Chemical Properties
orange to red-brown crystalline powder
Definition
ChEBI: A dihydroxyanthraquinone having the two hydroxy substituents at the 1- and 4-positions; formally derived from anthraquinone by replacement of two hydrogen atoms by hydroxy groups
Preparation
commonly known as Quinizarin. (a) Boric acid, boric acid and mercury, boric acid and nitrous acid or nitrous acid and mercury in the presence of Anthracene-9,10-dione with sulfuric acid; (b) In the presence of boric acid and nitrous acid, treated with sulfuric acid ?1-Hydroxyanthracene-9,10-dione or 2-Hydroxyanthracene-9,10-dione, (c)In the presence of boric acid, treated with sulfuric acid 1-Hydroxy-4-nitroanthracene-9,10-dione?or?1,4-Dichloroanthracene-9,10-dione?; (d) in the Boric acid and where did in the presence of sulfuric acid, Phthalic anhydride and 4-Chlorophenol?or Hydroquinone condensation, closed loop.
General Description
1,4-Dihydroxyanthraquinone is an organic dye molecule with an aromatic structure. It is a derivative of anthraquinone bearing hydroxyl moieties. They may find uses in pharmacological, biochemical and dye industries. Anthraquinone dye are resistant to degradation.
Flammability and Explosibility
Nonflammable
Properties and Applications
orange. Orange red powder. Insoluble in water, soluble in ether, in strong base in certain solubility, but soluble in organic solvent oil, etc. In concentrated sulfuric acid in green yellow fluorescence. Mainly used for oil coloring. Also used in all kinds of plastic and resin, light industry products coloring.
Purification Methods
Crystallise quinizarin from glacial acetic acid. [Beilstein 8 H 450, 8 IV 3260.]
