Benzenesulfonic acid

Last updated
Benzenesulfonic acid [1]
Benzenesulfonic-acid-2D-skeletal.png
Benzenesulfonic acid molecule ball.png
Names
Preferred IUPAC name
Benzenesulfonic acid [2]
Other names
Benzene sulphonic acid; Benzenesulphonic acid; Phenylsulfonic acid; Phenylsulphonic acid; Besylic acid [3]
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.002.399 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 202-638-7
PubChem CID
RTECS number
  • DB4200000
UNII
UN number 2583, 2585, 1803
  • InChI=1S/C6H6O3S/c7-10(8,9)6-4-2-1-3-5-6/h1-5H,(H,7,8,9) Yes check.svgY
    Key: SRSXLGNVWSONIS-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C6H6O3S/c7-10(8,9)6-4-2-1-3-5-6/h1-5H,(H,7,8,9)
    Key: SRSXLGNVWSONIS-UHFFFAOYAJ
  • OS(=O)(=O)c1ccccc1
Properties
C6H6O3S
Molar mass 158.17 g·mol−1
AppearanceColorless crystalline solid
Density 1.32 g/cm3 (47 °C)
Melting point
  • 44 °C (hydrate)
  • 51 °C (anhydrous)
Boiling point 190 °C (374 °F; 463 K)
Soluble
Solubility in other solventsSoluble in alcohol, insoluble in non-polar solvents
Acidity (pKa)−2.8 [4]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Corrosive
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-exclam.svg
Danger
H290, H302, H314, H315, H319, H335
P234, P260, P261, P264, P270, P271, P280, P301+P312, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P330, P332+P313, P337+P313, P362, P363, P390, P403+P233, P404, P405, P501
Flash point > 113 °C
Safety data sheet (SDS) External MSDS
Related compounds
Related sulfonic acids
Sulfanilic acid
p-Toluenesulfonic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Benzenesulfonic acid (conjugate base benzenesulfonate) is an organosulfur compound with the formula C 6 H 6 O 3 S. It is the simplest aromatic sulfonic acid. It forms white deliquescent sheet crystals or a white waxy solid that is soluble in water and ethanol, slightly soluble in benzene and insoluble in nonpolar solvents like diethyl ether. It is often stored in the form of alkali metal salts. Its aqueous solution is strongly acidic.

Contents

Preparation

Benzenesulfonic acid is prepared from the sulfonation of benzene using concentrated sulfuric acid:

Synthesis Benzenesulfonic acid.svg

This conversion illustrates aromatic sulfonation, which has been called "one of the most important reactions in industrial organic chemistry". [5]

Reactions

Benzenesulfonic 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 benzenesulfonic acid anhydride ((C6H5SO2)2O). Conversion to the corresponding benzenesulfonyl chloride (C6H5SO2Cl) is effected with phosphorus pentachloride.

It is a strong acid, being almost fully dissociated in water.

Benzenesulfonic acid and related compounds undergo desulfonation when heated in water near 200 °C. The temperature of desulfonation correlates with the ease of the sulfonation: [5]

C6H5SO3H + H2O → C6H5OH + H2SO4

For that reason, sulfonic acids are usually used as a protecting group, or as a meta director in electrophilic aromatic substitution.

The alkali metal salt of benzenesulfonic acid was once used in the industrial production of phenol. The process, sometimes called alkaline fusion, initially affords the phenoxide salt:

C6H5SO3Na + 2 NaOH → C6H5ONa + Na2SO3
C6H5ONa + HCl → C6H5OH + NaCl

The process has been largely displaced by the Hock process, which generates less waste.

Uses

Salts of benzenesulfonic acid such as sodium benzenesulfonate (Ludigol) and monoethanolamine benzenesulfonate are used as surfactants in laundry detergent. [6]

A variety of pharmaceutical drugs are prepared as benzenesulfonate salts and are known as besilates (INN) or besylates (USAN).

Related Research Articles

<span class="mw-page-title-main">Benzoic acid</span> Organic compound (C6H5COOH)

Benzoic acid is a white solid organic compound with the formula C6H5COOH, whose structure consists of a benzene ring with a carboxyl substituent. The benzoyl group is often abbreviated "Bz", thus benzoic acid is also denoted as BzOH, since the benzoyl group has the formula –C6H5CO. It is the simplest aromatic carboxylic acid. The name is derived from gum benzoin, which was for a long time its only source.

<span class="mw-page-title-main">Carboxylic acid</span> Organic compound containing a –C(=O)OH group

In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group attached to an R-group. The general formula of a carboxylic acid is often written as R−COOH or R−CO2H, sometimes as R−C(O)OH with R referring to an organyl group, or hydrogen, or other groups. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion.

The Friedel–Crafts reactions are a set of reactions developed by Charles Friedel and James Crafts in 1877 to attach substituents to an aromatic ring. Friedel–Crafts reactions are of two main types: alkylation reactions and acylation reactions. Both proceed by electrophilic aromatic substitution.

<span class="mw-page-title-main">Sulfonate</span> Organosulfur compound of the form R–S(=O)2–O (charge –1)

In organosulfur chemistry, a sulfonate is a salt, anion or ester of a sulfonic acid. Its formula is R−S(=O)2−O, containing the functional group −S(=O)2−O, where R is typically an organyl group, amino group or a halogen atom. Sulfonates are the conjugate bases of sulfonic acids. Sulfonates are generally stable in water, non-oxidizing, and colorless. Many useful compounds and even some biochemicals feature sulfonates.

<span class="mw-page-title-main">Sulfonic acid</span> Organic compounds with the structure R−S(=O)2−OH

In organic chemistry, sulfonic acid refers to a member of the class of organosulfur compounds with the general formula R−S(=O)2−OH, where R is an organic alkyl or aryl group and the S(=O)2(OH) group a sulfonyl hydroxide. As a substituent, it is known as a sulfo group. A sulfonic acid can be thought of as sulfuric acid with one hydroxyl group replaced by an organic substituent. The parent compound is the parent sulfonic acid, HS(=O)2(OH), a tautomer of sulfurous acid, S(=O)(OH)2. Salts or esters of sulfonic acids are called sulfonates.

<span class="mw-page-title-main">Phosphonium</span> Family of polyatomic cations containing phosphorus

In chemistry, the term phosphonium describes polyatomic cations with the chemical formula PR+
4
. These cations have tetrahedral structures. The salts are generally colorless or take the color of the anions.

<span class="mw-page-title-main">Triphenylphosphine</span> Chemical compound

Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to PPh3 or Ph3P. It is versatile compound that is widely used as a reagent in organic synthesis and as a ligand for transition metal complexes, including ones that serve as catalysts in organometallic chemistry. PPh3 exists as relatively air stable, colorless crystals at room temperature. It dissolves in non-polar organic solvents such as benzene and diethyl ether.

<span class="mw-page-title-main">Aromatic sulfonation</span> Chemical reaction which replaces a hydrogen on an arene with sulfonic acid, –NH–SO3H

In organic chemistry, aromatic sulfonation is an reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid group. Together with nitration and chlorination, aromatic sulfonation is a widely used electrophilic aromatic substitutions. Aryl sulfonic acids are used as detergents, dye, and drugs.

<span class="mw-page-title-main">Diazonium compound</span> Group of organonitrogen compounds

Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group [R−N+≡N]X where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide. The parent compound where R is hydrogen, is diazenylium.

<i>p</i>-Toluenesulfonic acid Chemical compound

p-Toluenesulfonic acid (PTSA, pTSA, or pTsOH) or tosylic acid (TsOH) is an organic compound with the formula CH3C6H4SO3H. It is a white extremely hygroscopic solid that is soluble in water, alcohols, and other polar organic solvents. The CH3C6H4SO2 group is known as the tosyl group and is often abbreviated as Ts or Tos. Most often, TsOH refers to the monohydrate, TsOH.H2O.

In chemistry, a sulfonyl halide consists of a sulfonyl group singly bonded to a halogen atom. They have the general formula RSO2X, where X is a halogen. The stability of sulfonyl halides decreases in the order fluorides > chlorides > bromides > iodides, all four types being well known. The sulfonyl chlorides and fluorides are of dominant importance in this series.

<span class="mw-page-title-main">Hexafluorophosphate</span> Anion with the chemical formula PF6–

Hexafluorophosphate is an anion with chemical formula of [PF6]. It is an octahedral species that imparts no color to its salts. [PF6] is isoelectronic with sulfur hexafluoride, SF6, and the hexafluorosilicate dianion, [SiF6]2−, and hexafluoroantimonate [SbF6]. In this anion, phosphorus has a valence of 5. Being poorly nucleophilic, hexafluorophosphate is classified as a non-coordinating anion.

<span class="mw-page-title-main">Hexachlorocyclohexa-2,5-dien-1-one</span> Chemical compound

Hexachlorocyclohexa-2,5-dien-1-one, sometimes informally called hexachlorophenol (HCP), is an organochlorine compound. It can be prepared from phenol. Despite the informal name, the compound is not a phenol but is a ketone. The informal name is derived from its method of preparation which includes phenol as a reagent.

<span class="mw-page-title-main">Methanesulfonic acid</span> Organosulfur compound (CHSO₂OH)

Methanesulfonic acid or methanesulphonic acid is an organosulfuric, colorless liquid with the molecular formula CH3SO3H and structure H3CS(=O)2−OH. It is the simplest of the alkylsulfonic acids. Salts and esters of methanesulfonic acid are known as mesylates. It is hygroscopic in its concentrated form. Methanesulfonic acid can dissolve a wide range of metal salts, many of them in significantly higher concentrations than in hydrochloric acid (HCl) or sulfuric acid.

Electrophilic aromatic substitution (SEAr) is an organic reaction in which an atom that is attached to an aromatic system is replaced by an electrophile. Some of the most important electrophilic aromatic substitutions are aromatic nitration, aromatic halogenation, aromatic sulfonation, alkylation Friedel–Crafts reaction and acylation Friedel–Crafts reaction.

<span class="mw-page-title-main">Diphenyl sulfone</span> Chemical compound

Diphenyl sulfone is an organosulfur compound with the formula (C6H5)2SO2. It is a white solid that is soluble in organic solvents. It is used as a high temperature solvent. Such high temperature solvents are useful for processing highly rigid polymers, e.g., PEEK, which only dissolve in very hot solvents.

<span class="mw-page-title-main">Benzenesulfonyl chloride</span> Chemical compound

Benzenesulfonyl chloride is an organosulfur compound with the formula C6H5SO2Cl. It is a colourless viscous oil that dissolves in organic solvents, but reacts with compounds containing reactive N-H and O-H bonds. It is mainly used to prepare sulfonamides and sulfonate esters by reactions with amines and alcohols, respectively. The closely related compound toluenesulfonyl chloride is often preferred analogue because it is a solid at room temperature and easier to handle.

Hydroxylamine-<i>O</i>-sulfonic acid Chemical compound

Hydroxylamine-O-sulfonic acid (HOSA) or aminosulfuric acid is the inorganic compound with molecular formula H3NO4S that is formed by the sulfonation of hydroxylamine with oleum. It is a white, water-soluble and hygroscopic, solid, commonly represented by the condensed structural formula H2NOSO3H, though it actually exists as a zwitterion and thus is more accurately represented as +H3NOSO3. It is used as a reagent for the introduction of amine groups (–NH2), for the conversion of aldehydes into nitriles and alicyclic ketones into lactams (cyclic amides), and for the synthesis of variety of nitrogen-containing heterocycles.

1,4-butane sultone is a six-membered δ-sultone and the cyclic ester of 4-hydroxybutanesulfonic acid. As a sulfo-alkylating agent, 1,4-butanesultone is used to introduce the sulfobutyl group (–(CH2)4–SO3) into hydrophobic compounds possessing nucleophilic functional groups, for example hydroxy groups (as in the case of β-cyclodextrin) or amino groups (as in the case of polymethine dyes). In such, the sulfobutyl group is present as neutral sodium salt and considerably increases the water solubility of the derivatives.

<span class="mw-page-title-main">Desulfonation reaction</span>

In organic chemistry, the desulfonation reaction is the hydrolysis of sulfonic acids:

References

  1. Benzenesulfonic acid [ dead link ], Sigma-Aldrich
  2. Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 789. doi:10.1039/9781849733069-FP001. ISBN   978-0-85404-182-4.
  3. Besylic acid, ChemIndustry
  4. Guthrie, J. P. Hydrolysis of esters of oxy acids: pKa values for strong acids Can. J. Chem. 1978, 56, 2342-2354. doi:10.1139/v78-385
  5. 1 2 Otto Lindner; Lars Rodefeld (2005). "Benzenesulfonic Acids and Their Derivatives". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a03_507. ISBN   978-3527306732.
  6. "Safety Data Sheet - P & G's Tide Simply" (PDF). pg.com. 2014-02-05. Retrieved 2018-04-13.