Methyl p-toluenesulfonate Property

Melting point:

25-28 °C(lit.)

Boiling point:

144-145 °C5 mm Hg(lit.)

Density 

1.234 g/mL at 25 °C(lit.)

vapor density 

6.45 (vs air)

vapor pressure 

1 mm Hg ( 20 °C)

refractive index 

n20/D 1.5172(lit.)

Flash point:

>230 °F

storage temp. 

2-8°C

solubility 

Chloroform (Slightly), Methanol (Slightly)

form 

Liquid or Low Melting Solid

color 

White to yellow

Water Solubility 

Insoluble

Sensitive 

Moisture Sensitive

BRN 

609209

LogP

1.88 at 25℃

CAS DataBase Reference

80-48-8(CAS DataBase Reference)

NIST Chemistry Reference

Benzenesulfonic acid, 4-methyl-, methyl ester(80-48-8)

EPA Substance Registry System

Benzenesulfonic acid, 4-methyl-, methyl ester (80-48-8)

Safety

Hazard Codes 

C,Xn

Risk Statements 

22-34-43-40-36/37/38

Safety Statements 

26-36/37/39-45-24

RIDADR 

UN 3261 8/PG 2

WGK Germany 

3

RTECS 

XT7000000

F 

21

Autoignition Temperature

896 °F

TSCA 

Yes

HazardClass 

8

PackingGroup 

III

HS Code 

29051900

Hazardous Substances Data

80-48-8(Hazardous Substances Data)

Toxicity

LD50 orally in Rabbit: 341 mg/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H302Harmful if swallowed

H314Causes severe skin burns and eye damage

H317May cause an allergic skin reaction

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P270Do not eat, drink or smoke when using this product.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

Methyl p-toluenesulfonate Chemical Properties,Usage,Production

Chemical Properties

white to slightly yellow low melting solid. Soluble in alcohol, ether, benzene, insoluble in water. Hygroscopic.

Uses

Methyl p-toluenesulfonate is used as a methylating agent in organic synthesis. It acts as a catalyst for alkyd resins. It is also employed in selective 1-substitution reaction of tetrazole. Further, it is used in the preparation of dyes.

Uses

Methyl p-Toluenesulfonate can be used in the manufacture of dyes and organic synthesis, and also is the raw materials of methylation.

Preparation

Methyl p-toluenesulfonate was synthesized by the reaction of p-toluenesulfonyl chloride with methanol. Mix p-toluenesulfonyl chloride and methanol, slowly add 25% sodium hydroxide solution, control the temperature below 25 °C, stop adding alkali when the pH is 9, continue stirring for 2 hours, and leave overnight. The lower layer of reactant was taken, the upper layer was extracted with benzene, the extract was recovered with benzene and then combined with the lower layer, washed with water and 5% potassium carbonate solution in turn, dried and distilled under reduced pressure to obtain the finished product of methyl p-toluenesulfonate.

Synthesis Reference(s)

Chemical and Pharmaceutical Bulletin, 29, p. 623, 1981 DOI: 10.1248/cpb.29.623
Synthetic Communications, 15, p. 1057, 1985 DOI: 10.1080/00397918508076842

General Description

Methyl p-toluenesulfonate is sulfonate ester present as potentially genotoxic impurity in drug substances. Kinetics of reactions of methyl p-toluenesulfonate with N,N-dimethylaniline has been investigated. It participates in selective 1-substitution reaction of tetrazole.

Hazard

Toxic by ingestion and inhalation, strongirritant to skin and eyes.

Safety Profile

Poison by ingestion and subcutaneous routes. An eye and severe skin irritant. A vesicant and skin sensitizer. Questionable carcinogen with experimental tumorigenic data. When heated to decomposition it emits toxic fumes of SOx.

Purification Methods

The ester is purified by distillation in vacuo and could be crystallised from pet ether or Et2O/pet ether at low temperature. It is a powerful methylating agent, is TOXIC andis a skin irritant, so it is better to purify it by repeated distillation. [IR: Schreiber Anal Chem 21 1168 1949, Buehler et al. J Org Chem 2 167 1937, Roos et al. Org Synth Coll Vol I 145 1948, Beilstein 11 IV 247.]