Quinone
Thequinonesare a class oforganic compoundsthat are formally "derived fromaromaticcompounds [such asbenzeneornaphthalene] by conversion of an even number of –CH= groups into –C(=O)– groups with any necessary rearrangement ofdouble bonds",resulting in" a fullyconjugatedcyclicdionestructure ".[1][2][3] The archetypical member of the class is1,4-benzoquinoneor cyclohexadienedione, often called simply "quinone" (thus the name of the class). Other important examples are1,2-benzoquinone(ortho-quinone),1,4-naphthoquinoneand9,10-anthraquinone.
The name is derived from that ofquinic acid(with the suffix "-one" indicating a ketone), since it is one of the compounds obtained upon oxidation of quinic acid.[4]Quinic acid, likequinineis obtained fromcinchona bark,calledquinaquinain the indigenous languages of Peruvian tribes.
Properties
[edit]Quinones are oxidized derivatives of aromatic compounds and are often readily made from reactive aromatic compounds withelectron-donating substituentssuch asphenolsandcatechols,which increase the nucleophilicity of the ring and contributes to the largeredox potentialneeded to break aromaticity. (Quinones are conjugated but not aromatic). Quinones are electrophilicMichael acceptorsstabilised by conjugation. Depending on the quinone and the site of reduction, reduction can either rearomatise the compound or break the conjugation.Conjugate additionnearly always breaks the conjugation.
The termquinoneis also used more generally for a large class of compounds formally derived from aromatic quinones through replacement of somehydrogenatoms by other atoms or radicals.
-
Chloranil,a reagent in organic chemistry -
Lawsone,a dye present in the leaves of the henna plant -
Alizarin,a common red dye -
DDQ,a reagent in organic chemistry -
Daunorubicin,an anticancer drug
Reactions
[edit]Quinones form polymers by formation of hydrogen bonds with ρ-hydroquinone.[5]
Reduction
[edit]Quinones areoxidizing agents,sometimes reversibly so. Relative tobenzoquinone,more strongly oxidizing quinones includechloraniland2,3-dichloro-5,6-dicyano-1,4-benzoquinone(also known as DDQ).[6]
The oxidizing power of quinones is enhanced by the presence of acids.[7]In acidic conditions, quinone undergoes two-electron and two-proton reduction tohydroquinone.
In alkaline conditions, quinones undergo a reversible single-step, two-electron reduction. In neutral conditions, quinones may undergo either a one-proton, two-electron reduction or a two-electron reduction. Inaproticmedia, quinones undergo two-step reduction without protons.[8]In the first step, a short-livedsemiquinoneintermediate is formed. In the second step, the semiquinone is reduced into a quinone dianion.
9,10-Anthraquinone-2,7-disulphonic acid (AQDS) a quinone similar to one found naturally inrhubarbhas been used as a charge carrier in metal-freeflow batteries.[9]
Addition
[edit]Quinones undergo addition reaction to form 1,4-addition products.[10]An example of 1,4-addition reaction is the addition ofhydrogen chlorideto form chlorohydroquinone:
Quinones can undergoDiels–Alder reactions.[10]The quinone acts as the dienophile and reacts with a diene at a carbon-carbon double bond.
InDiels–Alder reactionsquinones are used as dienophiles. Historically importantsynthesesincludecholesterol,cortisone,morphine,andreserpine.[11]
Occurrence and uses
[edit]Production of hydrogen peroxide
[edit]A large scale industrial application of quinones is for the production ofhydrogen peroxide.2-Alkylanthraquinones are hydrogenated to the corresponding hydroquinones (quinizarins), which then transferH
2to oxygen:
- dihydroanthraquinone +O
2→anthraquinone+H
2O
2
in this way, several million metric tons ofH
2O
2are produced annually.[12]
1,4-Naphthoquinone,derived by oxidation of naphthalene withchromium trioxide.[13]It is the precursor to anthraquinone.
Biochemistry
[edit]Numerous quinones are significant roles in biology. Vitamin K, which is involved in coagulation of blood, is a quinone.Ubiquinone-10 is a naturally occurring 1,4-benzoquinone involved inrespirationapparatus.Plastoquinoneis a redox relay involved in photosynthesis.Pyrroloquinoline quinoneis another biological redox cofactor.
Quinones are conjectured to occur in all respiring organisms.[14]Some serve as electron acceptors in electron transport chains such as those inphotosynthesis(plastoquinone,phylloquinone), andaerobic respiration(ubiquinone). Phylloquinone is also known asvitamin K1as it is used by animals to carboxylate certain proteins, which are involved inblood coagulation,boneformation, and other processes. Conversely, the toxicity ofparacetamolis due to its metabolism to aquinone imine,which then reacts with liver proteins to cause liver failure.
The auto-oxidation of the neurotransmitterdopamineand its precursor L-Dopa generates the comparatively stable dopamine quinone which inhibits the functioning of dopamine transporter (DAT) and theTHenzyme and leads to low mitochondrialATPproduction.[15]
The benzoquinoneblattellaquinoneis a sexpheromoneincockroaches.In the spray ofbombardier beetles,hydroquinone reacts with hydrogen peroxide to produce a fiery blast of steam, a deterrent in the animal world.
Medical
[edit]Several quinones are of pharmacological interest. They form a major class of anticancer cytotoxins. One example isdaunorubicin,which is antileukemic.[14]Some of them show anti-tumoralactivity. They embody some claims inherbal medicine.These applications include purgative (sennosides), antimicrobial and antiparasitic (rheinandsaprorthoquinone,atovaquone), anti-tumor (emodinandjuglone), inhibition ofPGE2biosynthesis (arnebinoneandarnebifuranone) and anti-cardiovascular disease(tanshinone).[16]Malbranchea cinnamomeais a thermophilic fungus, which produces a quinone antibiotic.
Another quinone-containing drug isMecarbinate(dimecarbine), made by the reaction of ethylN-methyl-β-aminocrotonatewith para-benzoquinone. Others includeAmendol,Oxyphemedol,Phemedolall in FR5142 (M) ― 1967-06-05.[clarification needed]Note: These are all indoles made via theNenitzescu indole synthesis.The antineoplasticApaziquone.
Benzoquinone compounds are a metabolite ofparacetamol.[17]
Dyes
[edit]Many natural and artificial coloring substances (dyesandpigments) are quinone derivatives, for instancelawsoneis the active dye compound inhenna.They are second only toazo dyesin importance as dyestuffs, with particular emphasis on blue colors.Alizarin(1,2-dihydroxy-9,10-anthraquinone), extracted from themadderplant, was the first natural dye to be synthesized from coal tar.
Photography
[edit]A commercial application of quinones is inblack-and-white photography.Black-and-white film is covered with an emulsion containing silver bromide or silver iodide crystals, which exposure to light activates. Hydroquinone is used to reduce the activated silver ions to metallic silver. During this process, hydroquinone is oxidized to quinone. All silver halide not activated by light or reduced by hydroquinone is removed, leaving a negative by deposited silver where the film had been struck by light.[18]
Nomenclature
[edit]Quinones are commonly named with a prefix that indicates the parent aromatic hydrocarbon ( "benzo-" for benzene, "naphtho-" for naphthalene, "anthra-" foranthracene,etc.) and the "-quinone" suffix. Infix multipliers "-di-", "-tri-", "-tetra-" (etc.) are used when there are 4, 6, 8 (etc.) carbonyls. The position of the carbonyl groups can be indicated before the prefix (as in "1,4,5,8-naphthodiquinone" ) or after it ( "anthra-1,4-quinone" ).
Structural analogues of quinones
[edit]- Quinone methide– where one O is replaced by C
- Xylylene– where both O's are replaced by C's
- Quinone imine – where one O is replaced by N, illustrated byNAPQI
- Quinone diimine – where both O's are replaced by N's, illustrated by the antisepticambazone
- Azaxylylene – where both O's are replaced by one N and one C, illustrated by various fuchsine dyes likepararosaniline
References
[edit]- ^IUPAC,Compendium of Chemical Terminology,2nd ed. (the "Gold Book" ) (1997). Online corrected version: (2006–) "Quinones".doi:10.1351/goldbook.Q05015
- ^Patai, Saul; Rappoport, Zvi, eds. (1988).The Quinonoid Compounds: Vol. 1 (1988).doi:10.1002/9780470772119.ISBN9780470772119.
- ^Patai, Saul; Rappoport, Zvi, eds. (1988).The Quinonoid Compounds: Vol. 2 (1988).doi:10.1002/9780470772126.ISBN9780470772126.
- ^The Chemical News and Journal of Physical Science.Griffin, Bohn and Company. 1773.
- ^Sakurai, T. (1968). "On the refinement of the crystal structures of phenoquinone and monoclinic quinhydrone".Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry.24(3): 403–412.Bibcode:1968AcCrB..24..403S.doi:10.1107/S0567740868002451.
- ^March, Jerry(1985),Advanced Organic Chemistry: Reactions, Mechanisms, and Structure, 3rd edition,New York: Wiley,ISBN9780471854722,OCLC642506595
- ^Guin, Partha Sarathi; Das, Saurabh; Mandal, P. C. (2011-03-16)."Electrochemical Reduction of Quinones in Different Media: A Review".International Journal of Electrochemistry.2011:e816202.doi:10.4061/2011/816202.ISSN2090-3529.
- ^René, Alice; Evans, Dennis H. (2012-07-12)."Electrochemical Reduction of Some o -Quinone Anion Radicals: Why Is the Current Intensity so Small?".The Journal of Physical Chemistry C.116(27): 14454–14460.doi:10.1021/jp3038335.ISSN1932-7447.
- ^Huskinson, Brian; Marshak, Michael P.; Suh, Changwon; Er, Süleyman; Gerhardt, Michael R.; Galvin, Cooper J.; Chen, Xudong; Aspuru-Guzik, Alán; Gordon, Roy G.; Aziz, Michael J. (9 January 2014)."A metal-free organic-inorganic aqueous flow battery"(PDF).Nature.505(7482): 195–198.Bibcode:2014Natur.505..195H.doi:10.1038/nature12909.PMID24402280.S2CID4459692.
- ^abSmith, P. W. G.; Tatchell, A. R. (1969-01-01), Smith, P. W. G.; Tatchell, A. R. (eds.),"Aromatic Alcohols and Carbonyl Compounds",Aromatic Chemistry,Pergamon, pp. 144–175,doi:10.1016/b978-0-08-012948-8.50010-3,ISBN978-0-08-012948-8,retrieved2022-11-17
- ^Nawrat, Christopher C.; Moody, Christopher J. (2014-02-17)."Quinones as Dienophiles in the Diels–Alder Reaction: History and Applications in Total Synthesis".Angewandte Chemie International Edition.53(8): 2056–2077.doi:10.1002/anie.201305908.PMID24446164.S2CID1362687.
- ^Gustaaf Goor, Jürgen Glenneberg, Sylvia Jacobi "Hydrogen Peroxide" in Ullmann's Encyclopedia of Industrial Chemistry 2007, Wiley-VCH, Weinheim.doi:10.1002/14356007.a13_443.pub2.
- ^Braude E. A.; Fawcett, J. S. (1953). "1,4-Naphthoquinone".Organic Syntheses.33:50.doi:10.15227/orgsyn.033.0050;Collected Volumes,vol. 4, p. 698.
- ^abO'Brien, P.J. (1991). "Molecular mechanisms of quinone cytotoxicity".Chemico-Biological Interactions.80(1): 1–41.doi:10.1016/0009-2797(91)90029-7.PMID1913977.
- ^Dorszewska, Jolanta; Prendecki, Michal; Kozubski, Margarita Lianeri and Wojciech (2014-01-31)."Molecular Effects of L-dopa Therapy in Parkinson's Disease".Current Genomics.15(1): 11–17.doi:10.2174/1389202914666131210213042.PMC3958954.PMID24653659.
- ^Liu H., "Extraction and Isolation of Compounds from Herbal Medicines" in 'Traditional Herbal Medicine Research Methods', ed by Willow JH Liu 2011 John Wiley and Sons, Inc.
- ^Dahlin, D. C.; Miwa, G. T.; Lu, A. Y.; Nelson, S. D. (1984)."N-acetyl-p-benzoquinone imine: a cytochrome P-450-mediated oxidation product of acetaminophen".Proceedings of the National Academy of Sciences of the United States of America.81(5): 1327–1331.Bibcode:1984PNAS...81.1327D.doi:10.1073/pnas.81.5.1327.PMC344826.PMID6424115.
- ^Brown, William Henry; Iverson, Brent L.; Anslyn, Eric V.; Foote, Christopher S. (2018).Organic chemistry(8th ed.). Boston, MA: Cengage Learning.ISBN978-1-305-58035-0.OCLC974377227.
External links
[edit]- Quinonesat the U.S. National Library of MedicineMedical Subject Headings(MeSH)
