cas 98-58-8, 4-Bromobenzenesulfonyl chloride

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Copper-Catalyzed N-Directed Distal C(sp3)-H Sulfonylation and Thiolation with Sulfinate Salts
We herein report a selective and catalytic C(sp3)-H functionalization approach to access amines bearing organo-sulfonyl and organo-thiol groups. This reaction proceeds through a cascade process of N-radical formation, alkyl radical formation via 1,5-HAT, and C-S bond formation, thereby offering a series of functionalized amines. This method could enable primary, secondary, and tertiary C(sp3)-H sulfonylation and thiolation and also exhibits good functional group tolerance.
Chen, Guang-Le,He, Shi-Hui,Cheng, Liang,Liu, Feng
supporting information
p. 8338 - 8342
(2021/10/25)

Method for rapidly preparing N-benzenesulfonyl amino acid ester compound
The invention discloses a method for rapidly preparing an N-benzenesulfonyl amino acid ester compound. The invention mainly relates to chemical synthesis. A two-step one-pot strategy is adopted, substituted phenylmercaptan is used as a raw material, in-situ generated benzenesulfonyl chloride acts with hydrochloride of amino acid ester to obtain the N-benzenesulfonyl amino acid ester compound, the strategy is mild in condition, high in yield and high in reaction efficiency, and can be used for rapidly preparing the formula (I) compound and derivatives or analogues thereof. The method for rapidly preparing the N-benzenesulfonyl amino acid ester compound is simple to operate, mild in condition, high in yield and efficiency and relatively high in application value.
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Paragraph 0017

(2021/05/12)

Chromoselective Synthesis of Sulfonyl Chlorides and Sulfonamides with Potassium Poly(heptazine imide) Photocatalyst
Among external stimuli used to promote a chemical reaction, photocatalysis possesses a unique one—light. Photons are traceless reagents that provide an exclusive opportunity to alter chemoselectivity of the photocatalytic reaction varying the color of incident light. This strategy may be implemented by using a sensitizer capable to activate a specific reaction pathway depending on the excitation light. Herein, we use potassium poly(heptazine imide) (K-PHI), a type of carbon nitride, to generate selectively three different products from S-arylthioacetates simply varying the excitation light and otherwise identical conditions. Namely, arylchlorides are produced under UV/purple, sulfonyl chlorides with blue/white, and diaryldisulfides at green to red light. A combination of the negatively charged polyanion, highly positive potential of the valence band, presence of intraband states, ability to sensitize singlet oxygen, and multi-electron transfer is shown to enable this chromoselective conversion of thioacetates.
Antonietti, Markus,Guldi, Dirk M.,Markushyna, Yevheniia,Savateev, Aleksandr,Schü?lbauer, Christoph M.,Ullrich, Tobias
supporting information
p. 20543 - 20550
(2021/08/12)

Facile synthesis of sulfonyl chlorides/bromides from sulfonyl hydrazides
A simple and rapid method for efficient synthesis of sulfonyl chlorides/bromides from sulfonyl hydrazide with NXS (X = Cl or Br) and late-stage conversion to several other functional groups was described. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides and sulfonates. In most cases, these reactions are highly selective, simple, and clean, affording products at excellent yields.
Chen, Rongxiang,Xu, Shaohong,Shen, Fumin,Xu, Canran,Wang, Kaikai,Wang, Zhanyong,Liu, Lantao
(2021/09/20)

NOVEL COMPOUND, PREPARATION METHOD THEREOF, AND USE THEREOF
The present invention relates to a method for preparing a biomaterial having selectively functionalized tyrosine, a biomaterial having selectively functionalized tyrosine, and a pharmaceutical composition containing the same as an active ingredient. The method for preparing a biomaterial to which a compound represented by formula 2 is coupled, of the present invention, allows the compound represented by formula 2 to be selectively coupled, in a high yield in a biomaterial, to tyrosine, which is present on the surface of an aqueous solution such that the coupling thereof to amino acids other than tyrosine does not occur and, when only one tyrosine is present, heterogeneous mixtures are not present and the inherent activity of the biomaterial is maintained, and thus the compound can be effectively used as a pharmaceutical composition containing a biomaterial drug as an active ingredient. In addition, the method can selectively functionalize tyrosine, and thus can be effectively used for tyrosine functionalization in a biomaterial.
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Paragraph 530-534

(2021/07/24)

High yielding protocol for direct conversion of thiols to sulfonyl chlorides and sulfonamides
In this paper, a new method for oxidative chlorination of thiols to sulfonyl chlorides and sulfonamides using H2O2 in the presence of TMSCl is reported. The excellent yields, short reaction times, excellent efficiencies, low costs, and easy separation of products are the most important advantages of this method.
Sohrabnezhad, Samira,Bahrami, Kiumars,Hakimpoor, Farahman
p. 256 - 264
(2019/02/06)

A facile method for regioselective synthesis of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives via N-acetyl/thioacetyl sulfonamide formation
A series of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives were synthesized regioselectively in moderate to high yields by following a convenient, three-step procedure. The procedure consists of the direct oxidative conversion of a thiol compound to the corresponding sulfonyl chloride using TMSCl/KNO3, followed by a room temperature reaction in a one-pot transformation of the resultant sulfonyl chloride into N-acetyl/thioacetyl sulfonamide, which undergoes a further Pd-catalyzed coupling reaction, giving rise to the stilbene compounds reported for the first time.
Ahmadian-Moghaddam, Maryam,Bekhradnia, Ahmadreza,Tatar, Monire
supporting information
p. 481 - 484
(2017/05/01)

NOVEL COMPOUNDS AS GPR119 AGONISTS
The present invention relates to novel compounds of formula (I) as GPR119 agonist, composition compositions containing such compounds and method of preparation thereof.
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Paragraph 0427-0429

(2017/10/26)

Aromatic Chlorosulfonylation by Photoredox Catalysis
Visible-light photoredox catalysis enables the efficient synthesis of arenesulfonyl chlorides from anilines. The new protocol involves the convenient in situ preparation of arenediazonium salts (from anilines) and the reactive gases SO2and HCl (from aqueous SOCl2). The photocatalytic chlorosulfonylation operates at mild conditions (room temperature, acetonitrile/water) with low catalyst loading. Various functional groups are tolerated (e.g., halides, azides, nitro groups, CF3, SF5, esters, heteroarenes). Theoretical and experimental studies support a photoredox-catalysis mechanism.
Májek, Michal,Neumeier, Michael,Jacobi von Wangelin, Axel
p. 151 - 155
(2017/01/17)

Aminoxidation of Arenethiols to N-Chloro-N-sulfonyl Sulfinamides
A simple and efficient method to synthesize N-chloro-N-sulfonylsulfinamides by the direct aminoxidation of arenethiols under aqueous and mild conditions is disclosed, geminally installing the oxo and amino groups on the sulfur atom of arenethiols. The products have been primarily developed as sulfinylation reagents to convert Grignard reagents into sulfoxides, and as amination reagents to convert secondary amines into hydrazine derivatives.
Yang, Zhanhui,Xu, Wei,Wu, Qiuyue,Xu, Jiaxi
p. 3051 - 3057
(2016/04/26)

Synthesis and characterization of a mesogen-jacketed polyelectrolyte
In an attempt to construct a new kind of rodlike polyelectrolyte, poly[sodium 2,5-bis(4′-sulfophenyl)styrene] (PSBSS) was prepared from its precursor, poly[2,5-bis(4′-neopentylsulfophenyl)styrene] (PBNSS), which was polymerized by atom transfer radical polymerization. Small-angle X-ray scattering (SAXS) results demonstrate that PBNSS exhibits a hexagonal columnar phase and PSBSS exhibits a smectic A phase in bulk. The conformation of PSBSS in the aqueous solution is cylindrical, and the length and the diameter of the cylinder are ca. 25 nm and ca. 2.4 nm, respectively. The persistence length (lp) of the PSBSS chain in the aqueous solution is 11.50 ± 0.09 nm calculated by fitting the SAXS profile with the modified wormlike chain model. The conformation, the maximum length, and the lp of the chain are only weakly dependent on the concentration of the added salt. These results indicate that we have successfully obtained a new kind of polyelectrolyte with a highly rigid chain, a high charge density, and a narrow molecular weight distribution, which can serve as a new model macromolecule in studying rodlike polyelectrolytes.
Qu, Wei,Zhu, Xingqi,Chen, Jiahui,Niu, Lin,Liang, Dehai,Fan, Xinghe,Shen, Zhihao,Zhou, Qifeng
p. 2727 - 2735
(2014/05/06)

One-pot synthesis of sulfonamides and sulfonyl azides from thiols using chloramine-T
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine-T (=N-chlorotosylamide=N-chloro-4- methylbenzenesulfonamide), tetrabutylammonium chloride (Bu4NCl), and H2O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN3 in the same pot.
Maleki, Behrooz,Hemmati, Saba,Tayebee, Reza,Salemi, Sirous,Farokhzad, Yasaman,Baghayeri, Mehdi,Zonoz, Farrokhzad Mohammadi,Akbarzadeh, Elahe,Moradi, Rohollah,Entezari, Azam,Abdi, Mohammad Reza,Ashrafi, Samaneh Sedigh,Taimazi, Fereshteh,Hashemi, Majid
p. 2147 - 2151
(2013/12/04)

One-pot synthesis of 6-bromo-4,4-dimethylthiochroman
One-pot synthesis of 6-bromo-4,4-dimethylthiochroman from bromobenzene is reported. The crucial connection between the three steps is that the byproducts in the first two steps are used as the catalyst in the third step. Compared with the previous route, this approach is of low consumption and low pollution.
Zhou, Shaodong,Liao, Zutai,Yuan, Jixin,Qian, Chao,Chen, Xinzhi
p. 4121 - 4125
(2013/11/19)

Synthesis of sulfonyl chlorides and thiosulfonates from H2O 2-TiCl4
A new method is described for the oxidative chlorination of thiols to sulfonyl chlorides using titanium tetrachloride in combination with the oxidant hydrogen peroxide. Direct conversion of thiols into their corresponding thiosulfonates is also reported. Good to excellent yields, short reaction times, high efficiencies, cost-effectiveness, and, facile isolation of the desired products make the present methodology a practical alternative.
Bahrami, Kiumars,Khodaei, Mohammad M.,Khaledian, Donya
experimental part
p. 354 - 358
(2012/01/19)

Convenient one-pot synthesis of sulfonamides from thiols and disulfides using 1,3-dichloro-5,5-dimethylhydantoin (DCH)
A convenient synthesis of sulfonamides from thiols and disulfides is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with 1,3-dichloro-5,5-dimethylhydantoin (DCH) under Nbenzyl-trimethylammonium chloride and water. The sulfonyl chlorides are then further allowed to react with excess amine in the same reaction vessel.
Veisi, Hojat
experimental part
p. 383 - 386
(2012/04/23)

Synthesis of sulfonamides and sulfonic esters via reaction of amines and phenols with thiols using H2O2-POCl3 system
Phosphorus oxychloride efficiently promoted the synthesis of sulfonamides and sulfonic esters from thiols with hydrogen peroxide in the presence of Amberlite IRA-400 (OH-). This method has been applied to a variety of substrates including nucleophilic and sterically hindered amines, and also phenols with excellent yields of sulfonamides and sulfonic esters. In most cases these reactions are highly selective, simple, and clean, affording products in excellent yields and high purity.
Bahrami, Kiumars,Khodaei, Mohammad M.,Abbasi, Jamshid
supporting information; experimental part
p. 5095 - 5101
(2012/07/28)

Convenient one-pot synthesis of sulfonamides and sulfonyl azides from thiols using N -chlorosuccinimide
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with N-chlorosuccinimide (NCS), tetrabutylammonium chloride, and water. The sulfonyl chlorides are then further allowed to react with excess amine or sodium azide in the same reaction vessel. Georg Thieme Verlag Stuttgart - New York.
Veisi, Hojat,Ghorbani-Vaghei, Ramin,Hemmati, Saba,Mahmoodi, Jafar
experimental part
p. 2315 - 2320
(2011/10/13)

A convenient, one-pot procedure for the preparation of acyl and sulfonyl fluorides using Cl3CCN, Ph3P, and TBAF(t -BuOH) 4
Various carboxylic acids were converted into acyl fluorides in excellent yields by treatment with trichloroacetonitrile, triphenylphosphine, and TBAF(t-BuOH)4 at room temperature. The reaction was applicable to the preparation of acid-sensitive amino acid fluorides without deprotection or rearrangement
Kim, Joong-Gon,Jang, Doo Ok
experimental part
p. 3049 - 3052
(2011/02/25)

A novel, practical synthesis of sulfonyl chlorides from thiol and disulfide derivatives
Hydrogen peroxide, in the presence of zirconium tetrachloride, is a very efficient reagent for the direct oxidative conversion of thiol and disulfide derivatives into the corresponding sulfonyl chlorides with high purity through oxidative chlorination. Excellent yields, very short reaction times, mild reaction conditions, and the avoidance of harsh reagents are the main advantages of this method.
Bahrami, Kiumars,Khodaei, Mohammad Mehdi,Soheilizad, Mehdi
experimental part
p. 2773 - 2776
(2010/02/28)

Direct conversion of thiols to sulfonyl chlorides and sulfonamides
(Chemical Equation Presented) H2O2 in combination with SOCl2 proved to be a highly reactive reagent for the direct oxidative conversion of thiol derivatives to the corresponding sulfonyl chlorides with high purity through oxidative chlorination. Upon reaction with amines, the corresponding sulfonamides were obtained in excellent yields and in very short reaction times.
Bahrami, Kiumars,Khodaei, Mohammad M.,Soheilizad, Mehdi
supporting information; experimental part
p. 9287 - 9291
(2010/03/04)

Chlorotrimethylsilane-nitrate salts as oxidants: Direct oxidative conversion of thiols and disulfides to sulfonyl chlorides
(Chemical Equation Presented) A mixture of nitrate salt and chlorotrimethylsilane is found to be a mild and efficient reagent for the direct oxidative conversion of thiols (1) and disulfides (2) to the corresponding sulfonyl chlorides (3) in excellent yields through oxidative chlorination. Sulfides and sulfoxides were also found to undergo oxidation to sulfones under similar reaction conditions. In most cases these reactions are highly selective, simple, and clean, affording products in high yield and purity.
Prakash, G. K. Surya,Mathew, Thomas,Panja, Chiradeep,Olah, George A.
p. 5847 - 5850
(2008/02/09)

Reaction of arendiazonium salts and SO2with α-nitroolefins
In reaction of β-nitrostyrene and 2-(2-nitrovinyl)furan with arenediazonium chlorides and SO2 in the presence of copper(II) chloride products were obtained resulting from addition of arylsulfonyl group and a hydrogen atom across the C=C bond: 2-nitro-1-phenylethylsulfonylarenes and 2-(1-arylsulfonyl-2-nitroethyl)furans respectively. An anion-radical mechanism of the reaction was suggested.
Bilaya,Obushak,Buchinskii,Ganushchak
p. 191 - 194
(2007/10/03)

5-N-Substituted-2-(substituted benzenesulphonyl) glutamines as antitumor agents. Part II: Synthesis, biological activity and QSAR study
Cancer is a major killer disease throughout human history. Thus, cancer becomes a major point of interest in life science. It was proved that cancer is a nitrogen trap and tumor cells are avid glutamine consumers. The non-essential amino acid glutamine, which is a glutamic acid derivative, supplies its amide nitrogen to tumor cells in the biosynthesis of purine and pyrimidine bases of nucleic acids as well as takes part in protein synthesis. Based on these and in continuation of our composite programme of development of new potential anticancer agents through rational drug design, 17 new 5-N-Substituted-2- (substituted benzenesulphonyl) glutamines were selected for synthesis. These compounds as well as 36 earlier synthesized glutamine analogues were screened for antitumor activity using percentage inhibition of tumor cell count as the activity parameter. QSAR study was performed with 53 compounds in order to design leads with increased effectiveness for antitumor activity using both physicochemical and topological parameters. QSAR study showed that steric effect on the aromatic ring is conducive to the activity. n-butyl substitution on aliphatic side chain and atom no 12 is important for antitumor activity of glutamine analogues.
Samanta, Soma,Srikanth,Banerjee, Suchandra,Debnath, Bikash,Gayen, Shovanlal,Jha, Tarun
p. 1413 - 1423
(2007/10/03)

Facile one-pot synthesis of aromatic and heteroaromatic sulfonamides
A series of arene and heteroarene sulfonamides were prepared in one vessel from aryl and heteroaryl bromides via conversion into the corresponding Grignard reagents using either magnesium or isopropylmagnesium chloride and subsequent reaction with sulfur dioxide, sulfuryl chloride, and an amine.
Pandya, Rina,Murashima, Takashi,Tedeschi, Livio,Barrett, Anthony G. M.
p. 8274 - 8276
(2007/10/03)

CARBAMATE DERIVATIVES, PROCESS FOR PRODUCING THE SAME AND USE THEREOF
Novel carbamate derivatives which are useful as drugs because of inhibiting activated blood coagulation factor X and thus exerting an anticoagulant effect. Compounds represented by the formula: wherein R1 represents a group represented by the formula: (wherein Y1 represents CH=CH, etc.), which may be substituted, etc.; the ring A represents an oxo-substituted nitrogen-containing heterocyclic ring which may be further substituted; R2 represents a hydrogen atom, optionally substituted C1-4 alkyl, etc.; R3 represents optionally substituted C1-4 alkyl, etc.; and Z represents an optionally substituted nitrogen containing heterocyclic group, etc., or salts thereof.
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(2008/06/13)

Polymer electrolyte and process for producing the same
A polymer electrolyte having, in a main chain, a structural unit represented by the following formula (1):-[Ar1-(SO2-N-(X+)-SO2-Ar2)m-SO2-N-(X+)-SO2-Ar1-O]- wherein Ar1 and Ar2 independently represent a divalent aromatic groups, m represents an integer of 0 to 3, and X+ represents an ion selected from hydrogen ion, an alkali metal ion and ammonium ion, which is excellent in proton conductivity, thermal resistance and strength. The polymer electrolyte is soluble in solvents and has excellent film forming property and recycling efficiency.
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(2008/06/13)

Remarkably Mild and Simple Preparations of Sulfinates, Sulfonyl Chlorides and Sulfonamides from Thioanisoles
New and high yielding procedures to convert thioanisoles into versatile sulfonyl chloride derivatives were developed by strategically taking advantage of the Pummerer reaction.
De Vleeschauwer, Marc,Gauthier, Jacques Yves
p. 375 - 377
(2007/10/03)

Effects of medium and substituents on dissociation of 4,4′-disubstituted bis(benzenesulfon)imides
Ten 4,4′-disubstituted bis(arenesulfon)imides of the general formula XC6H4SO2NHSO2C6H 4X have been synthesized and their structures confirmed by their 1H NMR spectra. Elemental analyses are presented for the compounds not yet described. The dissociation constants of these model substances have been measured potentiometrically in pyridine, dimethylformamide, methanol, ethanol, propylene carbonate, acetone, acetonitrile, 1,2-dichloroethane and tetramethylene sulfone. The pKHA values obtained have been correlated with three sets of the Hammett substituent constants and the results have been used to discuss the solvent and substituent effects on the dissociation of the compounds studied. Sulfonimides with electron-acceptor substituents behave as rather strong acids in some solvents (pyridine, dimethylformamide, methanol and ethanol), whereas normal substituent dependences are found in other solvents. The experimental data have also been interpreted with the help of the statistical methods based on latent variables. From the calculations it follows that only the first principal component, which correlates well with the substituent constant sets adopted, is statistically significant in describing the substituent effect on the acid-base process studied.
Ludwig, Miroslav,Stverka, Pavel
p. 1205 - 1214
(2007/10/03)

Convenient One-Pot Synthesis of Sulfonyl Chlorides from Thiols Using Sulfuryl Chloride and Metal Nitrate
Various sulfonyl chlorides were obtained in excellent yields by the reaction of alkyl and aryl thiols with sulfuryl chloride in the presence of metal nitrate under mild condition in aprotic solvents such as acetonitrile and N,N-dimethylformamide.
Park, Young Jun,Shin, Hyun Ho,Kim, Yong Hae
p. 1483 - 1486
(2007/10/02)

A new and facile synthesis of sulfonyl chlorides
Several benzenesulfonyl and arylmethanesulfonyl chlorides 2 are synthesized in excellent yields by the aqueous chlorination of aryl (or benzyl) methoxymethyl sulfides 1. Functionalized sulfides 1 d-g can be prepared easily from bromophenyl methoxymethyl sulfides 1b,c.
Kim,Ko,Kim
p. 1203 - 1204
(2007/10/02)

Multiple Structure-Reactivity Relationships for a Menschutkin-type SN2 Reaction
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
p. 7 - 14
(2007/10/02)

Influence of Pressure on the Menschutkin-Type Reaction of Phenethyl Arenesulfonates with Pyridine
Kinetic investigation of β-phenethyl arenesulfonates with pyridine in acetonitrile revealed that the rates of these reactions which were lower than those of the reaction of benzyl benzenesulfonate with pyridine in acetone were increased with raising temperatures and pressures.The activation volumes were comparable to those of benzyl system, but the activation entropies were negatively larger than those of benzyl system.From these phenomena it can be deduced that phenethyl system has more SN2 character in the transition state, comparing with the reaction of benzyl system.With raising pressures the Hammett reaction parameters (ρ) were decreased, indicating that the reaction is probably closer to the tihgt SN2 character at higher pressures.
Yoh, Soo-Dong,Park, Jong-Hwan,Lee, Kyung-A,Han, In-Sook
p. 1149 - 1152
(2007/10/02)

An Improved Synthesis of Arylsulfonyl Chlorides from Aryl Halides
Arylsulfonyl chlorides 8 are prepared from aryl bromides 5 via lithium arylsulfinates 7 in excellent yields.
Hamada, Tatsuo,Yonemitsu, Osamu
p. 852 - 854
(2007/10/02)

DISSOCIATION OF SUBSTITUTED BENZENESULPHONAMIDES IN WATER, METHANOL AND ETHANOL
Thirteen monosubstituted arylsulphonamides (XC6H4SO2NH2) and two 3,4-disubstituted arylsulphonamides (X2C6H3SO2NH2) have been synthetized and their dissociation constants have been measured by potentiometric titration in water, methanol, and ethanol.The Hammett substitution dependences have been calculated for all the media, and changes in the reaction constants due to transition from water to alcohols are discussed in confrontation with analogous dependences of benzoic acids.The reaction constant ρ found in methanol is lower than that in water.The dissociation constants have been treated by the method of the principal components and by multiple linear regression.
Ludwig, Miroslav,Pytela, Oldrich,Kalfus, Karel,Vecera, Miroslav
p. 1182 - 1192
(2007/10/02)

Electrophilic Aromatic Substitution. Part 33. Partial Rate Factors for Protiodetritiation of Benzothiophen; the Resonance-dependent Reactivity of the Ring Positions
Rate coefficients for detriation of benzothiophen, specifically labelled with tritium at each position, have been measured in anhydrous trifluoroacetic acid, and, for benzothiophen, in a range of trifluoroacetic acid-acetic acid mixtures, all at 70 deg C.The dependence of rate upon acidity is consistent with the effect of hydrogen bonding between sulphur and trifluoroacetic acid, as found previously for other sulphur-containing heterocycles.Partial rate factors, corrected for the effect of hydrogen bonding are (positions in parentheses): 8.84 * 105 (2); 1.18 * 106 (3); 360 (4); 13200 (5); 16200 (6); and 26.2 (7); the corresponding ?+ values are -0.68, -0.695, -0.29, -0.47, -0.48, and -0.16.The positional reactivity order is the same as found in pyrolysis of 1-arylethyl acetates, and solvolysis of 1-arylethyl chlorides, but the ?+ values are more negative due to the greater demand for resonance stabilization of the transition states in hydrogen exchange.Comparison of the 2- : 3-isomer ratios in various substitutions leads to the unexpected conclusion that substitution at the 2-position is subject to steric effects, probably due to the proximity of the sulphur d-orbitals.
Amin, Hassan B.,Awad, Amin A.,Archer, William J.,Taylor, Roger
p. 1489 - 1492
(2007/10/02)

Method of producing quaternary pyridinium compounds
The method of preparing quaternary pyridinium compounds having the formula STR1 WHEREIN R represents alkyl, STR2 in which A is phenyl, naphthyl, carbostyrilyl, pyrazolinyl and substituted derivatives thereof where the substitutents are selected from the group consisting of alkyl having 1 to 4 carbon atoms, NO2, Cl, Br, phenyl, nitrophenyl and methylsulfonate; B is -O-alkylene-, STR3 AND C is selected from the group consisting of hydrogen, NHCOR1 and, when B is -O-alkylene, C can also be --OR2 -- where R1 is alkyl of 1 to 4 carbon atoms and R2 is alkylene of 1 to 4 carbon atoms; and wherein R4 represents lower alkyl having 1 to 6 carbon atoms, halophenyl, alkylphenyl or naphthyl, m represents an integer of 1 or 2 and m' is equal to m. The process for preparing the particularly designated compounds above comprises contacting pyridine and a hydroxy-containing compound having the formula: R'--(OH)n wherein R' represents alkyl, STR4 in which A' is phenyl, naphthyl, carbostyrilyl, pyrazolinyl and substituted derivatives thereof where the substituents are selected from the group consisting of alkyl having 1 to 4 carbon atoms, NO2, Cl, Br, phenyl, nitrophenyl and hydroxy; B, C, R1 and R2 are as defined above; and n is an integer of 1 or 2 and is equivalent to m defined above; reacting the pyridine and said hydroxy-containing compound in the presence of a sulfonyl halide having the formula R4 SO2 X wherein R4 is as defined above and X is Cl, Br or F; and conducting the reaction at an elevated temperature up to the reflux temperature of the reaction mixture. The quaternary pyridinium compounds can be used to prepare cationic surfactants, cationic pharmaceuticals, cationic dyestuffs, pesticides, fungicides and agricultural chemicals.
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(2008/06/13)