Anthracene

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Anthracene
Names
IUPAC name
Anthracene
Other names
Freitalite
Paranaphthalene
Properties
C14H10
Molar mass 178.234 g/mol
Appearance Colorless crystalline solid
Odor Aromatic
Density 1.28 g/cm3 (25 °C)
Melting point 216 °C (421 °F; 489 K)
Boiling point 341.3 °C (646.3 °F; 614.5 K)
0.022 mg/L (0 °C)
0.044 mg/L (25 °C)
0.29 mg/L (50 °C)
Solubility Slightly soluble in acetone, benzene, carbon disulfide, chloroform, diethyl ether, ethanol, toluene, xylene
Solubility in carbon tetrachloride 0.732 g/100 g
Solubility in ethanol 0.076 g/100 g (16 °C)
0.19 g/100 g (19.5 °C)
0.328 g/100 g (25 °C)
Solubility in hexane 0.37 g/100 g
Solubility in methanol 0.18 g/100 g (19.5 °C)
Solubility in toluene 0.92 g/100 g (16.5 °C)
12.94 g/100 g (100 °C)
Vapor pressure 6.56·10-6 mmHg at 25 °C
Thermochemistry
207.5 J·mol-1·K-1
129.2 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich
Flash point 121 °C (250 °F; 394 K)
Lethal dose or concentration (LD, LC):
100-149 mg/kg (rat, oral)
Related compounds
Related compounds
Benzene
Naphthalene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Anthracene is an organic chemical compound, a solid polycyclic aromatic hydrocarbon (PAH) with the chemical formula C14H10, consisting of three fused benzene rings.

Properties

Chemical

Under UV light, anthracene displays fluorescence, emitting blue light. Its crystals are known to be triboluminescent.

Anthracene photodimerizes by the action of UV light, forming dianthracene. It reverts to anthracene under heat treatment or with UV irradiation below 300 nm.

Anthracene can be oxidized by hydrogen peroxide or vanadyl acetylacetonate to anthraquinone.[1]

Electrophilic substitution of anthracene occurs at the 9 position. For example, formylation affords 9-anthracenecarboxaldehyde. Substitution at other positions is effected indirectly, for example starting with anthroquinone. Bromination of anthracene gives 9,10-dibromoanthracene.

Physical

Anthracene is a colorless solid, insoluble in water but more soluble in organic solvents. While similar to naphthalene, anthracene's odor is much weaker and thus is much more tolerable, and will not fill up a room.

Anthracene sublimes when heated at 226.5 °C, at a low pressure of 53 mmHg.

Availability

Anthracene can be bought from chemical suppliers.

Anthracene can be extracted from coal tar, which contains around 1.5% anthracene. While low, this source is the cheapest.

Anthracene can be found in nature as the rare mineral freitalite, usually in coal deposits.

Preparation

In laboratory, anthracene can be prepared by cyclodehydration of o-methyl- or o-methylene-substituted diarylketones in the so-called Elbs reaction, for example from o-tolyl phenyl ketone. This route is expensive and extraction from coal tar is thus much cheaper.

Projects

  • Fluorescent compound and UV tracer
  • Compound collecting
  • Make anthraquinone
  • Make alizarin
  • Wide band-gap organic semiconductor

Handling

Safety

Unlike its lighter cousin, naphthalene, anthracene has much lower toxicity and does not appear, based on current data, to be carcinogenic.

Storage

In closed airtight bottles, away from sunlight.

Disposal

Should be neutralized by controlled incineration, in a special burner. Alternatively, oxidizing solutions, which can safely break down aromatics, may be used. Strong UV light will also break down this compound.

References

  1. Charleton, Kimberly D. M.; Prokopchuk, Ernest M. (2011). "Coordination Complexes as Catalysts: The Oxidation of Anthracene by Hydrogen Peroxide in the Presence of VO(acac)2". Journal of Chemical Education. 88 (8): 1155–1157

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