Resorcinol (or resorcin) is a phenolic compound. It is an organic compound with the formula C6H4(OH)2. It is one of three isomericbenzenediols, the 1,3-isomer (or meta-isomer). Resorcinol crystallizes from benzene as colorless needles that are readily soluble in water, alcohol, and ether, but insoluble in chloroform and carbon disulfide.[6]
Production
Resorcinol is produced in several steps from benzene, starting with dialkylation with propylene to give 1,3-diisopropylbenzene. Oxidation and Hock rearrangement of this disubstituted arene gives acetone and resorcinol.[6]
Resorcinol is an expensive chemical, produced in only a very few locations around the world (as of 2010 only four commercial plants were known to be operative: in the United States, Germany, China, and Japan), and as such it is the determining factor in the cost of PRF adhesives.[7] Production in the United States ended in 2017 with the closure of Indspec Chemical's plant in Petrolia, Pennsylvania.[8]
Many additional routes exist for resorcinol. It was formerly produced by disulfonation of benzene followed by hydrolysis of the 1,3-disulfonate. This method has been discarded because it cogenerates so much sulfur-containing waste. Resorcinol can also be produced when any of a large number of resins (such as galbanum and asafoetida) are melted with potassium hydroxide, or by the distillation of Brazilwood extract. It may be synthesized by melting 3-iodophenol, phenol-3-sulfonic acid with potassium carbonate. Diazotization of 3-aminophenol or on 1,3-diaminobenzene followed by hydrolysis provides yet another route.[9] Many ortho- and para-compounds of the aromatic series (for example, the bromophenols, benzene-para-disulfonic acid) also yield resorcinol on fusion with potassium hydroxide.
Derivatives of resorcinol are found in different natural sources. Alkylresorcinols are found in rye.[18] Polyresorcinols are found as pseudotannins in plants.[17]
Resorcinol is mainly used in the production of resins. As a mixture with phenol, it condenses with formaldehyde to afford adhesives. Such resins are used as adhesives in the rubber industry and others are used for wood glue.[6] In relation to its conversion resins with formaldehyde, resorcinol is the starting material for resorcinarene rings.
Medical uses
It is present in over-the-counter topical acne treatments at 2% or less concentration, and in prescription treatments at higher concentrations.[19] Monoacetylresorcinol, C6H4(OH)(O–COCH3), is used under the name of Euresol.[20] It is used in hidradenitis suppurativa with limited evidence showing it can help with resolution of the lesions.[21] Resorcinol is one of the active ingredients in products such as Resinol, Vagisil, and Clearasil.
In the 1950s and early 1960s the British Army used it, in the form of a paste applied directly to the skin. One such place where this treatment was given to soldiers with chronic acne was the Cambridge Military Hospital, Aldershot, England. It was not always successful.
Resorcinol is used as a chemical intermediate for the synthesis of pharmaceuticals and other organic compounds. It is used in the production of diazo dyes and plasticizers and as a UV absorber in resins.
It is the starting material for the initiating explosive lead styphnate.[22]
Related compounds
Resazurin, C12H7NO4, obtained by the action of nitrous acid on resorcinol,[23] forms small dark red crystals possessing a greenish metallic glance. When dissolved in concentrated sulfuric acid and warmed to 210 °C, the solution on pouring into water yields a precipitate of resorufin, C12H7NO3, an oxyphenoxazone, which is insoluble in water but is readily soluble in hot concentrated hydrochloric acid, and in solutions of caustic alkalis. The alkaline solutions are of a rose-red color and show a cinnabar-red fluorescence. A tetrabromresorufin is used as a dyestuff under the name of Fluorescent Resorcin Blue.
Thioresorcinol is obtained by the action of zinc and hydrochloric acid on meta-benzenedisulfonyl chloride. It melts at 27 °C and boils at 243 °C. Resorcinol disulfonic acid, (HO)2C6H2(HSO3)2, is a deliquescent mass obtained by the action of sulfuric acid on resorcin.[24] It is readily soluble in water and ethanol.
Austrian chemist Heinrich Hlasiwetz (1825–1875) is remembered for his chemical analysis of resorcinol and for his part in the first preparation of resorcinol, along with Ludwig Barth, which was published in 1864.[27]: 10 [28]
^Gawron, O.; Duggan, M.; Grelechi, C. (1952). "Manometric Determination of Dissociation Constants of Phenols". Analytical Chemistry. 24 (6): 969–970. doi:10.1021/ac60066a013.
^ abcdCRC handbook of chemistry and physics: a ready-reference book of chemical and physical data. William M. Haynes, David R. Lide, Thomas J. Bruno (2016-2017, 97th ed.). Boca Raton, Florida. 2016. ISBN978-1-4987-5428-6. OCLC930681942.{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
^Lander, John J.; Svirbely, John J. Lander, W. J. (1945). "The Dipole Moments of Catechol, Resorcinol and Hydroquinone". Journal of the American Chemical Society. 67 (2): 322–324. Bibcode:1945JAChS..67..322L. doi:10.1021/ja01218a051.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Boer, J; Jemec, GB (2010). "Resorcinol peels as a possible self-treatment of painful nodules in hidradenitis suppurativa". Clinical and Experimental Dermatology. 35 (1): 36–40. doi:10.1111/j.1365-2230.2009.03377.x. PMID19549239. S2CID1794323.
^Wipperman, J; Bragg, DA; Litzner, B (1 November 2019). "Hidradenitis Suppurativa: Rapid Evidence Review". American Family Physician. 100 (9): 562–569. PMID31674740.
^"Military Explosives," Department of the Army Technical Manual, TM-9-1300-214 (Washington, D.C.: Department of the Army, September 1984), p. 7-12.
^ abSidera, K.; Patsavoudi, E. (January 2014). "HSP90 inhibitors: current development and potential in cancer therapy". Recent Patents on Anti-Cancer Drug Discovery. 9 (1): 1–20. doi:10.2174/15748928113089990031. PMID23312026.
^Biamonte, M. A.; Van de Water, R.; Arndt, J. W.; Scannevin, R. H.; Perret, D.; Lee, W.-C. (January 2010). "Heat shock protein 90: Inhibitors in clinical trials". Journal of Medicinal Chemistry. 53 (1): 3–17. doi:10.1021/jm9004708. PMID20055425.
^Raj B. Durairaj. Resorcinol: Chemistry, Technology and Applications. Springer Science & Business Media, 2005 ISBN9783540280903
^McConnell, Virginia F. (1953). "Hlasiwetz and Barth — Pioneers in the structural aspects of plant products". Journal of Chemical Education. 30 (8): 380. Bibcode:1953JChEd..30..380M. doi:10.1021/ed030p380.
^Panico, R.; & Powell, W. H. (Eds.) (1994). A Guide to IUPAC Nomenclature of Organic Compounds 1992. Oxford: Blackwell Science. ISBN978-0-632-03488-8.{{cite book}}: CS1 maint: multiple names: authors list (link)
^H. Hlasiwetz and L. Barth (1864) "Ueber einen neuen, dem Orcin homologen Körper" (On a new substance homologous to orcin), Annalen der Chemie, 130 (3) : 354-359. Resorcinol is named on p. 358: "Wir nennen den neuen Körper, da wir gefunden haben, dass er auch aus dem Ammoniakgummiharz erhalten werden kann, Resorcin, um an seine Entstehung aus Harzen und seine Beziehung zum Orcin zu erinnern." (We name the new substance, since we have found that it can be obtained from ammoniated resin gum, resorcin, in order to recall its creation from resin and its relation to orcin.)