Anthraquinone

Anthraquinone (9,10-dioxoanthracene) is an anthracene. It has the appearance of yellow or light gray to gray-green solid crystalline powder.

Its other names are 9,10-anthracenedione, anthradione, 9,10-anthrachinon, anthracene-9,10-quinone, 9,10-dihydro-9,10-dioxoanthracene, and trade names Hoelite, Morkit, Corbit, and others.

Physical properties

It is aniline. It is chemically fairly stable under normal conditions.

Natural occurrences

Anthraquinones naturally occur in some plants (eg. lichens, and insects, where they serve as a basic skeleton for their pigments. Natural anthraquinone derivatives tend to have laxative effects.

Chemistry

There are several ways to obtain anthraquinone:

• Oxidation of anthracene
• Condensation of Friedel-Crafts substitution). The resulting o-benzoylbenzoic acid then undergoes cyclization, forming anthraquinone.
• naphthoquinone and a 1,3-diene followed by oxidation)
• Retro-DA reaction: the Rickert-Alder reaction.

In a classic ketone group into a methylene group) after which the glycerol is added.

Industrial applications

Anthraquinone is used in production of pigments are derivatives of anthraquinone. Anthraquinone is also used as a catalyst in production of wood pulp in pulp and paper industry. Another use is as a bird repellant on seeds.

A derivative of anthraquinone (2-ethylanthraquinone) is used to produce hydrogen peroxide commercially.

Medical uses

Anthraquinone is used as a laxative. Prolonged use and abuse leads to melanosis coli.^[2][3]

References