8157. β-Resorcylic Acid

Nomenclature

CAS number: 89-86-1
2,4-Dihydroxybenzoic acid; 2,4-dihydroxybenzenecarboxylic acid; BRA.
C7H6O4; mol wt 154.12.
C 54.55%, H 3.92%, O 41.52%.

Description and references

Prepared from resorcinol and KHCO3 in glycerol or water by heating and passing CO2 through the mixture: Brunner, Ann. 351, 320 (1907). Cf. Bistrycki, Kostanecki, Ber. 18, 1984 (1885); Nierenstein, Clibbens, Org. Synth. coll. vol. II, 557 (1943).

Chemical structure

Properties

Hydrated crystals from water. Becomes anhydr at 100°, mp 213° (rapid heating). pK (25°) 3.30. Sol in hot water, alcohol, ether, olive oil. Boiling with water, acids or salt solns results in loss of CO2.

Use

Intermediate for dyestuffs and drugs; spot test reagent for iron.