104-15-4Relevant articles and documents
The mechanisms of acid-catalyzed hydrolysis of n-(4-substituted arylthio) phthalimides
Kutuk, Halil,Yakan, Hasan
, p. 1460 - 1469 (2011)
The acid-catalyzed hydrolysis of N-(4-substitutedarylthio)phthalimides was studied in aqueous solutions of sulfuric, perchloric, and hydrochloric acids at 40.0 ±0.1° C. Analysis of the data by the excess acidity method, activation parameters, and substituent effects indicates hydrolysis by an A-2 mechanism at low acidity. At higher acidities, a changeover to an A-1 mechanism is observed.
Effect of Amine Nature on Reaction Rate and Mechanism in Nucleophilic Substitution Reactions of 2,4-Dinitrophenyl X-Substituted Benzenesulfonates with Alicyclic Secondary Amines
Um, Ik-Hwan,Chun, Sun-Mee,Chae, Ok-Mi,Fujio, Mizue,Tsuno, Yuho
, p. 3166 - 3172 (2004)
Second-order rate constants have been measured for reactions of 2,4-dinitrophenyl X-substituted benzenesulfonates with a series of alicyclic secondary amines. The reaction proceeds through S-O and C-O bond fission pathways competitively. The S-O bond fission occurs more dominantly as the amine basicity increases and the substituent X in the sulfonyl moiety becomes more strongly electron withdrawing, indicating that the regioselectivity is governed by the amine basicity as well as the electronic nature of the substituent X. The S-O bond fission proceeds through an addition intermediate with a change in the rate-determining step at pKa° = 9.1. The secondary amines are more reactive than primary amines of similar basicity for the S-O bond fission. The k1 value has been determined to be larger for reactions with secondary amines than with primary amines of similar basicity, which fully accounts for their higher reactivity. The second-order rate constants for the S-O bond fission result in linear Yukawa-Tsuno plots while those for the C-O bond fission exhibit poor correlation with the electronic nature of the substituent X. The distance effect and the nature of reaction mechanism have been suggested to be responsible for the poor correlation for the C-O bond fission pathway.
Evidence for complexes of different stoichiometries between organic solvents and cyclodextrins
Garcia-Rio,Herves,Leis,Mejuto,Perez-Juste,Rodriguez-Dafonte
, p. 1038 - 1048 (2006)
The influence of the organic solvent on the acid and basic hydrolysis of N-methyl-N-nitroso-p-toluenesulfonamide (MNTS) in the presence of α- and β-cyclodextrins has been studied. The observed rate constant was found to decrease through the formation of an unreactive complex between MNTS and the cyclodextrins. In the presence of dioxane, acetonitrile or DMSO, the inhibitory effect of β-CD decreased on increasing the proportion of organic cosolvent as a result of a competitive reaction involving the formation of an inclusion complex between β-CD and the cosolvent. The disparate size of the organic solvent molecules resulted in stoichiometric differences between the complexes; the β-CD-dioxane and β-CD-DMSO complexes were 1: 1 whereas the β-CD-acetonitrile complex was 1: 2. The basic and acid hydrolysis of MNTS in the presence of α-CD showed a different behavior; thus, the reaction gave both 1: 1 and 2: 1 α-CD-MNTS complexes, of which only the former was reactive. This result was due to the smaller cavity size of α-CD and the consequent decreased penetration of MNTS into the cavity in comparison to β-CD. The acid hydrolysis of MNTS in the presence of α-CD also revealed decreased penetration of MNTS into the cyclodextrin cavity, as evidenced by the bound substrate undergoing acid hydrolysis. In addition, the acid hydrolysis of MNTS in the presence of acetonitrile containing α-CD gave 1: 1 α-CD-acetonitrile inclusion complexes, which is consistent with a both a reduced cavity size and previously reported data. The Royal Society of Chemistry 2006.
Removal of electrophilic potential genotoxic impurities using nucleophilic reactive resins
Lee, Claire,Helmy, Roy,Strulson, Christopher,Plewa, Jolanta,Kolodziej, Elizabeth,Antonucci, Vincent,Mao, Bing,Welch, Christopher J.,Ge, Zhihong,Al-Sayah, Mohammad A.
, p. 1021 - 1026 (2010)
Potential genotoxic impurities (PGI) are chemical compounds that could potentially damage DNA and lead to mutation. Controlling the occurrence of PGIs in active pharmaceutical ingredients (APIs) poses a big challenge for chemists, as levels of these compounds must be reduced well below the amounts required for other types of less toxic impurities. In situations where formation of PGIs cannot be avoided, an ideal solution would allow the complete removal of PGIs after the synthesis is complete, for example, by recrystallization, preparative chromatography or other downstream processing approaches. Some disadvantages of using these approaches are potential high yield loss, high solvent consumption, and additional time and resources required for process development. In this work, we present a simple and rapid approach to remove electrophilic PGIs from APIs. A selected nucleophilic resin can be added to the final API solution to reduce or totally remove the PGI. Esters of methanesulfonic acid (MSA), benzenesulfonic acid (BSA), and ρ-toluenesulfonic acid (pTSA) were used as model electrophilic PGIs. Several nucleophilic resins were screened, and the resins with the highest efficiency of PGI removal were chosen. A recommended procedure is presented for the removal of MSA, BSA, and pTSA esters. The kinetics of PGI removal, resin loading capacity, solvent effects, and API matrix effects are demonstrated.
ESR study of free radical decomposition of N,N-bis(arylsulfonyl)hydroxylamines in organic solution
Balakirev, Maxim Yu.,Khramtsov, Valery V.
, p. 7263 - 7269 (1996)
Decomposition of N,N-bis(p-tolylsulfonyl)hydroxylamine (BTH) in chloroform and benzene solutions has been studied and was found to involve the formation of several radical intermediates. This process has been found to be accelerated by oxygen, resulting in the formation of p-toluenesulfonic acid and N,N,O-tris(p-tolylsulfonyl)hydroxylamine (TTH) as the main decay products. In addition, a small amount of p-toluenesulfonyl chloride has been isolated from chloroform solution, suggesting the chlorine abstraction from solvent. The formation of nitric oxide (NO) from BTH has been shown by mass spectrometry in gaseous phase and using nitronyl nitroxide as an NO trap in solution. It was proposed that liberation of NO proceeds through the homolytic cleavage of the S-N bond of p-tolylsulfonyl nitrite existing in equilibrium with BTH in solution. The formation of p-tolylsulfonyl radicals has been proved by spin trapping using 2-methyl-2-nitrosopropane (MNP) and 5,5-dimethyl-1-pyrroline N-oxide (DMPO). The rate of NO production in the presence of nitronyl nitroxide and the rate of oxygen consumption revealed linear plots in BTH concentration with the rate constants 0.0044 s-1 and 0.0016 s-1, respectively. It was found also that nitrogen dioxide formed during NO oxidation reacts readily with BTH to produce the organic analog of Fremy's radical. This radical recombines with p-tolylsulfonyl radical yielding N,N,O-trisubstituted hydroxylamine TTH.
Investigation of micellar media containing ?2-cyclodextrins by means of reaction kinetics: Basic hydrolysis of N-methyl-N-nitroso-p-toluenesulfonamide
Garciì?a-Riì?o,Leis,Mejuto,Peì?rez-Juste
, p. 7383 - 7389 (1997)
The kinetics of the basic hydrolysis of N-methyl-N-nitroso-p-toluenesulfonamide were studied in media containing sodium dodecyl sulfate (SDS) or tetradecyltrimethylammonium bromide (TTABr) micelles and ?2-cyclodextrin (CD). Under the experimental conditions, [NaOH] = 0.17 M, all CD will have been deprotonated; thus, binding constants apply to the CD anion. The results have been interpreted in terms of a pseudophase model that takes into account the formation of both CD - surfactant and CD - substrate complexes and also, for TTABr systems, the exchange of Br- and OH- ions between the micellar and aqueous pseudophases. The presence of CD has no effect on existing SDS or TTABr micelles but raises the cmc: complexation of surfactant by cyclodextrin makes the cmc dependent on CD concentration because the cmc is now the sum of the concentrations of free and complexed surfactant when micelles begin to form; increasing [CD] reduces the former quantity but increases the latter to a greater extent. At surfactant concentrations above the cmc, competition between the micellization and complexation processes leads to the existence of a significant concentration of free cyclodextrin.
Hydrogenolysis of 2-tosyloxy-1,3-propanediol into 1,3-propanediol over Raney Ni catalyst
Zheng, Zhi,Wang, Jianli,Lu, Zhen,Luo, Min,Zhang, Miao,Xu, Lixin,Ji, Jianbing
, p. 385 - 391 (2013)
2-Tosyloxy-1,3-propanediol (TPD), a potential precursor for 1,3-propanediol (1,3-PD) production, is produced by the tosylation of glycerol with the help of protecting group techniques. In this work, the hydrogenolysis of TPD into 1,3-PD over Raney Ni catalyst is discussed at different reaction parameters to optimize the reaction conditions for selective formation of 1,3-PD. The mechanisms of the hydrogenolysis of TPD and the side reactions were also confirmed by gas chromatography-mass spectrometry (GC-MS) technique.
The quest for sulfoquinone imine intermediates in the reaction of sulfanilic acid derivatives with nucleophiles
Thea, Sergio,Vigo, Daniele,Cevasco, Giorgio
, p. 611 - 614 (2002)
Data from kinetic and trapping studies suggest that the alkaline hydrolyses of sulfanilyl chloride and of the corresponding N-acetyl derivative follow different reaction pathways. While results for the latter compound are fully consistent with the occurrence of the common associative, SN2 mechanism, the former shows somewhat different features suggesting the incursion of a mechanism of the dissociative type involving a sulfoquinone imine species as a reaction intermediate. The alkaline hydrolyses of the corresponding sulfonyl fluorides and 2,4-dinitrophenyl esters, whose leaving groups are worse than Cl- as leaving groups, are all associative.
Influence of colloid suspensions of humic acids on the alkaline hydrolysis of N-methyl-N-nitroso-p-toluene sulfonamide
Astray,Garcia-Rio,Lodeiro,Mejuto,Moldes,Morales,Moyano
, p. 316 - 322 (2010)
The influence of humic substances (HSs) upon the alkaline hydrolysis of N-methyl-N-nitroso-p-toluene sulfonamide has been studied. Important inhibition of hydrolysis reaction has been reported. This inhibition has been explained in terms of association of reactants to the humic substances. Kinetic results have been modeled using the micellar pseudophase model.
General, fast, and high yield oxidation of thiols and disulfides to sulfonic and sulfinic acids using HOF·CH3CN
Shefer, Neta,Carmeli, Mira,Rozen, Shlomo
, p. 8178 - 8181 (2007)
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.
