123-43-3Relevant articles and documents
Catalysis and mechanistic study of Ru(III) and Os(VIII) on the oxidation of taurine by BAT in acid and alkaline media: a kinetic modeling
Suresha, Nathegowda,Raj, Kalyan,Subramanya, Malini
, p. 500 - 507 (2021)
The study of oxidation kinetics of drug molecules is of much noteworthy in order to understand their mechanistic chemistry in redox systems. Taurine, being a potent drug molecule, has a wide range of activities in biological system. Therefore, the kinetics of oxidation of taurine (TAU) by bromamine-T (BAT) in HCl medium, catalyzed by Ru(III) and in NaOH medium, catalyzed by Os(VIII) has been investigated at 313 K. The rate law in acidic medium is: rate = k[BAT] t [TAU]0[Ru(III)]0.95[H+]?0.67. But, it takes the form, rate = k[BAT] t [TAU]0.46[Os(VIII)]0.89[OH?]?0.53 in basic medium. Addition of halide ions and p-toluenesulfonamide had no significant effect on the rate in both the cases. Decrease in dielectric constant of medium decreases the reaction rate in both the media. The conjugate acid, CH3C6H4SO2NHBr (TsNHBr), is assumed to be the oxidizing species in both the media. Equilibrium and decomposition constants have been evaluated in each case.
3,5-Dimethylpyrazole promoted sulfonation of acetic anhydride by H 2SO4 to sulfoacetic acid and methanedisulfonic acid, and crystal structures of the complexes with Co2+, Zn2+, Ba2+, Pb2+ and Cs+
Jianrattanasawat, Sarut,Mezei, Gellert
, p. 318 - 323 (2012)
Sulfuric acid can sulfonate acetic anhydride (but not acetic acid) to sulfoacetic acid, and also to methanedisulfonic acid in the presence of 3,5-dimethylpyrazole. Under the experimental conditions employed, sulfonation of 3,5-dimethylpyrazole with concentrated sulfuric acid in acetic anhydride/acetic acid as solvent leads to a mixture of approximately 47 mol% 3,5-dimethylpyrazole-4-sulfonic acid, 34 mol% sulfoacetic acid and 19 mol% methanedisulfonic acid, as determined by 1H NMR spectroscopy. The Co2+, Zn2+, Ba2+ and Pb2+ complexes of the sulfoacetate ligand, as well as the Cs+ complex of the methanedisulfonate ligand were isolated upon crystallization of the compounds obtained from the reaction of the above ligand mixture with the corresponding metal oxide or carbonate in water. Single-crystal X-ray crystallography of Co(O3SCH2CO2)(H2O)3, Zn(O3SCH2CO2)(H2O)3, Ba(O3SCH2CO2)(H2O), Pb(O 3SCH2CO2)(H2O) and Cs 2(O3SCH2SO3) reveals a variety of new coordination modes of the two sulfonated ligands within those structures.
Identification of low molecular weight organic acids by ion chromatography/hybrid quadrupole time-of-flight mass spectrometry during Uniblu-A ozonation
Amorisco, Apollonia,Locaputo, Vito,Pastore, Carlo,Mascolo, Giuseppe
, p. 187 - 199 (2013/02/23)
RATIONALE: The balance of organic nitrogen and sulfur during ozonation of organic pollutants often shows a lack of complete mineralization. It follows that polar and ionic byproducts are likely to be present that are difficult to identify by liquid chromatography/mass spectrometry (LC/MS). METHODS: The structural elucidation of low molecular weight organic acids arising from Uniblu-OH ozonation has been investigated by ion chromatography/electrospray tandem mass spectrometry (IC/ESIMS/MS) employing a quadrupole timeofflight mass spectrometer. Unequivocal elemental composition of the byproducts was determined by a combination of mass accuracy and high spectral accuracy. RESULTS: The employed identification strategy was demonstrated to be a powerful method of unequivocally assigning a single chemical composition to each identified compound. The exact mass measurements of [M-H]- ions allowed the elemental formulae and related structures of eighteen byproducts to be determined confidently. The main degradation pathways were found to be decarboxylation and oxidation. The experimental procedure allowed the identification of both nitrogen- and sulfur-containing organic acid by-products arising from Uniblu-OH ozonation. CONCLUSIONS: The obtained results are of environmental relevance for the balance of organic nitrogen and sulfur during the ozonation of organic pollutants due to the lack of complete mineralization of the compounds containing these atoms. Copyright 2012 John Wiley & Sons, Ltd. Copyright
Formation of the bisulfite anion (HSO3 -, m/z 81) upon collision-induced dissociation of anions derived from organic sulfonic acids
Jariwala, Freneil B.,Wood, Ryan E.,Nishshanka, Upul,Attygalle, Athula B.
experimental part, p. 529 - 538 (2012/08/28)
In the negative-ion collision-induced dissociation mass spectra of most organic sulfonates, the base peak is observed at m/z 80 for the sulfur trioxide radical anion (SO3 -·). In contrast, the product-ion spectra of a few sulfonates, such as cysteic acid, aminomethanesulfonate, and 2-phenylethanesulfonate, show the base peak at m/z 81 for the bisulfite anion (HSO3 - ). An investigation with an extensive variety of sulfonates revealed that the presence of a hydrogen atom at the β-position relative to the sulfur atom is a prerequisite for the formation of the bisulfite anion. The formation of HSO3 - is highly favored when the atom at the β-position is nitrogen, or the leaving neutral species is a highly conjugated molecule such as styrene or acrylic acid. Deuterium-exchange experiments with aminomethanesulfonate demonstrated that the hydrogen for HSO3 - formation is transferred from the β-position. The presence of a peak at m/z 80 in the spectrum of 2-sulfoacetic acid, in contrast to a peak at m/z 81 in that of 3-sulfopropanoic acid, corroborated the proposed hydrogen transfer mechanism. For diacidic compounds, such as 4-sulfobutanoic acid and cysteic acid, the m/z 81 ion can be formed by an alternative mechanism, in which the negative charge of the carboxylate moiety attacks the α-carbon relative to the sulfur atom. Experiments conducted with deuterium-exchanged and deuterium-labeled analogs of sulfocarboxylic acids demonstrated that the formation of the bisulfite anion resulted either from a hydrogen transfer from the β-carbon, or from a direct attack by the carboxylate moiety on the α-carbon. Copyright
THIOCOLCHICINE DERIVATIVES, METHOD OF MAKING AND METHODS OF USE THEREOF
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Page/Page column 27, (2010/12/26)
Disclosed herein are thiocolchicine derivatives suitable for use as muscle relaxants, methods of making the derivatives, and compositions comprising the derivatives.
Process for oxidation of methane to acetic acid
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Page/Page column 3-5; sheet 1-3, (2008/06/13)
Acetic acid or derivatives such as methyl acetate and acetyl sulfate, are produced from methane by contacting a methane-containing feed with an oxygen-containing gas in the presence of a palladium-containing catalyst and an acid selected from concentrated sulfuric acid and fuming sulfuric acid. The process is carried out using an oxygen partial pressure of from about 30 to about 300 psi and most preferably from about 60 to about 200 psi, a methane partial pressure of from about 100 to about 1000 psi, and most preferably from about 100 to about 400 psi, and a total pressure of oxygen and methane of from about 130 to about 1300 psi, preferably from about 200 to about 600 psi. The process is carried out in the absence of a catalyst promoter.
Process for preparing pyrylium salts
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, (2008/06/13)
A process for selectively preparing isomers of polysubstituted pyrylium salts from isoolefins or isoolefin precursors comprises diacylating the isoolefin or isoolefin precursor with a carboxylic acid anhydride in the presence of an acid having a Hammett acidity function, at about 22°-25° C. when pure, between -10 and -5. This method is selective to obtain the most substituted isomer of pyrylium salt that can be obtained from the isoolefin or isoolefin precursor.
Selectivite de la scission Si-C dans des composes du type Me3SiCH2Σ; une synthese originale et sure de l'iodoacetate d'ethyle
Bordeau, M.,Djamei, S. M.,Dunogues, J.
, p. 413 - 417 (2007/10/02)
The regiochemistry of the electrophilic cleavage of the SiCsp3 bond in compounds Me3SiCH2Σ (Σ = Me, Pr, Cl, COOEt) and Me3SiCHΣ2 (Σ = Cl) has been investigated using ICl, Me3SiOSO2Cl and HO3SCl as the electrophiles.When Σ = Pr or Cl a regioselective cleavage of the Si-CH3 bond was observed, producing silylated chlorosulfonates or sulfates which often were new compounds.With Σ = COOEt a regiospecific splitting of the Si-CH2COOEt bond was observed.This confirms the synthetic potential of ethyl trimethylsilylacetate.
Keto-Enol Equilibria in Mixed Acetic Sulphuric Anhydrides
Montoneri, Enzo,Tempesti, Ezio,Giuffre, Luigi,Castoldi, Aldo
, p. 662 - 667 (2007/10/02)
Mixed acetic sulphuric anhydrides obtained from both equimolar SO3-AcOH and SO3-Ac2O systems in liquid SO2 are found at low temperature (=.CO.OSO3Y) and enol (CH:COH.OSO3Y) forms (Y=SO3(1-) or Ac).At room temperature a cleavage reaction is shown to occur through the intermediacy of keten, which reacts further to yield oligomers and sulpho-derivatives . This cleavage reaction appears specifically not to involve participation of acetylium ions, whereas previously these ions were normally considered as the principal precursor of keten intermediates.
