Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Butadiene: Difference between pages

{{redirect|Divinyl|the band|Divinyls}}

{{Use dmy dates|date=December 2020}}

|Watchedfields = changed

|verifiedrevid = 477205044

|Name = 1,3-Butadiene

|ImageFileL1 = Butadiène.PNG

|ImageNameL1 = Full structural formula of 1,3-butadiene

|ImageSizeL1 = 90px

|ImageFileR1 = Butadiene-skeletal.png

|ImageNameR1 = Skeletal formula of 1,3-butadiene

|ImageSizeR1 = 130px

|ImageFileL2 = Trans-butadiene-3D-balls.png

|ImageNameL2 = Ball-and-stick model of 1,3-butadiene

|ImageSizeL2 = 90px

|ImageFileR2 = Buta-1,3-diene-3D-vdW.png

|ImageNameR2 = Space-filling model of 1,3-butadiene

|ImageSizeR2 = 130px

|PIN = Buta-1,3-diene<ref name=iupac2013>

{{cite book

| title = Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book)

| publisher = [[Royal Society of Chemistry|The Royal Society of Chemistry]]

| date =2014

| location = Cambridge

| page = 374

| doi = 10.1039/9781849733069-FP001

| isbn = 978-0-85404-182-4

| chapter = Front Matter

}}</ref>

|OtherNames = {{ubl

| Biethylene

| Erythrene

| Divinyl

| Vinylethylene

| Bivinyl

| Butadiene

|data page pagename = none

|Section1={{Chembox Identifiers

|UNII_Ref = {{fdacite|correct|FDA}}

|UNII = JSD5FGP5VD

|SMILES = C=CC=C

|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

|ChEBI_Ref = {{ebicite|correct|EBI}}

|ChEBI = 39478

|ChemSpiderID = 7557

|KEGG_Ref = {{keggcite|correct|kegg}}

|KEGG = C16450

|InChI = 1/C4H6/c1-3-4-2/h3-4H,1-2H2

|InChIKey = KAKZBPTYRLMSJV-UHFFFAOYAZ

|ChEMBL_Ref = {{ebicite|correct|EBI}}

|ChEMBL = 537970

|StdInChI_Ref = {{stdinchicite|correct|chemspider}}

|StdInChI = 1S/C4H6/c1-3-4-2/h3-4H,1-2H2

|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|StdInChIKey = KAKZBPTYRLMSJV-UHFFFAOYSA-N

|CASNo_Ref = {{cascite|correct|CAS}}

|CASNo = 106-99-0

|UNNumber = [[List of UN Numbers 1001 to 1100|1010]]

|RTECS = EI9275000

|PubChem = 7845

|EINECS = 271-039-0

|Gmelin = 25198

|Beilstein = 605258

|Section2={{Chembox Properties

|Properties_ref = <ref>{{cite web |title=1,3-Butadiene |url=http://webbook.nist.gov/cgi/cbook.cgi?ID=106-99-0&Units=SI |website=NIST Chemistry WebBook}}</ref>

|Formula = C₄H₆<br/>CH₂=CH-CH=CH₂

|MolarMass = 54.0916 g/mol

|Appearance = Colourless gas<br /> or refrigerated liquid

|Odor = Mildly aromatic or gasoline-like

|Density = {{ubl

| 0.6149{{nbsp}}g/cm³ at 25&nbsp;°C, p>1 atm<ref name="crc97">{{cite book |first=William M. |last=Haynes |title=CRC Handbook of Chemistry and Physics |edition=97th |year=2016 |publisher=CRC Press |location=Boca Raton |isbn=978-1-4987-5429-3 |page=3-76 |url=https://books.google.com/books?id=VVezDAAAQBAJ}}</ref>

| 0.64{{nbsp}}g/cm³ at −6&nbsp;°C, liquid

|Solubility = 1.3{{nbsp}}g/L at 5{{nbsp}}°C, 735{{nbsp}}mg/L at 20{{nbsp}}°C

|SolubleOther = {{ubl

| Very soluble in [[acetone]]

| Soluble in [[diethyl ether|ether]], [[ethanol]]

|MeltingPtC = −108.91

|BoilingPtC = −4.41

|Viscosity = 0.25{{nbsp}}c[[Poise (unit)|P]] at 0&nbsp;°C

|RefractIndex = 1.4292

|VaporPressure = 2.4{{nbsp}}atm (20{{nbsp}}°C)<ref name=PGCH/>

|Section3={{Chembox Hazards

|ExternalSDS = [http://www.inchem.org/documents/icsc/icsc/eics0017.htm ECSC 0017]

|MainHazards = Flammable, irritative, [[carcinogen]]

|FlashPtC = −85

|FlashPt_notes = liquid flash point<ref name=PGCH/>

|AutoignitionPtC = 414

|AutoignitionPt_ref = <ref>{{cite web |website=INCHEM |url=https://inchem.org/documents/icsc/icsc/eics0017.htm |title=1,3-Butadiene |publisher=International Programme on Chemical Safety (IPCS)}}</ref>

|ExploLimits = 2–12%

|GHS_ref = <ref>{{GESTIS|ZVG=11430}}</ref>

|GHSPictograms = {{GHS02}} {{GHS08}} {{GHS04}}

|GHSSignalWord = Danger

|HPhrases = {{H-phrases|H220|H280|H340|H350}}

|PPhrases = {{P-phrases|P202|P210|P280|P308+P313|P377|P381|P403}}

|NFPA-H = 3 | NFPA-F = 4 | NFPA-R = 2

|LD50 = 548{{nbsp}}mg/kg (rat, oral)

|PEL = TWA 1{{nbsp}}ppm ST 5{{nbsp}}ppm<ref name=PGCH>{{PGCH|0067}}</ref>

|IDLH = 2000{{nbsp}}ppm<ref name=PGCH/>

|REL = Potential occupational carcinogen<ref name=PGCH/>

|LC50 = {{ubl

| 115,111{{nbsp}}ppm (mouse)

| 122,000{{nbsp}}ppm (mouse, 2{{nbsp}}[[hour|h]])

| 126,667{{nbsp}}ppm (rat, 4{{nbsp}}h)

| 130,000{{nbsp}}ppm (rat, 4{{nbsp}}h)<ref name=IDLH>{{IDLH|106990|1,3-Butadiene}}</ref>

| LCLo = 250,000{{nbsp}}ppm (rabbit, 30{{nbsp}}min)<ref name=IDLH/>

}}

|Section4={{Chembox Related

|OtherFunction_label = [[Alkenes]]<br /> and [[diene]]s

|OtherFunction = [[Isoprene]]<br />[[Chloroprene]]

|OtherCompounds = [[Butane]]

}}

}}

'''1,3-Butadiene''' ({{IPAc-en|ˌ|b|juː|t|ə|ˈ|d|aɪ|iː|n}})<ref>{{cite web |url=https://www.lexico.com/definition/butadiene |archive-url=https://web.archive.org/web/20200820020023/https://www.lexico.com/definition/butadiene |url-status=dead |archive-date=20 August 2020 |title=BUTADIENE &#124; Meaning & Definition for UK English |publisher=Lexico.com |date= |accessdate=2022-08-24}}</ref> is the [[organic compound]] with the formula CH₂=CH-CH=CH₂. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to [[synthetic rubber]].<ref name=":0">{{Cite web |last=PubChem |title=1,3-Butadiene |url=https://pubchem.ncbi.nlm.nih.gov/compound/7845 |access-date=2024-05-08 |website=pubchem.ncbi.nlm.nih.gov |language=en}}</ref> The molecule can be viewed as the union of two [[vinyl group]]s. It is the simplest [[conjugated diene]].

Although butadiene [[chemical degradation|breaks down]] quickly in the atmosphere, it is nevertheless found in ambient air in urban and suburban areas as a consequence of its constant [[Exhaust gas|emission]] from [[motor vehicle]]s.<ref>{{cite web|url=http://www.epa.gov/ttn/atw/hlthef/butadien.html |title=1,3-Butadiene|publisher=US Environmental Protection Agency [[US EPA]]|access-date=2014-09-02}}</ref>

The name butadiene can also refer to the [[isomer]], [[1,2-butadiene]], which is a [[diene|cumulated diene]] with structure H₂C=C=CH−CH₃. This [[allene]] has no industrial significance.

==History==

In 1863, French chemist E. Caventou isolated butadiene from the [[pyrolysis]] of [[amyl alcohol]].<ref name=Caventou>{{cite journal |last=Caventou |first=E. |year=1863 |journal=Justus Liebigs Annalen der Chemie |volume=127 |pages=93–97 |title=Ueber eine mit dem zweifach-gebromten Brombutylen isomere Verbindung und über die bromhaltigen Derivate des Brombutylens |doi=10.1002/jlac.18631270112 |url=https://zenodo.org/record/1427203}}</ref> This hydrocarbon was identified as butadiene in 1886, after [[Henry Edward Armstrong]] isolated it from among the pyrolysis products of petroleum.<ref name=Armstrong>{{cite journal |last1=Armstrong |first1=H. E. |last2=Miller |first2=A. K. |year=1886 |title=The decomposition and genesis of hydrocarbons at high temperatures. I. The products of the manufacture of gas from petroleum |journal=J. Chem. Soc. |volume=49 |pages=74–93 |doi=10.1039/CT8864900074| url=https://zenodo.org/record/1716439}}</ref> In 1910, the Russian chemist [[Sergei Vasilyevich Lebedev|Sergei Lebedev]] polymerized butadiene and obtained a material with rubber-like properties. This polymer was, however, found to be too soft to replace natural rubber in many applications, notably automobile tires.

The butadiene industry originated in the years before World War II. Many of the belligerent nations realized that in the event of war, they could be cut off from rubber plantations controlled by the [[British Empire]], and sought to reduce their dependence on natural rubber.<ref>[https://books.google.com/books?id=7yHlAgAAQBAJ&dq=butadiene+dependence+on+natural+rubber&pg=PA23 Simple Things Won't Save the Earth], J. Robert Hunter</ref> In 1929, [[Eduard Tschunker]] and [[Walter Bock]], working for [[IG Farben]] in Germany, made a copolymer of [[styrene]] and butadiene that could be used in automobile tires. Worldwide production quickly ensued, with butadiene being produced from [[ethanol|grain alcohol]] in the Soviet Union and the United States, and from coal-derived [[acetylene]] in Germany.

==Production==

In 2020, 14.2 million tons were estimated to have been produced.<ref name=Beller>{{cite journal |doi=10.1039/D3IM00009E |title=Industrially applied and relevant transformations of 1,3-butadiene using homogeneous catalysts |date=2023 |last1=Yang |first1=Ji |last2=Wang |first2=Peng |last3=Neumann |first3=Helfried |last4=Jackstell |first4=Ralf |last5=Beller |first5=Matthias |journal=Industrial Chemistry & Materials |volume=1 |issue=2 |pages=155–174 |s2cid=258122761 |doi-access=free }}</ref>

===Extraction from C₄ hydrocarbons===

In the United States, western Europe, and Japan, butadiene is produced as a byproduct of the [[steam cracking]] process used to produce [[ethylene]] and other [[alkene]]s. When mixed with steam and briefly heated to very high temperatures (often over 900&nbsp;°C), aliphatic hydrocarbons give up hydrogen to produce a complex mixture of unsaturated hydrocarbons, including butadiene. The quantity of butadiene produced depends on the hydrocarbons used as feed. Light feeds, such as [[ethane]], give primarily [[ethylene]] when cracked, but heavier feeds favor the formation of heavier olefins, butadiene, and [[aromatic hydrocarbon]]s.

Butadiene is typically isolated from the other four-carbon [[hydrocarbon]]s produced in steam cracking by extractive distillation using a [[polar aprotic solvent]] such as [[acetonitrile]], [[N-Methyl-2-pyrrolidone|''N''-methyl-2-pyrrolidone]], [[furfural]], or [[dimethylformamide]], from which it is then stripped by [[distillation]].<ref name=ECT4thEd>Sun, H.P. Wristers, J.P. (1992). Butadiene. In J.I. Kroschwitz (Ed.), ''Encyclopedia of Chemical Technology, 4th ed.'', vol. 4, pp. 663–690. New York: John Wiley & Sons.</ref>

===From dehydrogenation of ''n''-butane===

Butadiene can also be produced by the catalytic [[dehydrogenation]] of normal butane (''n''-butane). The first such post-war commercial plant, producing 65,000 [[ton]]s per year of butadiene, began operations in 1957 in [[Houston]], Texas.<ref name=Beychok>Beychok, M.R. and Brack, W.J., "First Postwar Butadiene Plant", ''Petroleum Refiner'', June 1957.</ref> Prior to that, in the 1940s the [[Rubber Reserve Company]], a part of the United States government, constructed several plants in [[Borger, Texas]], [[Toledo, Ohio]], and [[El Segundo, California]], to produce synthetic rubber for the war effort as part of the United States Synthetic Rubber Program.<ref name=Herbert>{{cite book |last=Herbert |first=Vernon |title=Synthetic Rubber: A Project That Had to Succeed |publisher=Greenwood Press |year=1985 |isbn=0-313-24634-3}}</ref> Total capacity was 68 KMTA (Kilo Metric Tons per Annum).

Today, butadiene from ''n''-butane is commercially produced using the '''Houdry Catadiene process''', which was developed during World War II. This entails treating butane over [[alumina]] and [[Chromium(III) oxide|chromia]] at high temperatures.<ref name=Ullmann>{{Ullmann |title=Butadiene |first1=J. |last1=Grub |first2=E. |last2=Löser |year=2012 |doi=10.1002/14356007.a04_431.pub2}}</ref>

===From ethanol===

In other parts of the world, including South America, Eastern Europe, China, and India, butadiene is also produced from [[ethanol]]. While not competitive with steam cracking for producing large volumes of butadiene, lower capital costs make production from ethanol a viable option for smaller-capacity plants. Two processes were in use.

In the single-step process developed by [[Sergei Vasilyevich Lebedev|Sergei Lebedev]], ethanol is converted to butadiene, hydrogen, and water at 400–450&nbsp;°C over any of a variety of metal oxide catalysts:<ref name=ECT3rdEd>{{cite book |last=Kirshenbaum |first=I. |year=1978 |chapter=Butadiene |editor-first=M. |editor-last=Grayson |title=Encyclopedia of Chemical Technology |edition=3rd |volume=4 |pages=313–337 |place=New York |publisher=John Wiley & Sons}}</ref>

:[[File:Lebedev.svg|500px|thumb|none|2 [[ethanol|CH₃CH₂OH]] → CH₂=CH−CH=CH₂ + 2 [[water|H₂O]] + [[hydrogen|H₂]]]]

This process was the basis for the [[Soviet Union]]'s synthetic rubber industry during and after World War II, and it remained in limited use in Russia and other parts of eastern Europe until the end of the 1970s. At the same time this type of manufacture was canceled in Brazil. As of 2017, no butadiene was produced industrially from ethanol.

In the other, two-step process, developed by the Russian emigre chemist [[Ivan Ostromislensky]], ethanol is [[oxidation|oxidized]] to [[acetaldehyde]], which reacts with additional ethanol over a [[tantalum]]-promoted porous [[silica]] catalyst at 325–350&nbsp;°C to yield butadiene:<ref name=ECT3rdEd/>

:[[File:Ostromislensky reaction.png|400px|thumb|none|CH₃CH₂OH + CH₃CHO → CH₂=CH−CH=CH₂ + 2 H₂O

]]

This process was one of the three used in the United States to produce "government rubber" during World War II, although it is less economical than the butane or butene routes for the large volumes. Still, three plants with a total capacity of 200,000 tons per year were constructed in the U.S. ([[Institute, West Virginia]], [[Louisville, Kentucky]], and [[Kobuta, Pennsylvania]]) with start-ups completed in 1943, the Louisville plant initially created butadiene from acetylene generated by an associated calcium carbide plant. The process remains in use today in China and India.

===From butenes===

1,3-Butadiene can also be produced by [[catalytic]] [[dehydrogenation]] of normal [[butene]]s. This method was also used by the [[U.S. Synthetic Rubber Program]] (USSRP) during [[World War II]]. The process was much more economical than the alcohol or n-butane route but competed with [[aviation gasoline]] for available butene molecules (butenes were plentiful thanks to [[catalytic cracking]]). The USSRP constructed several plants in [[Baton Rouge, Louisiana|Baton Rouge]] and [[Lake Charles, Louisiana]]; [[Houston]], [[Baytown, Texas|Baytown]], and [[Port Neches, Texas]]; and [[Torrance, California]].<ref name="Herbert"/> Total annual production was 275 KMTA.

In the 1960s, a [[Houston]] company known as "Petro-Tex" patented a process to produce butadiene from normal [[butene]]s by oxidative [[dehydrogenation]] using a proprietary catalyst. It is unclear if this technology is practiced commercially.<ref>{{cite journal |last1=Welch |first1=L. Marshall |last2=Croce |first2=Louis |last3=Christmann |first3=Harold |date=November 1978 |url=https://www.researchgate.net/publication/285448537 |title=BUTADIENE VIA OXIDATIVE DEHYDROGENATION |access-date=2019-06-01 |journal=Hydrocarbon Processing |volume=57 |issue=11 |pages=131–136 |via=ResearchGate}}</ref>

After World War II, the production from butenes became the major type of production in USSR.

===For laboratory use===

1,3-Butadiene is inconvenient for laboratory use because it is gas. Laboratory procedures have been optimized for its generation from nongaseous precursors. It can be produced by the retro-[[Diels-Alder reaction]] of [[cyclohexene]].<ref>{{cite journal |title=1,3-Butadiene|first1=E. B. |last1=Hershberg |first2=John R. |last2=Ruhoff |journal=Org. Synth. |year=1937 |volume=17 |page=25 |doi=10.15227/orgsyn.017.0025}}</ref> [[Sulfolene]] is a convenient solid storable source for 1,3-butadiene in the laboratory. It releases the diene and [[sulfur dioxide]] upon heating.

==Uses==

Most butadiene(75% of the manufactured 1,3-butadiene<ref name=":0" />) is used to make synthetic rubbers for the manufacture of tyres and components of many consumer items.

The conversion of butadiene to synthetic rubbers is called [[polymerization]], a process by which small molecules (monomers) are linked to make large ones (polymers). The mere polymerization of butadiene gives [[polybutadiene]], which is a very soft, almost liquid material. The polymerization of butadiene ''and'' other monomers gives [[copolymer]]s, which are more valued. The polymerization of butadiene and [[styrene]] and/or [[acrylonitrile]], such as [[acrylonitrile butadiene styrene]] (ABS), [[Nitrile rubber|nitrile-butadiene]] (NBR), and [[styrene-butadiene]] (SBR). These copolymers are tough and/or elastic depending on the ratio of the monomers used in their preparation. SBR is the material most commonly used for the production of automobile tyres. Precursors to still other synthetic rubbers are prepared from butadiene. One is [[chloroprene]].<ref name=Ullmann/>

Smaller amounts of butadiene are used to make [[adiponitrile]], a precursor to some nylons. The conversion of butadiene to adiponitrile entails the addition of [[hydrogen cyanide]] to each of the double bonds in butadiene. The process is called [[hydrocyanation]].

Butadiene is used to make the solvent [[sulfolane]].

Butadiene is also useful in the synthesis of [[cycloalkanes]] and [[cycloalkenes]], as it reacts with double and triple carbon-carbon bonds through [[Diels-Alder reaction]]s. The most widely used such reactions involve reactions of butadiene with one or two other molecules of butadiene, i.e., dimerization and trimerization respectively. Via dimerization butadiene is converted to [[4-vinylcyclohexene]] and [[cyclooctadiene]]. In fact, vinylcyclohexene is a common impurity that accumulates when butadiene is stored. Via trimerization, butadiene is converted to [[cyclododecatriene]]. Some of these processes employ nickel- or titanium-containing catalysts.<ref name="iarc">{{cite book |url=http://monographs.iarc.fr/ENG/Monographs/vol60/mono60-13.pdf |title=4-Vinylcyclohexene |access-date=2009-04-19 |publisher=IARC |isbn=9789283212607}}</ref>

Butadiene is also a precursor to [[1-octene]] via palladium catalyzed [[telomerization]] with methanol. This reaction produces 1-methoxy-

2,7-octadiene as an intermediate.<ref name=Beller/>

== Structure, conformation, and stability ==

[[File:Comparison of butadiene and ethylene.png|left|thumb|400px|Comparison of butadiene (''s-trans'' conformer) and ethylene]]

The most stable [[Conformational isomerism|conformer]] of 1,3-butadiene is the ''s''-''trans'' conformation, in which the molecule is planar, with the two pairs of double bonds facing opposite directions. This conformation is most stable because orbital overlap between double bonds is maximized, allowing for maximum conjugation, while steric effects are minimized. Conventionally, the ''s-trans'' conformation is considered to have a C₂-C₃ dihedral angle of 180°. In contrast, the ''s''-''cis'' conformation, in which the dihedral angle is 0°, with the pair of double bonds facing the same direction is approximately 16.5 kJ/mol (3.9 kcal/mol) higher in energy, due to steric hindrance. This geometry is a local energy maximum, so in contrast to the ''s-trans'' geometry, it is not a conformer. The ''gauche'' geometry, in which the double bonds of the ''s-cis'' geometry are twisted to give a dihedral angle of around 38°, is a second conformer that is around 12.0 kJ/mol (2.9 kcal/mol) higher in energy than the ''s-trans'' conformer. Overall, there is a barrier of 24.8 kJ/mol (5.9 kcal/mol) for isomerization between the two conformers.<ref>{{Cite journal |last1=Feller |first1=David |last2=Craig |first2=Norman C. |date=2009-02-26 |title=High Level ab Initio Energies and Structures for the Rotamers of 1,3-Butadiene |journal=The Journal of Physical Chemistry A |volume=113 |issue=8 |pages=1601–1607 |doi=10.1021/jp8095709 |issn=1089-5639 |pmid=19199679 |bibcode=2009JPCA..113.1601F}}</ref> This increased rotational barrier and strong overall preference for a near-planar geometry is evidence for a delocalized π system and a small degree of partial double bond character in the C–C single bond, in accord with resonance theory.

Despite the high energy of the ''s-cis'' conformation, 1,3-butadiene needs to assume this conformation (or one very similar) before it can participate as the four-electron component in concerted cycloaddition reactions like the [[Diels–Alder reaction|Diels-Alder reaction]].

Similarly, a combined experimental and computational study has found that the double bond of ''s-trans-''butadiene has a length of 133.8&nbsp;pm, while that for ethylene has a length of 133.0&nbsp;pm. This was taken as evidence of a π-bond weakened and lengthened by delocalization, as depicted by the resonance structures shown below.<ref>{{Cite journal |last1=Craig |first1=Norman C. |last2=Groner |first2=Peter |last3=McKean |first3=Donald C. |date=2006-06-01 |title=Equilibrium Structures for Butadiene and Ethylene: Compelling Evidence for Π-Electron Delocalization in Butadiene |journal=The Journal of Physical Chemistry A |volume=110 |issue=23 |pages=7461–7469 |doi=10.1021/jp060695b |pmid=16759136 |bibcode=2006JPCA..110.7461C |issn=1089-5639}}</ref>

[[File:Butadiene-resonance.png|center|frameless|500px]]

A qualitative picture of the [[molecular orbital]]s of 1,3-butadiene is readily obtained by applying Hückel theory. (The article on [[Hückel method|Hückel theory]] gives a derivation for the butadiene orbitals.)

1,3-Butadiene is also thermodynamically stabilized. While a monosubstituted double bond releases about 30.3 kcal/mol of heat upon hydrogenation, 1,3-butadiene releases slightly less (57.1 kcal/mol) than twice this energy (60.6 kcal/mol), expected for two isolated double bonds. That implies a stabilization energy of 3.5 kcal/mol.<ref>{{Cite book|title=Organic chemistry: structure and function |first1=K. Peter C.|last1=Vollhardt|date=2007|publisher=W.H. Freeman|last2=Schore |first2=Neil Eric |isbn=978-0716799498 |edition=5th |location=New York|oclc=61448218}}</ref> Similarly, the hydrogenation of the terminal double bond of 1,4-pentadiene releases 30.1 kcal/mol of heat, while hydrogenation of the terminal double bond of conjugated (''E'')-1,3-pentadiene releases only 26.5 kcal/mol, implying a very similar value of 3.6 kcal/mol for the stabilization energy.<ref>{{Cite book |title=Organic chemistry |last=Carey |first=Francis A. |date=2002 |publisher=McGraw-Hill |isbn=978-0071151498 |edition=5th |location=London |oclc=49907089}}</ref> The ~3.5 kcal/mol difference in these heats of hydrogenation can be taken to be the resonance energy of a conjugated diene.

==Reactions==

[[Image:(Butadiene)iron-tricarbonyl-3D-balls.png|thumb|right|The structure of [[(Butadiene)iron tricarbonyl|(butadiene)iron tricarbonyl]]<ref>{{cite journal|title=Redetermination of (η⁴-s-cis-1,3-butadiene)tricarbonyliron(0)

|last=Reiss |first=Guido J.

|journal=Acta Crystallographica Section E

|year=2010

|volume=66

|issue=11

|pages=m1369|doi=10.1107/S1600536810039218|pmid=21588810

|pmc=3009352|bibcode=2010AcCrE..66m1369R }}</ref>]]

The industrial uses illustrate the tendency of butadiene to polymerize. Its susceptibility to 1,4-addition reactions is illustrated by its hydrocyanation. Like many dienes, it undergoes Pd-catalyzed reactions that proceed via allyl complexes.<ref>{{cite journal |title=1,4-Functionalization of 1,3-Dienes via Palladium-Catalyzed Chloroacetoxylation and Allylic Amination: 1-Acetoxy-4-diethylamino-2-butene and 1-Acetoxy-4-benzylamino-2-butene|first1=J. E. |last1=Nyström |first2=T. |last2=Rein |first3=J. E. |last3=Bäckvall |journal=Org. Synth. |year=1989 |volume=67 |page=105 |doi=10.15227/orgsyn.067.0105}}</ref> It is a partner in [[Diels–Alder reaction|Diels–Alder reactions]], e.g. with maleic anhydride to give [[tetrahydrophthalic anhydride]].<ref>{{cite journal|title=cis-Δ4-Tetrahydrophthalic Anhydride|first1=Arthur C. |last1=Cope |first2=Elbert C. |last2=Herrick |journal=Org. Synth. |year=1950 |volume=50 |page=93 |doi=10.15227/orgsyn.030.0093}}</ref>

Like other dienes, butadiene is a ligand for low-valent metal complexes, e.g. the derivatives Fe(butadiene)(CO)₃ and Mo(butadiene)₃.

==Environmental health and safety==

[[File:Placard 1010.jpg|left|thumb|A railway [[tank car]] carrying a butadiene and [[hydrocarbon]] mixture, displaying [[hazardous materials]] information including a diamond-shaped [[Placard#United States Department of Transportation|U.S. DOT placard]] showing a [[UN number]]<ref name=":0" />]]

Butadiene is of low acute toxicity. [[LC50]] is 12.5–11.5 vol% for inhalation by rats and mice.<ref name=Ullmann/>

Long-term exposure has been associated with cardiovascular disease. There is a consistent association with leukemia, as well as a significant association with other cancers.<ref name="EPA">{{cite web |title=NPI sheet |url=http://www.npi.gov.au/database/substance-info/profiles/16.html |access-date=10 January 2006 |archive-url=https://web.archive.org/web/20031222084351/http://www.npi.gov.au/database/substance-info/profiles/16.html#health |archive-date=22 December 2003 |url-status=dead}}</ref>

[[International Agency for Research on Cancer|IARC]] has designated 1,3-butadiene as a [[List of IARC Group 1 Agents - Carcinogenic to humans|Group 1]] [[carcinogen]] ('carcinogenic to humans'),<ref>{{Cite journal |last1=Grosse |first1=Yann |last2=Baan |first2=Robert |last3=Straif |first3=Kurt |last4=Secretan |first4=Béatrice |last5=El Ghissassi |first5=Fatiha |last6=Bouvard |first6=Véronique |last7=Altieri |first7=Andrea |last8=Cogliano |first8=Vincent |date=2008 |title=Carcinogenicity of 1,3-butadiene, ethylene oxide, vinyl chloride, vinyl fluoride, and vinyl bromide |journal=The Lancet Oncology |volume=8 |issue=8 |pages=679–680 |doi=10.1016/S1470-2045(07)70235-8 |pmid=17726789 |issn=1470-2045}}</ref> and the Agency for Toxic Substances Disease Registry and the US EPA also list the chemical as a carcinogen.<ref>{{cite web |url=https://wwwn.cdc.gov/TSP/index.aspx?toxid=81 |publisher=Agency for Toxic Substances and Disease Registry (ATSDR) |website=Toxic Substances Portal |title=1,3-Butadiene |url-status=live |archive-url=https://web.archive.org/web/20120609034438/http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=81 |archive-date=2012-06-09}}</ref><ref name="osha.gov">{{cite web |title=1,3-Butadiene: Health Effects |publisher=Occupational Safety & Health Administration |url=https://www.osha.gov/butadiene/health-effects}}</ref> The American Conference of Governmental Industrial Hygienists (ACGIH) lists the chemical as a suspected carcinogen.<ref name="osha.gov"/> The Natural Resource Defense Council (NRDC) lists some [[Disease cluster|disease clusters]] that are suspected to be associated with this chemical.<ref>{{cite web |date=May 10, 2011 |url=http://www.nrdc.org/health/diseaseclusters/ |title=Disease Clusters Spotlight the Need to Protect People from Toxic Chemicals |publisher=NRDC}}</ref> Some researchers have concluded it is the most potent carcinogen in [[cigarette smoke]], twice as potent as the runner up [[acrylonitrile]]<ref>{{cite journal |last1=Fowles |first1=J. |last2=Dybing |first2=E. |title=Application of toxicological risk assessment principles to the chemical constituents of cigarette smoke|journal=Institute of Environmental Science and Research |date=4 September 2003 |pages=424–430 |pmc=1747794 |pmid=14660781 |volume=12 |issue=4 |doi=10.1136/tc.12.4.424}}</ref>

1,3-Butadiene is also a suspected human [[teratogen]].<ref>{{cite journal |pmc=1567758 |year=1990 |last1=Landrigan |first1=P. J. |title=Critical assessment of epidemiologic studies on the human carcinogenicity of 1,3-butadiene |volume=86 |pages=143–147 |journal=Environmental Health Perspectives |doi=10.1289/ehp.9086143 |pmid=2205484}}</ref><ref>{{cite journal |title=1,3-Butadiene CAS No. 106-99-0 |url=https://ntp.niehs.nih.gov/ntp/roc/content/profiles/butadiene.pdf |journal=Report on Carcinogens |archive-url=https://web.archive.org/web/20090508210250/http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s025buta.pdf |archive-date=2009-05-08 |url-status=live |edition=11th}}</ref><ref>{{cite journal |doi=10.1093/carcin/16.2.157 |title=Mechanistic data indicate that 1,3-butadiene is a human carcinogen |year=1995 |last1=Melnick |first1=Ronald L. |last2=Kohn |first2=Michael C. |journal=Carcinogenesis |volume=16 |issue=2 |pages=157–163 |pmid=7859343| url=https://zenodo.org/record/1234301}}</ref> Prolonged and excessive exposure can affect many areas in the human body; blood, brain, eye, heart, kidney, lung, nose and throat have all been shown to react to the presence of excessive 1,3-butadiene.<ref>{{cite web |url=http://www.environment-agency.gov.uk/business/topics/pollution/27.aspx |access-date=20 August 2010 |title=Environment Agency - 1,3-Butadiene |archive-date=3 February 2011 |archive-url=https://web.archive.org/web/20110203013835/http://www.environment-agency.gov.uk/business/topics/pollution/27.aspx |url-status=dead}}</ref> Animal data suggest that women have a higher sensitivity to possible carcinogenic effects of butadiene over men when exposed to the chemical. This may be due to estrogen receptor impacts. While these data reveal important implications to the risks of human exposure to butadiene, more data are necessary to draw conclusive risk assessments. There is also a lack of human data for the effects of butadiene on reproductive and development shown to occur in mice, but animal studies have shown breathing butadiene during pregnancy can increase the number of birth defects, and humans have the same hormone systems as animals.<ref>{{cite web |title=1,3-Butadiene |website=Technology Transfer Network Air Toxics Web Site |url=http://www.epa.gov/ttn/atw/hlthef/butadien.html |publisher=EPA |archive-date=2012-05-11 |archive-url=https://web.archive.org/web/20120511015414/http://www.epa.gov/ttn/atw/hlthef/butadien.html |url-status=dead}}</ref>

1,3-Butadiene is recognized as a highly reactive [[volatile organic compound]] (HRVOC) for its potential to readily form [[ozone]], and as such, emissions of the chemical are highly regulated by [[Texas Commission on Environmental Quality|TCEQ]] in parts of the [[Greater Houston|Houston-Brazoria-Galveston]] [[Non-Attainment Area|Ozone Non-Attainment Area]].<ref>{{cite web |title=Controlling HRVOC Emissions |publisher=Texas Commission on Environmental Quality |url=https://www.tceq.texas.gov/airquality/stationary-rules/voc/hrvoc.html}}</ref>

==Data sheet==

{| class="wikitable floatleft" style="font-size:90%; width:300px;"

|+

! {{Chemical datatable header}} | <span style="font-size:130%;">Properties</span>

|-

! {{Chemical datatable header}} | Phase behavior

|-

| [[Triple point]] || 164.2 K (-109.0&nbsp;°C)<br>

? [[bar (unit)|bar]]

|-

| [[Critical point (thermodynamics)|Critical point]] || 425 K (152&nbsp;°C)<br>

43.2 [[bar (unit)|bar]]

|-

! {{Chemical datatable header}} | Structure

|-

| [[Symmetry group]] || C_2h

|-

! {{Chemical datatable header}} | Gas properties

|-

| Δ_fH⁰ || 110.2 kJ/mol

|-

| [[Heat capacity|C_p]] || 79.5 J/mol·K

|-

! {{Chemical datatable header}} | Liquid properties

|-

| Δ_fH⁰ || 90.5 kJ/mol

|-

| S⁰ || 199.0 J/mol·K

|-

| [[Heat capacity|C_p]] || 123.6 J/mol·K

|-

| [[Density|Liquid density]]

| 0.64 ×10³ kg/m³

|}

{{clear}}

==See also==

*[[Cyclobutadiene]]

*[[Polybutadiene]]

*[[Hydroxyl-terminated polybutadiene]]

==References==

{{reflist|30em}}

==External links==

* [https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=458&toxid=81 1,3-Butadiene] – Agency for Toxic Substances and Disease Registry

* [https://www.cdc.gov/niosh/npg/npgd0067.html 1,3-Butadiene] – CDC - NIOSH Pocket Guide to Chemical Hazards

* [https://www.dcceew.gov.au/environment/protection/npi/substances/fact-sheets/13-butadiene-vinyl-ethylene National Pollutant Inventory – 1,3-Butadiene]

{{hydrocarbons}}

{{Authority control}}

{{DEFAULTSORT:Butadiene, 1, 3-}}

[[Category:Alkadienes]]

[[Category:Hazardous air pollutants]]

[[Category:Monomers]]

[[Category:IARC Group 1 carcinogens]]

[[Category:U.S. Synthetic Rubber Program]]

[[Category:Commodity chemicals]]

[[Category:Petrochemicals]]

[[Category:Conjugated dienes]]