 alkylsulfonyl, phenyl(C1 -C4)alkylsulfonyl or naphthyl(C1 -C4)alkylsulfonyl or benzoyl radical, which radicals may be further substituted, or is a STR2 group, wherein each of R1 and R2 independently of the other is hydrogen or a C1 -C6 alkyl, C5 -C7 cycloalkyl, phenyl or naphthyl radical, which radicals may be further substituted, and wherein X is hydrogen, halogen or a C1 -C6 alkyl, C1 -C6 alkoxy, C2 -C6 alkanoylamino or C1 -C6 alkylsulfonylamino radical, which radicals may be further substituted. These dyes give dyeings of good light- and wetfastness properties on polyamide material.
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- Process for the sulphonation of aromatic compounds with sulphur trioxide
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A new process for the preparation of aromatic sulphonic acids, in which the sulphonation of the aromatic compounds is carried out with sulphur trioxide in organic solvents in the presence of hydrogen halide.
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- Linear Free Energy Relationship in Naphthalene System: Kinetics of Hydrolysis of 4-Substituted 1-Naphthalenesulphonyl Chlorides
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The kinetics of hydrolysis of several 4-substituted 1-naphthalenesulphonyl chlorides have been studied in aqueous acetone at three temperatures.The reaction is first order in sulphonyl chloride.Presence of electron-withdrawing substituents in the naphthyl ring enhances the rate while that of opposite ones retards it.The small ρ-values obtained in the correlation analysis using the Hammett and dual substituent parameter equations are consistent with either an SN2 or an SAN mechanism.
- Perumal, S.,Selvaraj, S.,Viswanathan, T. K.,Arumugam, N.
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p. 436 - 438
(2007/10/02)
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- Method for preparing α-naphthol
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A method for preparing α-naphthol according to the present invention comprises sulphonation of naphthalene with an equimolar amount of a concentrated sulphuric acid at a temperature ranging from 30° to 85° C. for a period of from 60 to 120 minutes in the presence of acetic anhydride whereafter αin an amount of from 0.5 to 1.5 mole per mole of naphthalene. The resulting naphthalene-α-sulphonic acid is fused with an alkali taken in an amount of 3-4 moles per mole of naphthalene-α-sulphonic acid at a temperature ranging from 180° to 285° C. for a period of from 10 to 30 minutes. The resulting melt consisting of the alkali metal α-naphtholate and the alkali metal sulphite is mixed with a polar solvent; the resulting mixture is acidified with a mineral acid taken in an amount equimolar relative to the alkali metal α-naphtholate, whereafterα-naphthol is separated from the resulting suspension. The method according to the present invention makes it possible to increase the yield of α-naphthol up to 98% of the theoretical amount and produce α-naththol with a purity of up to 99.5%.
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