What Is Anthracene?
Anthracene is a polycyclic aromatic hydrocarbon consisting of three fused benzene rings. It has a molecular formula of C14H10 and a molecular weight of 178.23. At room temperature, anthracene is a white solid that emits violet fluorescence at 400-500 nm. It is insoluble in water and ethanol but soluble in hot toluene.
Uses of Anthracene
Anthracene is used in the production of various synthetic dyes, including anthraquinone dyes like alizarin and indanthrene. It is also a precursor for anthraquinone, an important dye intermediate, and is used in producing carbon black and tanning agents. Additionally, anthracene is used in paints, insect repellents, wood preservatives, herbicides, plant growth regulators, and fluorescent dyes.
Principles of Anthracene
1. Anthracene Production Methods
Anthracene is typically produced industrially by separating and purifying it from the anthracene oil fraction of coal tar. In the laboratory, it can be synthesized through the reduction of anthraquinone, or by condensation reactions using benzyl chloride and aluminum chloride, or tetrabromobenzene with benzene.
2. Chemical Reactions of Anthracene
Anthracene is photoreactive, undergoing a [4+4] cyclization reaction upon exposure to ultraviolet light, producing a dimer that reverts to the monomer upon heating or UV irradiation. The central ring of anthracene is highly reactive, undergoing aromatic electrophilic substitution mainly at positions 9 and 10, oxidation to anthraquinone, and reduction to 9,10-dihydroanthracene. It also undergoes a Diels-Alder reaction with singlet oxygen.
Types of Anthracene
Anthracene is available as a chemical reagent in various purities and is sold in quantities suitable for both laboratory and industrial applications. Additionally, deuterated derivatives like anthracene d-10 are used as internal standards for GC-MS analysis.
Other Information on Anthracene
Safety of Anthracene
Anthracene is irritating to the skin and can decompose under heat or strong oxidants, producing irritating and toxic fumes. Proper safety precautions should be taken when handling this compound.