8050. Quinalizarin

Nomenclature

CAS number: 81-61-8
1,2,5,8-Tetrahydroxy-9,10-anthracenedione; 1,2,5,8-tetrahydroxyanthraquinone; alizarin bordeaux B; C.I. Mordant Violet 26; C.I. 58500.
C14H8O6; mol wt 272.21.
C 61.77%, H 2.96%, O 35.27%.

Description and references

From hemipic (hemipinic) acid and hydroquinone with H2SO4: Liebermann, Kostanecki, Ann. 240, 245 (1887); Liebermann, Wense, Ber. 20, 862 (1887). From alizarin or quinizarin by treatment with 80% oleum, then boiling with caustic: Gattermann, J. Prakt. Chem. [2] 43, 246 (1891); Schmidt, ibid. 237, 242 (1891); Bull. Soc. Ind. Mulhouse 84, 409 (1914). See also: Colour Index vol. 4 (3rd ed., 1971) p 4519.

Chemical structure

Properties

Red needles with green metallic luster from acetic acid or from nitrobenzene or by sublimation in vacuo. mp >275°. Absorption spectrum: Meek, Watson, J. Chem. Soc. 109, 544 (1916); Meek, ibid. 111, 969 (1917). Insol in water. Very slightly sol in most other solvents. Dissolves in aq solns of alkalies with reddish-violet, in acetic acid with yellow, in sulfuric acid with blue-violet color.

Use

Dyes cotton mordanted with Al salts dark red, cotton mordanted with Cr salts bluish-violet. No longer used as a dye, except occasionally in printing cotton.