Butanone

Butanone

Names
Preferred IUPAC name Butan-2-one
Other names Ethyl methyl ketone Methyl ethyl ketone (not recommended) MEK 2-Butanone Methylpropanone Ethylmethylketone Methylacetone
Identifiers
CAS Number	78-93-3 Y
3D model (Jmol)	Interactive image Interactive image
Beilstein Reference	741880
ChEBI	CHEBI:28398 Y
ChEMBL	ChEMBL15849 Y
ChemSpider	6321 Y
ECHA InfoCard	100.001.054
Gmelin Reference	25656
KEGG	C02845 Y
PubChem	6569
RTECS number	EL6475000
UNII	6PT9KLV9IO Y
InChI InChI=1S/C4H8O/c1-3-4(2)5/h3H2,1-2H3 Y Key: ZWEHNKRNPOVVGH-UHFFFAOYSA-N Y InChI=1/C4H8O/c1-3-4(2)5/h3H2,1-2H3 Key: ZWEHNKRNPOVVGH-UHFFFAOYAW
SMILES O=C(C)CC CCC(=O)C
Properties
Chemical formula	C4H8O
Molar mass	72.11 g·mol−1
Appearance	Colorless liquid
Odor	mint or acetone-like
Density	0.8050 g/mL
Melting point	−86 °C (−123 °F; 187 K)
Boiling point	79.64 °C (175.35 °F; 352.79 K)
Solubility in water	27.5 g/100 mL
Vapor pressure	78 mmHg (20°C)
Acidity (pKa)	14.7
Magnetic susceptibility (χ)	-45.58·10−6 cm3/mol
Refractive index (nD)	1.37880
Viscosity	0.43 cP
Structure
Dipole moment	2.76 D
Hazards
Safety data sheet	See: data page
EU classification (DSD)	Flammable (F) Irritant (Xi)
R-phrases	R11 R36 R66 R67
S-phrases	(S2) S9 S16
NFPA 704	3 1 0
Flash point	−9 °C (16 °F; 264 K)
Autoignition temperature	505 °C (941 °F; 778 K)
Explosive limits	1.4%-11.4%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	2737 mg/kg (oral, rat) 4050 mg/kg (oral, mouse)
LC50 (median concentration)	12667 ppm (mammal) 13333 ppm (mouse, 2 hr) 7833 ppm (rat, 8 hr)
US health exposure limits (NIOSH):
PEL (Permissible)	TWA 200 ppm (590 mg/m3)
REL (Recommended)	TWA 200 ppm (590 mg/m3) ST 300 ppm (885 mg/m3)
IDLH (Immediate danger)	3000 ppm
Related compounds
Related Ketones	Acetone; 3-pentanone; 3-Methylbutanone
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Butanone, also known as methyl ethyl ketone (MEK), is an organic compound with the formula CH₃C(O)CH₂CH₃. This colorless liquid ketone has a sharp, sweet odor reminiscent of butterscotch and acetone. It is produced industrially on a large scale, and also occurs in trace amounts in nature. It is soluble in water and is commonly used as an industrial solvent.

Butanone may be produced by oxidation of 2-butanol. The dehydrogenation of 2-butanol using a catalyst is catalyzed by copper, zinc, or bronze:

This is used to produce approximately 700 million kilograms yearly. Other syntheses that have been examined but not implemented include Wacker oxidation of 2-butene and oxidation of isobutylbenzene, which is analogous to the industrial production of acetone.

Both liquid-phase oxidation of heavy naphtha and the Fischer-Tropsch reaction produce mixed oxygenate streams, from which 2-butanone is extracted by fractionation.

Butanone is biosynthesized by some trees and found in some fruits and vegetables in small amounts. It is released to the air from car and truck exhausts.

Butanone is an effective and common solvent and is used in processes involving gums, resins, cellulose acetate and nitrocellulose coatings and in vinyl films. For this reason it finds use in the manufacture of plastics, textiles, in the production of paraffin wax, and in household products such as lacquer, varnishes, paint remover, a denaturing agent for denatured alcohol, glues, and as a cleaning agent. It has similar solvent properties to acetone but boils at a higher temperature and has a significantly slower evaporation rate. Butanone is also used in dry erase markers as the solvent of the erasable dye.