- Biomimetic transformation and biological activities of globiferin, a terpenoid benzoquinone from Cordia globifera
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A new 10-membered ring meroterpene (1), named globiferin, was isolated from root extracts of Cordia globifera. Biomimetic transformations of 1 and its derivatives, either by acid cyclization or by Cope rearrangement, provided information relating to the b
- Dettrakul, Suppamit,Surerum, Sanya,Rajviroongit, Shuleewan,Kittakoop, Prasat
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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; 0076-0079
(2020/09/16)
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- Regioselective Sulfonation of Aromatic Compounds over 1,3-Disulfonic Acid Imidazolium Chloride under Aqueous Media
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1,3-Disulfonic acid imidazolium chloride ([Dsim]Cl), as a Bronsted acidic ionic liquid, is introduced for the sulfonation of aromatic compounds by in situ generation of sulfuric acid at 50 °C under mild conditions and in aqueous medium.
- Moosavi-Zare, Ahmad Reza,Zolfigol, Mohammad Ali,Noroozizadeh, Ehsan
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p. 1682 - 1684
(2016/07/06)
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- Sulfides, sulfones, and sulfoxides of the furan-2(5H)-one series. synthesis and structure
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A number of 4- and 5-R-sulfanylfuran-2(5H)-one derivatives were synthesized, and their oxidation with various reagents was studied. The corresponding sulfones were obtained using hydrogen peroxide in acetic acid. 4-R-sulfanyl derivatives were selectively oxidized to sulfoxides with m-chloroperoxybenzoic acid. The molecular and crystal structures of some new sulfones and sulfoxides were determined by X-ray analysis.
- Latypova,Saigitbatalova, E. Sh.,Chulakova,Lodochnikova,Kurbangalieva,Berdnikov,Chmutova
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p. 521 - 534
(2014/06/10)
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- A kinetic study of acid-catalyzed hydrolysis of some arylsulfonyl phthalimides
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The acid-catalyzed hydrolysis of arylsulfonyl phthalimides was studied in aqueous solutions of sulfuric, perchloric, and hydrochloric acid at 35.0 ± 0.1C. Analysis of the data by the excess acidity method and activation parameters, as well as substituent and solvent isotope effects, indicate hydrolysis by an A-2 mechanism at low acidity. At higher acidities, a changeover to an A-1 mechanism is observed.
- Kutuk, Halil,Ozturk, Seyhan
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scheme or table
p. 332 - 340
(2009/09/25)
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- General, fast, and high yield oxidation of thiols and disulfides to sulfonic and sulfinic acids using HOF·CH3CN
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Thiols and disulfides are oxidized to the corresponding sulfonic and sulfinic acids using HOF·CH3CN. This oxidation is suitable for a variety of thiols and disulfides and proceeds under mild conditions, in short reaction times and with high yields.
- Shefer, Neta,Carmeli, Mira,Rozen, Shlomo
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p. 8178 - 8181
(2008/03/14)
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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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- 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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- Reactivity of sterically hindered aromatic sulfonic acid derivatives: VII.* hydrolysis of arenesulfonyl chlorides in aqueous acetonitrile
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Hydrolysis of sterically hindered arenesulfonyl chlorides in aqueous acetonitrile is accelerated by both electron-acceptor and some electron-donor substituents in the benzene ring. A multifactor kinetic model of the process is proposed. 1998 MAHK Hayka/Interperiodica Publishing.
- Rubleva,Krut'ko,Mitchenko
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p. 1006 - 1009
(2007/10/03)
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- Synthesis of 3-chloro-Δ3-cephem-4-carboxylate by addition/cyclization of allenecarboxylate. Copper(II)-promoted aerobic oxidation of arenesulfinic acids
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The selective transformation of allenecarboxylate derived from penicillin into 3-chloro-Δ3-cephem-4-carboxylate was successfully achieved by an addition/cyclization reaction with chloride salts in aerobic media containing a copper(II) catalyst, in which copper(II)-catalyzed aerobic oxidation of in situ generated benzenesulfinate ion into less nucleophilic sulfonate ion prior to the nucleophilic addition of the former ion to the allenecarboxylate would completely eliminate the formation of undesired 3-phenylsulfonyl-Δ3-cephem-4-carboxylate. Under similar aerobic conditions, arenesulfinates salts and arenesulfinic acids were smoothly oxidized to the corresponding sulfonate salts and sulfonic acids, respectively.
- Tanaka, Hideo,Kikuchi, Ryo,Torii, Sigeru
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p. 1391 - 1396
(2007/10/03)
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- REACTIVITY OF STERICALLY HINDERED DERIVATIVES OF AROMATIC SULFONIC ACIDS II. EFFECTS OF SUBSTRATE STRUCTURE AND MEDIUM POLARITY ON THE HYDROLYSIS OF BENZENESULFONYL CHLORIDES
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The kinetics of the hydrolysis of substituted benzenesulfonyl chlorides XArSO2ClN2 mechanism.
- Vizgert, R. V.,Rubleva, L. I.,Maksimenko, N. N.
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p. 2259 - 2262
(2007/10/02)
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- Oxygen scrambling and stereochemistry during the trifluoroethanolysis of optically active 2-butyl 4-bromobenzenesulfonate
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It is shown that during the trifluoroethanolysis of 2-butyl 4-bromobenzenesulfonate, containing 18O in the nonbridging oxygens, scrambling of the oxygen label occurs. When enantiomerically enriched 2-butyl 4-bromobenzenesulfonate is subjected to the same solvolysis conditions, racemization of the starting ester is not observed. Therefore if an ion-pair intermediate is involved in the trifluoroethanolysis reaction, the ion pair has a sufficient lifetime to permit rotation of the anion leading to oxygen scrambling. However, rotation of the cation, which would lead to racemization, does not occur. The possibility that the oxygen scrambling may be a concerted reaction and not involve an ion-pair intermediate is discussed.
- Dietze, Paul E.,Wojciechowski, Marek
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p. 5240 - 5244
(2007/10/02)
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- REACTIVITY OF STERICALLY HINDERED DERIVATIVES OF AROMATIC SULFONIC ACIDS. I. EFFECT OF SUBSTITUENTS ON RATE AND MECHANISM OF HYDROLYSIS OF SOME SUBSTITUTED BENZENESULFONYL CHLORIDES
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The kinetics of the hydrolysis of substituted benzenesulfonyl chlorides XArSO2Cl in 70percent aqueous dioxane at 303, 313, and 323 K were studied by acid-base titration.The effect of the investigated set of substituents cannot be described by a single linear relationship of the Hammett type.The substrates containing methyl groups at the ortho positions of the aromatic ring exhibit enhanced reactivity.The effect of the structural changes in the sulfonyl chlorides on the nature of bond formation and cleavage in the transition state is discussed in terms of the SN2 mechanism.An attempt is made to explain the V-shaped form of the relationship between log k and ? from the standpoint of the hyperconjugation effect, the contribution from which amounts to about 10percent of the ρ value.
- Vizgert, R. V.,Rubleva, L. I.,Maksimenko, N. N.
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p. 727 - 730
(2007/10/02)
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- Multiple Structure-Reactivity Relationships for a Menschutkin-type SN2 Reaction
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The mechanism of nucleophilic displacement was studied by using three variable systems of ρX, ρY and ρZ obtained from the change of substituents X, Y and Z for the reaction of (Z)-substituted benzyl (X)-benzenesulphonates with (Y)-substituted N,N-dimethylanilines in aceton at 35 deg C.The coefficient of the interaction term, ρXY, has a value of 0.21 which means that bond-making and -breaking are concerted in the SN2 transition state.In the range Z = H to p-NO2, in which the SN2 mechanism is predicted to be dominant, the ρZY value is very large, 0.5, which means that the interaction between Z and Y is very large. ρZX is ca. 0.06 which means that the interaction is small between X and Z.In contrast, in the range Z = H to p-Me, in which the SN1 mechanism is dominant, the ρZY value is nearly zero, indicating no interaction between Z and Y.Changes of substituent effect and interaction terms, ρXY, ρYZ and ρZX are useful tools for distinguishing wrong reaction mechanisms.
- Yoh, Soo-Dong,Tsuno, Yuho,Fujio, Mizue,Sawada, Masami,Yukawa, Yasuhide
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- Structural Effects on the Transition States of Imine-Forming Eliminations in N-Substituted O-(Arylsulfonyl)hydroxylamines
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A series of amines with various alkyl and aryl substituents at C-1 were converted to the corresponding N-(arylsulfonoxy)amines, which served as precursors for base-promoted, imine-forming elimination.By varying the bases used to promote the elimination and by varying the leaving groups attached to nitrogen, the Broensted parameters β and βlgCH3 were determined.These were used to locate the transition state on the More O'Ferrall-Jencks energy surface for elimination.Substituents were found to influence the structure of the activated complex markedly.Resonance effects were most important, while inductive effects had little influence .
- Hoffman, Robert V.,Shankweiler, Jean M.
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p. 4019 - 4022
(2007/10/02)
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- Kinetics of hydrolysis of aromatic mono- and disulfonyl chlorides
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A continuous polarografic method of recording instantaneous concentrations of - SO2Cl groups in an aqueous acetic acid system containing CH3CO2Na has been elaborated.Ten model monosulfonyl chlorides underwent hydrolysis according to pseudo-first order kinetics (20percent H2O, 80percent v.v.CH3CO2H, 0.5 mol/dm3 CH3CO2Na).Plots of hydrolysis for seven disulfonyl dichlorides with different number of - CH3 groups have been determined.Pseudo-first order rate constants for two consecutive reactions of hydrolysis (k1 and k2) have been computed and the influence of -SO2Cl and -SO3- groups on the reactivity of the second group - SO2Cl has been discussed.The mechanism of nucleophilic substitution has also been discussed.
- Sanecki, Przemyslaw,Rokaszewski, Edward
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p. 2263 - 2267
(2007/10/02)
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- Solvent Effects on Solvolytic Reactivity. A Diagnostic Test for Neighboring-Group Assistance by ? Conjugation in Solvolysis Reactions
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The solvolysis rates of 13 arenesulfonates have been determined in mixtures of ethanol and water (the E-series solvents) and acetic acid and formic acid (the A-series solvents).The substrates studied include the following: neophyl (1), 2-adamantyl (2), neopentyl (3), and cyclooctyl (4) tosylates; cyclopropylcarbinyl pemsylate (5a) and tosylate (5b); exo-2-norbornyl tosylate (6); cyclobutylcarbinyl (7), cyclobutyl (8), and pinacolyl (9) brosylates; cyclopentyl (10), cyclohexyl (11), and 2-propyl (12) tosylates; and cyclopentylcarbinyl brosylate (13).Correlations of the rate data by eq 1 t(Y) = a + b log kt(neophyl-OTs)> showed that the various substrates responded differently to the examined solvent effects on the solvolytic reactivity.For compounds 2-4, linear correlations were obtained.For compounds 5-9, E-line, A-line dispersions were noted which diverged with increasing ionizing power; for compounds 10-12, parallel E-line, A-line dispersions were obtained; and for compound 13, an E-line, A-line dispersion was observed which converged with increasing ionizing power.Stastistical analyses of the rate data correlations confirmed the significance of the E or A classification of data.The results are interpreted in terms of differences in the involvement of solvent in the transition state for those solvolyses assisted by bridging from those assisted by C-C ? bond hyperconjugation.
- Roberts, Donald D.
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p. 2521 - 2526
(2007/10/02)
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- HYDROLYSIS OF AROMATIC SULFONIC ACIDS UNDER THERMODYNAMIC CONTROL OF THE REACTION
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Linear mathematical models which describe the hydrolysis of alkyl- and halobenzenesulfonyl acids under the conditions for their isomerization in sulfuric acid have been obtained by the method of mathematical experiment planning.The value of the effective rate constants of hydrolysis calculated according to the models for comparative conditions (150 deg C, 3 moles of 85percent sulfuric acid) were used to obtain the correlation between log kh and the ? constants of the substituents.The correlation corresponds the electrophilic nature of the hydrolysis process (ρ = -4.69).The strong influence of the electronic effects of the substituents on the rate of hydrolysis is an indication of the development of a considerable positive charge on the reaction center in the transition state.
- Krylov, E. N.,Volgina, L. V.,Isaeva, G. Yu.
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p. 1129 - 1133
(2007/10/02)
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- EFFECT OF STRUCTURE ON THE KINETICS AND MECHANISM OF THE ACID-CATALYZED DECOMPOSITION OF N-ALKYL-N-NITROBENZENESULFONAMIDES
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The decomposition rate of a series of meta- and para-substituted N-alkyl-N-nitrobenzenesufonamides was determined by a spectrophotometric method in aqueous sulfuric acid.It was shown that the decomposition of the compounds takes place both by denitration and by cleavage of the N-S bond with the formation fo primary aliphatic N-nitrosamines.Electron-withdrawing substituents in the aromatic ring shift the process toward denitration.
- Drozdova, O. A.,Astrat'ev, A. A.,Kuznetsov, L. L.,Selivanov, V. F.
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p. 671 - 675
(2007/10/02)
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- EFFECT OF STRUCTURE ON THE KINETICS AND MECHANISM OF THE ACID-CATALYZED DECOMPOSITION OF N-NITROBENZENESULFONAMIDES
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The decomposition rate of a series of ring-substituted N-nitrobenzenesulfonamides in aqueous sulfuric acid was measure by a spectrophotometric method.Decomposition of the compounds takes place both by the cleavage of the N-S bond to form the corresponding sulfonic acid, nitrous oxide, and water and by denitration.In crease in the electronegativity of the substituent in the aromatic ring promotes the denitration reaction.
- Drozdova, O. A.,Astrat'ev, A. A.,Kuznetsov, L. L.,Selivanov, V. F.
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p. 2063 - 2067
(2007/10/02)
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