9533. p-Toluenesulfonic Acid

Nomenclature

CAS number: 104-15-4
4-Methylbenzenesulfonic acid; tosic acid.
C7H8O3S; mol wt 172.20.
C 48.82%, H 4.68%, O 27.87%, S 18.62%.

Description and references

Prepd by sulfonation of toluene with H2SO4. 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°.

Chemical structure

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.

Derivative

Sodium salt.

Nomenclature

CAS number: 6263-41-8
C7H7NaO3S; mol wt 194.18.
C 43.30%, H 3.63%, Na 11.84%, O 24.72%, S 16.51%.

Properties

Orthorhombic plates, very sol in water.

Derivative

Monohydrate.

Nomenclature

CAS number: 6192-52-5
C7H8O3S.H2O; mol wt 190.22.
C 44.20%, H 5.30%, O 33.64%, S 16.86%.

Properties

Freely sol in water.

Caution

Highly irritating to skin, mucous membranes.

Use

In dye chemistry; in manuf of oral antidiabetic drugs. Derivatizing agent.