8-Hydroxyquinoline

History

8-hydroxyquinoline was first obtained by Hugo Weidel and his student Albert Cobenzl in 1880. They decarboxylated so-called oxycinchoninic acid (from cinchonine) and characterized the resulting compound as melting at about 70°C. They identified that the hydroxy group is on the benzene ring (but not its particular place) and called the compound oxyquinoline and α-quinophenol.

In the following year more chemists found other ways to make the compound. Zdenko Hans Skraup discovered a way to synthesize substituted quinolines from substituted phenols and described three isomers of oxyquinoline, identifying the structure of 8-hydroxyquinoline. and his student Karl Bedall made the compound from a sulphonic acid independently at about the same time, but misidentified its structure.

By 1888 azo dyes were made from the compound.

In the 1920s insoluble chelates of 8-hydroxyquinoline were discovered.

Bioactivity

The complexes as well as the heterocycle itself exhibit antiseptic, disinfectant, and pesticide properties, functioning as a transcription inhibitor.{{cite web |title=8-Hydroxyquinoline |url=http://www.sigmaaldrich.com/US/en/product/sial/h6878 |access-date=2022-02-15 |publisher=Sigma-Aldrich}} Its solution in alcohol is used in liquid bandages. It once was of interest as an anti-cancer drug.

A thiol analogue, 8-mercaptoquinoline is also known.

The roots of the invasive plant Centaurea diffusa release 8-hydroxyquinoline, which has a negative effect on plants that have not co-evolved with it.

References

References

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2. (2002). "The structure of the blue luminescent δ-phase of tris(8-hydroxyquinoline)aluminium(III) (Alq₃)". Chemical Communications.
3. (2006). "Configuration-Specific Synthesis of the Facial and Meridional Isomers of Tris(8-hydroxyquinolinate)aluminum (Alq₃)". Inorganic Chemistry.
4. (2006). "Effective Manipulation of the Electronic Effects and Its Influence on the Emission of 5-Substituted Tris(8-quinolinolate) Aluminum(III) Complexes". Chemistry: A European Journal.
5. (1997). "Excited-State Processes in 8-Hydroxyquinoline: Photoinduced Tautomerization and Solvation Effects". The Journal of Physical Chemistry B.
6. (1880). "Über Derivate der Cinchoninsäure und des Chinolins". Monatshefte für Chemie und verwandte Teile anderer Wissenschaften.
7. "Verfahren zur Darstellung der Oxychinoline durch Behandlung von Mononitro- und Monamido-Phenolen mit Glycerin und Schwefelsäure".
8. (1881). "Ueber Oxychinolin aus Chinolinsulfosäure". Berichte der Deutschen Chemischen Gesellschaft.
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10. (1888). "Journal of the Society of Dyers and Colourists". Society of Dyers and Colourists.
11. Berg, R.. (1927). "Neue Wege zur Bestimmung und Trennung der Metalle mit Hilfe von o-Oxychinolin". Zeitschrift für analytische Chemie.
12. Phillips, J. P.. (1956). "The Reactions of 8-Quinolinol". Chemical Reviews.
13. "8-Hydroxyquinoline". Medical Dictionary Online.
14. (1999). "Synthesis and Cytotoxicity Evaluation of some 8-Hydroxyquinoline Derivatives". Journal of Pharmacy and Pharmacology.
15. (2005). "Structural Chemistry of Complexes of (n-1)d¹⁰ns Metal Ions with β-N-Donor Substituted Thiolate Ligands (m=0, 2)". Coordination Chemistry Reviews.
16. (2004). "Biogeographical variation in community response to root allelochemistry: novel weapons and exotic invasion". Ecology Letters.