Nomenclature
CAS number: 82-12-2
1,2,3,5,6,7-Hexahydroxy-9,10-anthracenedione; 1,2,3,5,6,7-hexahydroxyanthraquinone; rufigallic acid; C.I. 58600.
C
14H
8O
8; mol wt 304.21.
C 55.27%, H 2.65%, O 42.07%.
Description and references
Prepd by the action of H2SO4 on gallic acid: Robiquet, Ann. 19, 204 (1836); by dry distn of gallic acid: Kunz-Krause,
Manicke, Ber. 53, 190
(1920). See also: Colour Index vol. 4 (3rd ed., 1971) p 4520.
Properties
Red needles. Does not melt, but sublimes with
partial decompn upon heating. Absorption spectrum: Treibs, Steinmetz, Ann. 506, 171, 191 (1933). Practically
insol in water. Freely sol in acetone; slightly sol in alcohol, ether,
with yellow color. Sol in alkali hydroxide solns with violet color,
but is soon dec by oxidation.Derivative
Hexamethyl ether.
C
20H
20O
8; mol wt 388.37.
C 61.85%, H 5.19%, O 32.96%.
Properties
Yellow needles, mp 240°.Use
For color reactions with Zr and Hf.