5155. Isobutyric Acid

Nomenclature

CAS number: 79-31-2
2-Methylpropanoic acid; dimethylacetic acid; isobutanoic acid; isopropylformic acid.
C4H8O2; mol wt 88.11.
C 54.53%, H 9.15%, O 36.32%.

Description and references

Prepn from 1-nitroisobutane: Lippincott, Hass, Ind. Eng. Chem. 31, 118 (1939); from methallyl chloride: Towle, Hall, US 2667508 (1954 to Standard Oil Co. of Indiana); from propylene: Alderson, US 3020314 (1962 to du Pont); from 2-methylpropane + CO with HF catalyst: Friedman, Cotton, J. Org. Chem. 27, 481 (1962).

Chemical structure

Properties

Liquid; pungent odor like that of butyric acid, but not as unpleasant. bp760 152-155°. mp 47°. d420 0.950. nD20 1.3930. Flash pt, open cup: 170°F (77°C). Flammable, corrosive. Sol in 6 parts of water; misc with alcohol, chloroform, ether.

Caution

Mild irritant.