5187. Isonicotinic Acid

Nomenclature

CAS number: 55-22-1
4-Pyridinecarboxylic acid; γ-pyridinecarboxylic acid; γ-picolinic acid.
C6H5NO2; mol wt 123.11.
C 58.54%, H 4.09%, N 11.38%, O 25.99%.

Description and references

Prepd by permanganate oxidation of γ-picoline: Gilman, Broadbent, J. Am. Chem. Soc. 70, 2757 (1948); Fields, US 2946801 (1960 to Standard Oil); from 4-ethylpyridine: Wibaut, Arens, Rec. Trav. Chim. 60, 137 (1941); from citric acid to citrazinic acid to 2,6-dichloroisonicotinic acid: Behrmann, Hofmann, Ber. 17, 2681 (1884); Wibaut, Rec. Trav. Chim. 63, 141 (1944). Prepn of ethyl ester: Burrus, Powell, J. Am. Chem. Soc. 67, 1469 (1945).

Chemical structure

Properties

Platelets, mp 319°. Sublimes at 260° and 15 mm pressure. pK (25°) 4.96. pH of satd aq soln 3.6. Sparingly sol in cold water (0.52 g/100 ml at 20°), more sol in hot water. Practically insol in benzene, ether, boiling alcohol.

Derivative

Methyl ester.
C7H7NO2; mol wt 137.14.
C 61.31%, H 5.14%, N 10.21%, O 23.33%.

Properties

Liq, slight odor, similar to mint or oil of wintergreen. mp 8.5°. bp21 104°; bp760 209° (slight decompn).

Derivative

Ethyl ester.

Properties

Liq, ester-like odor. Needles, when cooled by salt-ice mixture, mp 23°. d415 1.0091 (liq). bp5 78.5°; bp15 110°; bp760 220°. Sol in alcohol, ether, chloroform, benzene. Practically insol in water.