683. Anthragallol

Nomenclature

CAS number: 602-64-2
1,2,3-Trihydroxy-9,10-anthracenedione; 1,2,3-trihydroxyanthraquinone; anthragallic acid; anthracene brown.
C14H8O5; mol wt 256.21.
C 65.63%, H 3.15%, O 31.22%.

Description and references

From gallic acid and benzoic acid with sulfuric acid at 125° or from phthalic anhydride and pyrogallol with sulfuric acid at 160°: Seuberlich, Ber. 10, 39 (1877). Other methods: Kubota, Perkin, J. Chem. Soc. 127, 1889 (1925); Perkin, Story, ibid. 1929, 1399; Cross, Perkin, ibid. 1930, 292. Absorption spectrum: Meyer, Fischer, Ber. 46, 85 (1913).

Chemical structure

Properties

Brown crystals, mp 312-313°. Sublimes 290°. Slightly sol in water, chloroform; sol in alcohol, ether, glacial acetic acid. Its soln in concd H2SO4 is reddish-brown. Greenish-brown soln in ammonia water changes to blue on heating. Forms salts with Na, K, Ba, Tl, Pb, La, Ce, Nd, Co.

Derivative

Trimethyl ether.
C17H14O5; mol wt 298.29.
C 68.45%, H 4.73%, O 26.82%.

Properties

Yellow needles from benzene + petr ether, mp 168°. Insol in water solns of alkalies.