Title: p-Toluenesulfonic Acid
CAS Registry Number: 104-15-4
CAS Name: 4-Methylbenzenesulfonic acid
Synonyms: tosic acid
Molecular Formula: C7H8O3S
Molecular Weight: 172.20
Percent Composition: C 48.82%, H 4.68%, O 27.87%, S 18.62%
Line Formula: CH3C6H4SO3H
Literature References: Prepd by sulfonation of toluene with 96-100% H2SO4; when carried out at 75° the compn of the reaction product is 75%
para-, 19%
ortho- and 6%
meta-toluenesulfonic acid. Convenient lab prepn: L. F. Fieser,
Experiments in Organic Chemistry (Boston, 3rd ed., 1955) p 144. The separation of toluene from petroleum fractions can be accomplished by sulfonation with H2SO4 at 60°.
Properties: Monoclinic leaflets or prisms. Also reported as crystallizing with 1H2O or 4H2O. When anhydrous, mp 106-107°. Metastable form, mp 38°. bp20 140°. bp0.1 185-187°. Freely sol in water, about 67 g/100 ml. Sol in alc and ether.
Melting point: mp 106-107°; mp 38°
Boiling point: bp20 140°; bp0.1 185-187°
Derivative Type: Sodium salt
Molecular Formula: C7H7NaO3S
Molecular Weight: 194.18
Percent Composition: C 43.30%, H 3.63%, Na 11.84%, O 24.72%, S 16.51%
Properties: Orthorhombic plates, very sol in water.
CAUTION: Highly irritating to skin, mucous membranes.
Use: In dye chemistry; in manuf of oral antidiabetic drugs.