24447-99-2

Basic information

• Product Name: N-METHYLANILINE-P-SULFONIC ACID
• Synonyms: N-METHYLAMINOBENZENE-P-SULFONIC ACID;N-METHYLANILINE-P-SULFONIC ACID;N-METHYLSULFANILIC ACID;N-METHYLSULPHANILIC ACID;ANILINOMETHANE-P-SULFONIC ACID;4-(methylamino)benzenesulphonic acid;4-methylaminobenzenesulfonic acid;N-Methylsulfanilic acid, 98+%
• CAS NO: 24447-99-2
• Molecular Formula: C₇H₉NO₃S
• Molecular Weight: 187.22
• EINECS: 246-256-9
• Mol File: 24447-99-2.mol

Chemical Properties

• Melting Point: 260°C (dec.)
• Boiling Point: °Cat760mmHg
• Flash Point: °C
• Appearance: /
• Density: 1.421g/cm³
• Refractive Index: 1.605
• PKA: -1.17±0.50(Predicted)
• BRN: 2094129
• CAS DataBase Reference: N-METHYLANILINE-P-SULFONIC ACID(CAS DataBase Reference)
• NIST Chemistry Reference: N-METHYLANILINE-P-SULFONIC ACID(24447-99-2)
• EPA Substance Registry System: N-METHYLANILINE-P-SULFONIC ACID(24447-99-2)

Safety Data

• Statements: 36/37/38
• Safety Statements: 26-36
• Hazardous Substances Data: 24447-99-2(Hazardous Substances Data)

Usage

Uses

N-Methylsulphanilic Acid is used in preparation of whole-plastic bicycle frame.

InChI:InChI=1/C7H9NO3S/c1-8-6-2-4-7(5-3-6)12(9,10)11/h2-5,8H,1H3,(H,9,10,11)

Upstream product

• 39169-92-1 4-(N-acetyl-N-methylamino)benzenesulfonyl chloride 
• 857954-06-4 N-methyl-N-(toluene-4-sulfonyl)-sulfanilic acid 
• 515-74-2 sodium sulfanilate 
• 100-61-8 N-methylaniline 
• 70916-29-9 N-methylorthanilic acid 
• 29688-78-6 N-methylanilinium sulfate 
• 29688-78-6 N-methyl-N-phenylammonium sulfate 
• 10034-85-2 hydrogen iodide 
• 50-00-0 formaldehyd 
• 623-11-0 1-methyl-4-nitrosobenzene 
• 579-10-2 N-acetyl-N-methylaniline 

Downstream Products

• 70916-29-9 N-methylorthanilic acid 
• 71794-43-9 3-(methylamino)benzenesulfonic acid 
• 100-61-8 N-methylaniline 

Relevant articles and documents

ISOMERIC TRANSFORMATIONS OF AMINOSULFONIC ACIDS OF THE BENZENE SERIES IN MIXTURES OF SULFURIC AND ACETIC ACIDS

The isomerization rate of aminosulfonic acids in anhydrous binary mixtures of sulfuric and acetic acids is lower than in aqueous sulfuric acid solutions but higher than in 100percent sulfuric acid.This is explained by the differences in the structure and activity of the proton carriers during desulfonation.The rate of transformation of the labile isomers into the meta isomers increases with increase in the acidity of the medium, and this is due to the increase in the resulfonation rate of the protonating molecules of the amines formed during the desulfonation of the aminosulfonic acids.The effect of mercuric sulfate on the isomeric transformations of aminosulfonic acids is explained by the mercuration of the protonated molecules of the amines, which takes place at higher rates than their sulfonation and leads to the formation of the meta-mercury derivatives of the amines.The latter are than converted into the m-aminosulfonic acids by the action of concentrated sulfuric acid.

KINETICS OF SULFONATION OF AMINES OF THE BENZENE SERIES WITH SULFUR TRIOXIDE

The sulfonation of amines of the benzene series with sulfur trioxide in dichloroethane is described by a third-order kinetic equation for an irreversible process, and first order is observed with respect to the compound being sulfonated and second with respect to the sulfur trioxide.The unprotonated molecules of the amines undergo sulfonation, and this leads to the production of the para-aminosulfonic acids with small amounts of the ortho isomers.The reaction mechanism involves electrophilic reaction of the unprotonated amine molecule with the sulfur trioxide dimer S2O6 and subsequent dissociation of the obtained pyrosulfonate with the production of the amino sulfonic acid and sulfur trioxide.

KINETICS OF THE SULFONATION OF AMINES OF THE BENZENE SERIES BY CHLOROSULFONIC ACID

The kinetics of the sulfonation of amines of the benzene series by an equimolar amount of chlorosulfonic acid in o-dichlorobenzene were studied.It was shown that the sulfonation of aniline and N-alkylanilines is described by a second-order kinetic equation for irreversible reactions.The sulfonation of N,N-dialkylanilines by chlorosulfonic acid is described by a first-order kinetic equation for irreversible reactions.The observed relationships are explained by different mechanism for the sulfonation of amines of the benzene series by chlorosulfonic acid.The sulfonation of aniline and N-alkalynilines takes place by direct reaction between the unprotonated molecules of the amines and the HSO3(1+) ion, whereas in the reaction of chlorosulfonic acid with N,N-dialkylanilines complexes of the N,N-dialkylanilines with sulfur trioxide (dialkylanilinesulfotrioxides) are formed initially and then rearrange to the corresponding para-aminosulfonic acids.

REARRANGEMENT OF PHENYL- AND N-ALKYLPHENYLAMMONIUM HYDROGEN SULFATES IN ORGANIC SOLVENTS

The kinetics of the rearrangement of phenyl- and N-alkylphenylammonium hydrogen sulfates in halogen-containing organic solvents were investigated in closed systems and with the removal of the water produced in the reaction.The isomeric composition of the obtained aminobenzenesulfonic acids was also studied.The rearrangement is described by a second-order kinetic equation.The reaction mechanism involves thermal dissociation of the phenyl- and N-alkylphenylammonium hydrogen sulfates at high temperatures to amines (bases) and sulfuric acid, followed by direct sulfonation of the amines (bases) by the sulfuric acid with the formation mostly of para-aminosulfonic acids of the benzene series.

KINETIC OF THE SULFONATION OF AMINES OF THE BENZENE SERIES WITH SULFURIC ACID

The kinetics of the sulfonation of primary, secondary, and tertiary amines of the benzene series with 80-99.7percent sulfuric acid were investigated.It was shown that the unprotonated and protonated forms of the amines, which are present in equilibrium, undergo sulfonation.The effective reaction rate constants and the activation energies for the sulfonation of the unprotonated and protonated molecules of the amines were calculated.The reaction mechanism and the structure of the transition state are discussed.

MECHANISM OF THE SULFONATION OF AROMATIC AMINES BY SULFURIC ACID AT HIGH TEMPERATURES

The kinetics of the rearrangement of unsubstituted and N-substituted phenylammonium hydrogen sulfates to the corresponding aminosulfonic acids of the benzene series were studied.The isomeric composition of the reaction products formed during the sulfonation of amines of the benzene series by various amounts of 100percent H2SO4 was also studied.The rearrangement is described by a second-order kinetic equation.Its effective rate constant at various temperatures and the activation energies were calculated.It is suggested that the sulfonation of aromatic amines by an equimolar amount of sulfuric acid at high temperatures takes place through the dissociation of the arylammonium hydrogen sulfates with the formation of arylamines and sulfuric acid and subsequent direct sulfonation of the arylamines by the sulfuric acid.

KINETICS OF THE SULFONATION OF AMINES OF THE BENZENE SERIES BY OLEUM IN THE PRESENCE OF MERCURIC SULFATE

Sulfonated mixtures with increased contents of the meta isomers are formed during the sulfonation of amine sulfates of the benzene series with oleum containing mercuric sulfate.The following mechanism is proposed for the sulfonation of the amines by oleum in the presence of mercuric sulfate.Two fast reactions take place initially, i.e., sulfonation of the unprotonated molecules of the amines of the benzene series and electrophilic mercuration of the protonated molecules of the amines with the formation of the meta-mercurio derivatives.Electrophilic substitution of the mercury by the sulfo group with formation of the meta-mercuric derivatives then occurs under the influence of the oleum.