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2,3-Butanediol

2,3-Butanediol
2,3-butanediol
Names
IUPAC name
Butane-2,3-diol
Other names
2,3-Butylene glycol
Dimethylene glycol
2,3-Dihydroxybutane
Butan-2,3-diol
Identifiers
3D model (Jmol)
ChEBI
ChemSpider
ECHA InfoCard 100.007.431
EC Number 208-173-6
PubChem CID
Properties
C4H10O2
Molar mass 90.121 g/mol
Appearance nearly colorless solid or liquid
Odor odorless
Density 0.987 g/mL
Melting point 19 °C (66 °F; 292 K)
Boiling point 177 °C (351 °F; 450 K)
miscible
Solubility soluble in alcohol, ketones, ether
log P -0.92
Vapor pressure 0.23 hPa (20 °C)
Acidity (pKa) 14.9
1.4366
Thermochemistry
213.0 J/K mol
-544.8 kJ/mol
Hazards
Flammable (F)
R-phrases R11
S-phrases (S2) S7 S16
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 85 °C (185 °F; 358 K)
402 °C (756 °F; 675 K)
Lethal dose or concentration (LD, LC):
LD50 (median dose)
5462 mg/kg (rat, oral)
Related compounds
Related butanediols
1,4-Butanediol
1,3-Butanediol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YesYN ?)
Infobox references

2,3-Butanediol is a organic compound with the formula is (CH3)2(CHOH)2. 2,3-Butanediol has three stereoisomers, all of which are colorless, viscous liquids. Butanediols have applications as precursors to various plastics and pesticides.

Of the three stereoisomers, two are enantiomers (levo- and dextro-2,3-butanediol) and one is a meso compound. The enantiomeric pair have (2R, 3R) and (2S, 3S) configurations at carbons 2 and 3, while the meso compound has configuration (2R, 3S) or, equivalently, (2S, 3R).

2,3-Butanediol is prepared by hydrolysis of 2,3-butene oxide:

The isomer distribution depends on the stereochemistry of the epoxide.

The meso isomer is used to combine with naphthalene-1,5-diisocyanate. The resulting polyurethane is called "Vulkollan".

The (2R,3R)-stereoisomer of 2,3-butanediol is produced by a variety of microorganisms in a process known as butanediol fermentation. It is found naturally in cocoa butter, in the roots of Ruta graveolens, sweet corn, and in rotten mussels. It is used in the resolution of carbonyl compounds in gas chromatography.

During World War II research was done towards producing 2,3-butanediol by fermentation in order to produce 1,3-butadiene, the monomer of the polybutadiene used in a leading type of synthetic rubber.

7. C. De Mas, N. B. Jansen, G. T. Tsao (1988). "Production of optically active 2,3-butanediol by Bacillus polymyxa." Biotechnol. Bioeng. 31(4): 366-77.


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