|Molar mass||178.23 g·mol−1|
|Melting point||101 °C (214 °F; 374 K)|
|Boiling point||332 °C (630 °F; 605 K)|
|Flash point||171 °C (340 °F; 444 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is: / ?)(|
Phenanthrene is a polycyclic aromatic hydrocarbon composed of three fused benzene rings. The name phenanthrene is a composite of phenyl and anthracene. In its pure form, it is found in cigarette smoke and is a known irritant, photosensitizing skin to light. Phenanthrene appears as a white powder having blue fluorescence.
The compound with a phenanthrene skeleton and nitrogens at the 4 and 5 positions is known as phenanthroline.
The Bardhan–Sengupta phenanthrene synthesis is a classic way to make phenanthrenes.
This process involves electrophilic aromatic substitution using a tethered cyclohexanol group using diphosphorus pentoxide, which closes the central ring onto an existing aromatic ring. Dehydrogenation using selenium makes converts the other rings into aromatic ones as well. The aromatization of six-membered rings by selenium is not clearly understood, but it does produce H2Se.
Phenanthrene can also be obtained photochemically from certain diarylethenes.
Reactions of phenanthrene typically occur at the 9 and 10 positions, including:
- Organic oxidation to phenanthrenequinone with chromic acid
- Organic reduction to 9,10-dihydrophenanthrene with hydrogen gas and raney nickel
- Electrophilic halogenation to 9-bromophenanthrene with bromine
- Aromatic sulfonation to 2 and 3-phenanthrenesulfonic acids with sulfuric acid
- Ozonolysis to diphenylaldehyde
Phenanthrene is more stable than its linear isomer anthracene. A classic and well established explanation is based on Clar's rule. A novel theory invokes so-called stabilizing hydrogen-hydrogen bonds between the C4 and C5 hydrogen atoms.
In February 2014, NASA announced a greatly upgraded database for tracking polycyclic aromatic hydrocarbons (PAHs), including phenanthrene, in the universe. According to scientists, more than 20% of the carbon in the universe may be associated with PAHs, possible starting materials for the formation of life. PAHs seem to have begun forming a couple of billion years after the Big Bang, are widespread throughout the universe, and are associated with new stars and exoplanets.
- Record of CAS RN 85-01-8 in the GESTIS Substance Database of the IFA
- Peter Atkins, J. D. P., Atkins' Physical Chemistry. Oxford: 2010. Pg.443
- "Bardhan Sengupta Synthesis". Comprehensive Organic Name Reactions and Reagents 49. 2010. pp. 215–219. doi:10.1002/9780470638859.conrr049.
- Organic Syntheses, Coll. Vol. 4, p.757 (1963); Vol. 34, p.76 (1954) Link
- Organic Syntheses, Coll. Vol. 4, p.313 (1963); Vol. 34, p.31 (1954) Link.
- Organic Syntheses, Coll. Vol. 3, p.134 (1955); Vol. 28, p.19 (1948) Link.
- Organic Syntheses, Coll. Vol. 2, p.482 (1943); Vol. 16, p.63 (1936) Link.
- Organic Syntheses, Coll. Vol. 5, p.489 (1973); Vol. 41, p.41 (1961) Link.
- Ravatite Mineral Data
- Hoover, Rachel (February 21, 2014). "Need to Track Organic Nano-Particles Across the Universe? NASA's Got an App for That". NASA. Retrieved February 22, 2014.
- Phenanthrene at scorecard.org