:1,2-Butanediol
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 477203212
| Name = 1,2-Butanediol
| ImageFile = 1,2-Butanediol.png
| ImageName = Molecular formula of 1,2-Butanediol
| ImageFile1 = 1,2-Butanediol-3D-balls-2.png
| ImageSize1 =
| ImageAlt1 = Butanediol molecule
| PIN = Butane-1,2-diol
| OtherNames = 1,2-Dihydroxybutane
α-Butylene glycol
|Section1={{Chembox Identifiers
| InChI = 1/C4H10O2/c1-2-4(6)3-5/h4-6H,2-3H2,1H3
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C4H10O2/c1-2-4(6)3-5/h4-6H,2-3H2,1H3
| InChIKey = BMRWNKZVCUKKSR-UHFFFAOYAV
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = BMRWNKZVCUKKSR-UHFFFAOYSA-N
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = RUN0H01QEU
| SMILES = OCC(O)CC
| SMILES1 = CCC(CO)O
| CASNo = 584-03-2
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo1_Ref = {{cascite|changed|??}}
| CASNo1 = 40348-66-1
| CASNo1_Comment= (R)
| CASNo2_Ref = {{cascite|changed|??}}
| CASNo2 = 73522-17-5
| CASNo2_Comment= (S)
| EC_number = 209-527-2
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 52682
| ChemSpiderID = 10948
| RTECS = EK0380000
| PubChem = 11429
}}
|Section2={{Chembox Properties
| Properties_ref = {{RubberBible62nd|page=C-190}}.
| Formula = C{{sub|4}}H{{sub|10}}O{{sub|2}}
| MolarMass = 90.121 g/mol
| Density = 1.0023 g/cm{{sup|3}} (20 °C)
| MeltingPtC = −50
| MeltingPt_ref = The value of −50 °C for the melting point is taken from Ullmann's Encyclopedia of Industrial Chemistry and used by the Hazardous Substances Data Bank and the OECD Screening Information Dataset. Other reported values of the melting point range from −114 °C to −30 °C.
| BoilingPtC = 195 to 196.9
| BoilingPt_notes = (96.5 °C at 10 mmHg)
| Solubility = miscible
| SolubleOther = soluble in ethanol, acetone; sparingly soluble in esters and ethers; insoluble in hydrocarbons
| RefractIndex = 1.4378 (20 °C)
| Viscosity = 7.3 mPa·s (20 °C)
}}
|Section3={{Chembox Thermochemistry
| DeltaHf = −532.8 kJ/mol {{citation | last1 = Moureu | first1 = H. | last2 = Dode | first2 = M. | title = Chaleurs de formation de l'oxyde d'ethylene, de l'ethanediol et de quelques homologues | journal = Bull. Soc. Chim. Fr. | year = 1937 | volume = 4 | pages = 637–47}}.
| DeltaHc = −2479 kJ/mol
}}
|Section7={{Chembox Hazards
| Hazards_ref = {{ICSC-ref|03|95|name=1,2-Butanediol|date=March 1996}}.
| ExternalSDS = [http://www.inchem.org/documents/icsc/icsc/eics0395.htm ICSC 0395]
| FlashPtC = 90
}}
|Section8={{Chembox Related
| OtherFunction = 1,3-Butanediol
1,4-Butanediol
2,3-Butanediol
| OtherFunction_label = butanediols
| OtherCompounds = Ethylene glycol
Propylene glycol
2-Hydroxybutyraldehyde
2-Hydroxybutyric acid
α-Ketobutyric acid
}}
}}
1,2-Butanediol is the organic compound with the formula HOCH{{sub|2}}(HO)CHCH{{sub|2}}CH{{sub|3}}. It is classified as a vic-diol (glycol). It is chiral, although typically it is encountered as the racemic mixture. It is a colorless liquid.
Preparation
This diol was first described by Charles-Adolphe Wurtz in 1859.{{citation|last=Wurtz|first=A.|title=Mémoire sur les glycols ou alcools diatomique|url=https://gallica.bnf.fr/ark:/12148/bpt6k6567326h/f403.item|journal=Ann. Chim. Phys.|volume=55|pages=400|year=1859|trans-title=Dissertation on glycols, or diatomic alcohols|authorlink=Charles-Adolphe Wurtz}}.
It is produced industrially by hydration of 1,2-epoxybutane.{{Ullmann | title= Butanediols, Butenediol, and Butynediol|Heinz Gräfje et al.|year=2005|doi=10.1002/14356007.a04_455}}{{SIDS-ref| id=584032 |name=1,2-Butanediol|date=February 1995}}.
This process requires a ten- to twenty-fold excess of water to suppress the formation of polyethers. Depending on the amount of excess water, the selectivity varies from 70 to 92%.{{Citation|last1=Gräfje|first1=Heinz|title=Butanediols, Butenediol, and Butynediol|date=2019-07-23|url=https://onlinelibrary.wiley.com/doi/10.1002/14356007.a04_455.pub2|encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry|pages=1–12|place=Weinheim, Germany|publisher=Wiley-VCH Verlag GmbH & Co. KGaA|language=en|doi=10.1002/14356007.a04_455.pub2|isbn=978-3-527-30673-2|access-date=2022-02-18|last2=Körnig|first2=Wolfgang|last3=Weitz|first3=Hans-Martin|last4=Reiß|first4=Wolfgang|last5=Steffan|first5=Guido|last6=Diehl|first6=Herbert|last7=Bosche|first7=Horst|last8=Schneider|first8=Kurt|last9=Kieczka|first9=Heinz|url-access=subscription}} Sulfuric acid or strongly acidic ion exchange resins may be used as catalysts, which allows the reaction to occur under 160 °C and at slightly above atmospheric pressure.
1,2-Butanediol is a byproduct of the production of 1,4-butanediol from butadiene.{{cite patent | inventor1-last = Hasegawa | inventor1-first = Ryuichi | inventor2-last = Hayashi | inventor2-first = Kohji | assign = Mitsubishi Monsanto Chemical Company | title = Polyester containing impure 1,2-butanediol | country= US | number = 4596886 | pubdate = 1986-06-24}}. It is also a byproduct of the catalytic hydrocracking of starches and sugars such as sorbitol to ethylene glycol and propylene glycol.{{cite patent | inventor-last = Berg | inventor-first = Lloyd | title = Recovery of ethylene glycol from butanediol isomers by azeotropic distillation | country= US | number = 4966658 | pubdate = 1990-10-30}}. {{cite patent | inventor-last = Berg | inventor-first = Lloyd | title = Separation of propylene glycol from 1,2-butanediol by azeotropic distillation | country = US | number = 5423955 | pubdate = 1995-06-13}}.
It can also be obtained from the dihydroxylation of but-1-ene by OsO4.
Applications
It has been patented for the production of polyester resins and plasticizers. It is a potential feedstock for the industrial production of α-ketobutyric acid, a precursor to some amino acids.{{cite patent | inventor1-last = Imanari | inventor1-first = Makoto | inventor2-last = Iwane | inventor2-first = Hiroshi | inventor3-last = Suzuki | inventor3-first = Masashi | inventor4-last = Suzuki | inventor4-first = Naoki | assign = Mitsubishi Petrochemical Co., Ltd. | title = Process for preparing α-ketobutyric acid | country = US | number = 5155263 | pubdate = 1992-10-13}}.
Safety
The LD50 (rats, oral) is 16g/kg.
Notes
{{reflist|group="note"}}
References
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External links
- {{ICSC|03|95}}
- {{SIDS| id=584032 |name=1,2-Butanediol|date=February 1995}}
{{DEFAULTSORT:Butanediol, 1, 2-}}