Phenalene

For the di-substituted benzene ring molecular fragment, see phenylene.

Phenalene

Names
Preferred IUPAC name 1H-Phenalene
Other names 1-Benzonaphthene; 1H-Benzonaphthene; Perinaphthene; Perinaphthindene; peri-Naphthindene
Identifiers
CAS Number	203-80-5  N
3D model (JSmol)	Interactive image
ChEBI	CHEBI:33082  Y
ChemSpider	8795  Y
ECHA InfoCard	100.005.371
PubChem CID	9149
UNII	DQ27KZF2V7  Y
CompTox Dashboard (EPA)	DTXSID5075369
InChI InChI=1S/C13H10/c1-4-10-6-2-8-12-9-3-7-11(5-1)13(10)12/h1-8H,9H2 Y Key: XDJOIMJURHQYDW-UHFFFAOYSA-N Y InChI=1/C13H10/c1-4-10-6-2-8-12-9-3-7-11(5-1)13(10)12/h1-8H,9H2 Key: XDJOIMJURHQYDW-UHFFFAOYAK
SMILES c3c1cccc2\C=C/Cc(c12)cc3
Properties
Chemical formula	C13H10
Molar mass	166.22 g/mol
Appearance	white solid
Density	1.139 g/cm3
Melting point	159–160 °C (318–320 °F; 432–433 K)
Acidity (pKa)	18.1 (in DMSO) [1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N  verify  (what is  YN ?) Infobox references

1H-Phenalene, often called simply phenalene is a polycyclic aromatic hydrocarbon (PAH). Like many PAHs, it is an atmospheric pollutant formed during the combustion of fossil fuels. ^[2] It is the parent compound for the phosphorus-containing phosphaphenalenes.

The name was proposed by German chemists in 1922 as a contraction of periphenonaphthalene. ^[3]

It has been discovered in interstellar space in the Taurus Molecular cloud (TMC-1) as part of the QUIJOTE survey. ^[4]

Reactions

Phenalene is deprotonated by potassium methoxide to give the phenalenyl anion. ^[5]

See also

• Zethrene
• Cyclopentadiene

References

1. Bausch, M. J.; Guadalupe-fasano, C.; Jirka, G.; Peterson, B.; Selmarten, D. (1991-01-01). "Examinations of Dimethyl Sulfoxide-Phase Equilibrium Acidities of Selected Polycyclic Aromatic Compounds". Polycyclic Aromatic Compounds. 2 (1): 19–27. doi:10.1080/10406639108047854. ISSN   1040-6638.
2. Gao H, Ma MQ, Zhou L, Jia RP, Chen XG, Hu ZD (2007). "Interaction of DNA with aromatic hydrocarbons fraction in atmospheric particulates of Xigu District of Lanzhou, China". J Environ Sci (China). 19 (8): 948–54. Bibcode:2007JEnvS..19..948G. doi:10.1016/S1001-0742(07)60156-9. PMID   17966851.
3. Fritz Mayer and Adolf Sieglitz (1922). "Investigations and Ring Closures in the Series of the Methylnaphthalenes". Journal of the Chemical Society. 122 (1–2).
4. Cabezas, C.; Agúndez, M.; Pérez, C.; Villar-Castro, D.; Molpeceres, G.; Pérez, D.; Steber, A. L.; Fuentetaja, R.; Tercero, B.; Marcelino, N.; Lesarri, A.; Vicente, P. de; Cernicharo, J. (2025-09-01). "Discovery of interstellar phenalene (c-C13H10): A new piece in the chemical puzzle of PAHs in space". Astronomy & Astrophysics. 701: L8. doi:10.1051/0004-6361/202556687. ISSN   0004-6361.
5. Reid, D. H. (1965-01-01). "The chemistry of the phenalenes". Quarterly Reviews, Chemical Society. 19 (3): 274. doi:10.1039/qr9651900274. ISSN   0009-2681.