Furano: Diferenzas entre revisións

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== Historia ==
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TheO namenome ''furanfurano'' comesprocede fromdo the Latin[[latín]] ''furfur'', whichque meanssignifica [[bransalvado]] (de cereais).<ref>Alexander Senning. ''Elsevier's Dictionary of Chemoetymology''. Elsevier, '''2006'''. ISBN 0-444-52239-5.</ref> TheO firstprimeiro furanderivado derivativedo tofurano befoi describeddescrito wascomo [[ácido 2-furoic acidfuroico]], bypor [[Carl Wilhelm Scheele]] inen 1780. AnotherOutro importantimportante derivativederivado, o [[furfural]], wasfoi reporteddescuberto bypor [[Johann Wolfgang Döbereiner]] inen 1831 ande characterisedcaracterizado ninenove yearsanos laterdespois bypor [[John Stenhouse]]. FuranO propio furano foi itselfpreparado waspor firstprimeira preparedvez bypor [[Heinrich Limpricht]] inen 1870, althoughaínda heque calledo itchamou ''tetraphenoltetrafenol''.<ref>{{cite journal | title = Ueber das Tetraphenol C<sub>4</sub>H<sub>4</sub>O | pages = pp.&nbsp;90&ndash;91 | first = H. | last = Limpricht | volume = 3 | issue = 1 | year = 1870 | journal = Berichte der deutschen chemischen Gesellschaft | doi =10.1002/cber.18700030129}}</ref><ref>{{cite book | first = Ernest Harry | last = Rodd | title = Chemistry of Carbon Compounds: A Modern Comprehensive Treatise | publisher = Elsevier | year = 1971}}</ref>
 
==Production Produción ==
Industrially, furan is manufactured by the palladium-catalyzed decarbonylation of [[furfural]], or by the copper-catalyzed oxidation of [[1,3-butadiene]]:<ref name = ullmann>{{Ullmann | doi = 10.1002/14356007.a12_119.pub2 | title = Furfural and Derivatives | author = H. E. Hoydonckx, W. M. Van Rhijn, W. Van Rhijn, D. E. De Vos, P. A. Jacobs}}</ref>
 
IndustriallyIndustrialmente, furano isfurano manufacturedé byfabricado thepor palladium-catalyzedmedio decarbonylationda ofdescarbonilación catalizada por paladio do [[furfural]], orou bypola theoxidación copper-catalyzedcatalizada por oxidationcobre ofdo [[1,3-butadienebutadieno]]:<ref name = ullmann>{{Ullmann | doi = 10.1002/14356007.a12_119.pub2 | title = Furfural and Derivatives | author = H. E. Hoydonckx, W. M. Van Rhijn, W. Van Rhijn, D. E. De Vos, P. A. Jacobs}}</ref>
:[[File:Manufacture of furan.png|450px]]
 
:[[FileFicheiro:Manufacture of furan.png|450px]]
In the laboratory, furan can be obtained from [[furfural]] by oxidation to furan-2-carboxylic acid, followed by decarboxylation.<ref>{{OrgSynth | author = Wilson, W.C. | title = Furan | collvol = 1 | collvolpages = 274 | year = 1941 | prep = cv1p0274}}</ref> It can also be prepared directly by [[thermal decomposition]] of [[pentose]]-containing materials, cellulosic solids especially pine-wood.
 
No laboratorio, o furano pode obterse a partir do furfural por oxidación do ácido furan-2-carboxílico, seguida de descarboxilación.<ref>{{OrgSynth | author = Wilson, W.C. | title = Furan | collvol = 1 | collvolpages = 274 | year = 1941 | prep = cv1p0274}}</ref> Pode tamén prepararse directamente por [[descomposición térmica]] de materiais que conteñan [[pentosa]]s, sóidos celulósicos especialmente madeira de [[piñeiro]].
===Synthesis of furans===
 
=== Síntese de furanos ===
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The [[Feist–Benary synthesis]] is a classic way to synthesize furans, although many syntheses have been developed.<ref>{{cite journal| author = Hou XL, Cheung HY, Hon TY, Kwan PL, Lo TH, Tong SY, Wong HNC| year = 1998 | volume = 54 | pages = 1955–2020 | title = Regioselective syntheses of substituted furans | doi = 10.1016/S0040-4020(97)10303-9 | journal = [[Tetrahedron (journal)|Tetrahedron]]| issue = 10}}</ref> One of the simplest synthesis methods for furans is the reaction of [[ketone|1,4-diketone]]s with [[phosphorus pentoxide]] (P<sub>2</sub>O<sub>5</sub>) in the [[Paal–Knorr synthesis]]. The [[thiophene]] formation reaction of 1,4-diketones with [[Lawesson's reagent]] also forms furans as side products. Many routes exist for the synthesis of substituted furans.<ref>{{cite journal | doi = 10.3998/ark.5550190.0005.208 | title = Synthesis of 2,4-disubstituted furans and 4,6-diaryl-substituted 2,3-benzo-1,3a,6a-triazapentalenes | year = 2003 | last1 = Katritzky | first1 = Alan R. | journal = Arkivoc | volume = 2004 | issue = 2 | pages = 109}}</ref>