98-11-3

Basic information

• Product Name: Benzenesulfonic acid
• Synonyms: 17-120a;acidebenzenesulfonique;Benzenemonosulfonic acid;benzenemonosulfonicacid;Benzenesulfonicacid(40%solu;Besylic acid;besylicacid;Kyselina benzensulfonova
• CAS NO: 98-11-3
• Molecular Formula: C₆H₆O₃S
• Molecular Weight: 158.18
• EINECS: 202-638-7
• Product Categories: Intermediates of Dyes and Pigments;Organic AcidsOrganic Building Blocks;Sulfonic/Sulfinic Acids;Sulfur Compounds;Chemical Synthesis;Organic Acids;Synthetic Reagents
• Mol File: 98-11-3.mol
• Article Data: 120

Chemical Properties

• Melting Point: 30-60 °C
• Boiling Point: 137℃
• Flash Point: >230 °F
• Appearance: Yellow to light brown/Damp Crystalline Solid or Fused Mass
• Density: 1.32
• Vapor Pressure: 3.07E-08mmHg at 25°C
• Refractive Index: 1.5151 (estimate)
• Storage Temp.: Store below +30°C.
• Solubility: H2O: soluble0.1g/10 mL, clear, colorless
• PKA: 0.7(at 25℃)
• Water Solubility: soluble
• Sensitive: Hygroscopic
• Stability: Stable. Incompatible with strong oxidizing agents, bases, many organic compounds.
• Merck: 14,1070
• BRN: 742513
• CAS DataBase Reference: Benzenesulfonic acid(CAS DataBase Reference)
• NIST Chemistry Reference: Benzenesulfonic acid(98-11-3)
• EPA Substance Registry System: Benzenesulfonic acid(98-11-3)

Safety Data

• Hazard Codes: C
• Statements: 22-34
• Safety Statements: 26-36/37/39-45-36
• RIDADR: UN 2583 8/PG 2
• WGK Germany: 1
• RTECS: DB4200000
• TSCA: Yes
• HazardClass: 8
• PackingGroup: III
• Hazardous Substances Data: 98-11-3(Hazardous Substances Data)

Usage

Uses

Used in Pharmaceutical Industry:
Benzenesulfonic acid is used as a pharmaceutical agent for preparing various drugs as salts, known as besylates or besilates. These besylate salts are utilized in the formulation of medications due to their improved solubility and bioavailability.
Used in Chemical Production:
Benzenesulfonic acid is used in the production of phenol through a reaction involving its alkali metal salt. The process involves the conversion of benzene sulfonic acid to phenol and sodium sulfate, although this method has been largely replaced by the Hock process, which generates less waste.
Used in Supramolecular Chemistry:
Benzenesulfonic acid is used as an aryl sulfonic acid to form an organic salt with 5,7-dimethyl-1,8-naphthyridine-2-amine. This organic salt can act as a synthon for developing supramolecular structures, which have potential applications in various fields, including materials science and drug design.
Used in Conducting Polymers:
Benzenesulfonic acid can act as a dopant for the polymerization of pyrrole to form poly(pyrrole), a conducting polymer. This polymer is useful in the development of flexible capacitors and other electronic applications, contributing to advances in wearable technology and energy storage solutions.
Used as an Acid Catalyst:
Benzenesulfonic acid is utilized as an acid catalyst for the direct esterification of amino acids and peptides. This application is important in the synthesis of various bioactive compounds and pharmaceuticals, facilitating chemical reactions that would otherwise be slow or inefficient.

Preparation

Benzene sulfonic acid is prepared from the sulfonation of benzene using concentrated sulfuric acid : This conversion illustrates aromatic sulfonation, which has been called "one of the most important reactions in industrial organic chemistry.".

Reactions

Benzene sulfonic acid exhibits the reactions typical of other aromatic sulfonic acids, forming sulfonamides , sulfonyl chloride, and esters. The sulfonation is reversed above 220 °C. Dehydration with phosphorus pentoxide gives benzene sulfonic acid anhydride ((C6H5SO2)2O). Conversion to the corresponding benzene sulfonyl chloride (C6H5SO2Cl) is effected with phosphorus penta chloride. It is a strong acid, being dissociated in water.

Synthesis Reference(s)

The Journal of Organic Chemistry, 61, p. 1530, 1996 DOI: 10.1021/jo9520710Tetrahedron Letters, 19, p. 1211, 1978 DOI: 10.1016/S0040-4039(01)94501-0

Air & Water Reactions

Slightly soluble in water.

Reactivity Profile

Benzenesulfonic acid reacts with bases and many organic compounds.

Fire Hazard

Flash point data for Benzenesulfonic acid are not available, however Benzenesulfonic acid is probably combustible.

Flammability and Explosibility

Nonflammable

Safety Profile

Poison by ingestion, sbn contact, and probably inhalation. A severe skin and eye irritant. See also SULFATES and SULFONATES.

Purification Methods

Purify benzenesulfonic acid by dissolving it in a small volume of distilled H2O and stirring with slightly less than the theoretical amount of BaCO3. When effervescence is complete and the solution is still acidic, filter off the insoluble barium benzenesulfonate. The salt is collected and dried to constant weight in vacuo, then suspended in H2O and stirred with a little less than the equivalent (half mol.) of sulfuric acid. The insoluble BaSO4 (containing a little barium benzenesulfonate) is filtered off and the filtrate containing the free acid is evaporated in a high vacuum. The oily residue will eventually crystallise when completely anhydrous. A 32% commercial acid is allowed to fractionally crystallise at room temperature over P2O5 in a vacuum desiccator giving finally colourless deliquescent plates m 52.5o. The anhydrous crystalline acid is deliquescent and should be stored over anhydrous Na2SO4 in the dark and should be used in subdued sunlight as it darkens under sunlight. The main impurity is Fe which readily separates as the Fe salt in the early fractions [Taylor & Vincent J Chem Soc 3218 1952]. The S-benzylisothiuronium salt has m 148o (from EtOH/H2O). It is an IRRITANT to the skin and eyes. [See Adams & Marvel Org Synth Coll Vol I 84 1941, Michael & Adair Chem Ber 10 585 1877, Beilstein 11 IV 27.]

InChI:InChI=1/C6H6O3S.H2O/c7-10(8,9)6-4-2-1-3-5-6;/h1-5H,(H,7,8,9);1H2

Upstream product

• 56-23-5 tetrachloromethane 
• 39083-10-8 acetone oxime-o-benzenesulfonic ester 
• 7575-57-7 allyl benzenesulfonate 
• 93-59-4 Perbenzoic acid 
• 67-66-3 chloroform 
• 14758-47-5 tetrathioorthocarbonic acid tetraphenyl ester 
• 108-86-1 bromobenzene 
• 1212-08-4 S-Phenyl benzenethiosulfonate 
• 64-17-5 ethanol 
• 71-55-6 1,1,1-trichloroethane 
• 873-55-2 sodium benzenesulfonate 
• 13440-24-9 1,2-dibromo-1,2-diphenylethane 
• 65492-21-9 ((Iodomethyl)sulfonyl)benzene 
• 110-82-7 cyclohexane 

Downstream Products

• 98-55-5 terpineol 
• 29754-47-0 pyridinium para-toluene sulfonate 
• 2643-30-3 3-Vinylquinuclidine 
• 6667-90-9 (E)-3-ethylidenequinuclidine 
• 563-79-1 2,3-Dimethyl-2-butene 
• 558-37-2 tert-butylethylene 
• 563-78-0 2,3-Dimethyl-1-butene 
• 502-44-3 hexahydro-2H-oxepin-2-one 
• 108-05-4 vinyl acetate 
• 75-07-0 acetaldehyde 
• 100-47-0 benzonitrile 
• 141-78-6 ethyl acetate 
• 7785-53-7 4R-α-terpineol 
• 827-24-7 2-bromo-4-methyl-6-nitroaniline 

Relevant articles and documents

Spontaneous Oxidation of Aromatic Sulfones to Sulfonic Acids in Microdroplets

Reactions in microdroplets can be accelerated and can present unique chemistry compared to reactions in bulk solution. Here, we report the accelerated oxidation of aromatic sulfones to sulfonic acids in microdroplets under ambient conditions without the addition of acid, base, or catalyst. The experimental data suggest that the water radical cation, (H2O)+?, derived from traces of water in the solvent, is the oxidant. The substrate scope of the reaction indicates the need for a strong electron-donating group (e.g., p-hydroxyl) in the aromatic ring. An analogous oxidation is observed in an aromatic ketone with benzoic acid production. The shared mechanism is suggested to involve field-assisted ionization of water at the droplet/air interface, its reaction with the sulfone (M) to form the radical cation adduct, (M + H2O)+?, followed by 1,2-aryl migration and C-O cleavage. A remarkably high reaction rate acceleration (～103) and regioselectivity (～100-fold) characterize the reaction.

New insight into the electrochemical reduction of different aryldiazonium salts in aqueous solutions

Electrochemical reduction of different aryldiazonium salts in aqueous solution was studied in this work and it is shown that the aryldiazonium salts are converted to the corresponding aryl radical and aryl anion. The results of this research indicate that the reduction of aryldiazonium salts takes place in two single-electron steps. Our data show that when the substituted group on the phenyl ring is H, Cl, OH, NO2, OCH3or SO3?, the corresponding diazonium salt shows poor adsorption characteristics, but when the substituted group is methyl, the corresponding diazonium salt shows strong adsorption characteristics. In the latter case, the voltammogram exhibits three cathodic peaks. In addition, the effect of various substitutions on the aryldiazonium reduction was studied by Hammett's method. The data are show that with increasing electron withdrawing capacity of the substituent, the reduction of corresponding diazonium salt becomes easier.

Sustainable access to sulfonic acids from halides and thiourea dioxide with air

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.

Aryl and alkyl sulfonic acid compounds as well as construction method adopting inorganic sulfur salt and application

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.

Discovery of a Gut-Restricted JAK Inhibitor for the Treatment of Inflammatory Bowel Disease

To identify Janus kinase (JAK) inhibitors that selectively target gastrointestinal tissues with limited systemic exposures, a class of imidazopyrrolopyridines with a range of physical properties was prepared and evaluated. We identified compounds with low intrinsic permeability and determined a correlation between permeability and physicochemical properties, clogP and tPSA, for a subset of compounds. This low intrinsic permeability translated into compounds displaying high colonic exposure and low systemic exposure after oral dosing at 25 mg/kg in mouse. In a mouse PK/PD model, oral dosing of lead compound 2 demonstrated dose-dependent inhibition of pSTAT phosphorylation in colonic explants post-oral dose but low systemic exposure and no measurable systemic pharmacodynamic activity. We thus demonstrate the utility of JAK inhibitors with low intrinsic permeability as a feasible approach to develop gut-restricted, pharmacologically active molecules with a potential advantage over systemically available compounds that are limited by systemic on-target adverse events.

Bimolecular proximity of a ruthenium complex and methylene blue within an anionic porous coordination cage for enhancing photocatalytic activity

The charge repulsion between a catalyst and substrate will significantly reduce the contact occurring between them, resulting in low reactivity. Herein, we report an anionic porous coordination cage that is capable of encapsulating both a cationic catalyst and cationic substrate in its cavity at the same time. After encapsulating the [Ru(bpy)3]2+Cl2 (bpy = bipyridine) catalyst, the cage/catalyst composite serves as an active heterogeneous catalyst for the photo-degradation of methylene blue (MB). The highly negatively charged cavity of PCC-2 allows for the sequential encapsulation of the cationic methylene blue substrate and the Ru catalyst, which in turn significantly shortens the distance between them, yielding an increased possibility of MB degradation. Moreover, the encapsulated Ru catalyst dramatically outperformed its homogeneous counterpart in terms of overall degradation performance and recyclability.

Exogenous-oxidant-and catalyst-free electrochemical deoxygenative C2 sulfonylation of quinoline: N-oxides

An exogenous-oxidant-and catalyst-free electrochemical deoxygenative C2 sulfonylation reaction has been achieved. By employing quinoline N-oxides as the starting materials, the electrochemical C-H sulfonylation of electron-deficient quinolines was indirectly achieved at room temperature and a variety of sulfonylated quinoline derivatives were synthesized in modest to high yield with excellent regioselectivity. Notably, this protocol is the first example for synthesizing sulfonylated electron-deficient heteroarenes/arenes through electrochemistry.

Regioselective Sulfonation of Aromatic Compounds over 1,3-Disulfonic Acid Imidazolium Chloride under Aqueous Media

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.

Method for synthesizing p-nitrobenzenesulfonic

The invention relates to a method for synthesizing p-nitrobenzenesulfonic and belongs to the technical field of organic chemical synthesis. The method comprises the steps of subjecting benzene serving as the raw material and sulfuric acid to sulfonation to obtain benzenesulfonic acid; pumping chlorine into benzenesulfonic acid, adding deionized water and zinc dibutyl dithiocaarbamate, and stirring the mixture; adding nitric acid and acetic anhydride into the mixture for water-bath heating, and then performing cooling through ice water; slowly adding a sodium hydroxide solution dropwise into the cooled mixture, performing heating reflux after dropping reaction, cooling the mixture to the room temperature, and obtaining p-nitrobenzenesulfonic through separation, recovery and drying. The method has the advantages that the reaction time is shortened by 30% of time needed by a 3-nitrobenzene acid synthesis method, pollution cannot be produced during reaction, and operation steps are simple.

Synthetic method for 4-chloro-8-aminoquinoline

The invention relates to a synthetic method for 4-chloro-8-aminoquinoline, belonging to the technical field of organic chemical synthesis. The method comprises the following steps: firstly adding benzene into concentrated sulfuric acid and carrying out sulfonation so as to obtain benzene sulfonic acid, then subjecting benzene sulfonic acid to mixing with water, polyethylene glycol and nitric acid, carrying out heating and stirring with zinc chloride, then carrying out reaction with iron and hydrochloric acid under stirring, carrying out anaerobic fermentation and desulfurization, then subjecting obtained fermented substances and chloropropanol to mixing and stirring, and finally carrying out reduction reaction so as to obtain the 4-chloro-8-aminoquinoline. The invention has the following beneficial effects: the synthetic method provided by the invention has simple operation steps and mild reaction conditions, can generate strong fluorescent characteristic in application process of the 4-chloro-8-aminoquinoline at the same time, and can be applied in detection of the contents of metal ions.