3-Pentanone

3-Pentanone

Skeletal formula of 3-pentanone
Ball-and-stick model of 3-pentanone
Names
IUPAC name Pentan-3-one
Other names diethyl ketone, diethylketone, 3-pentanone, dimethyl acetone, propione, DEK, metacetone, methacetone, ethyl ketone
Identifiers
CAS Number	96-22-0 Y
ChEBI	CHEBI:87755 Y
ChEMBL	ChEMBL45315 Y
ChemSpider	7016 Y
Jmol 3D model	Interactive image
UNII	9SLZ98M9NK Y
InChI InChI=1S/C5H10O/c1-3-5(6)4-2/h3-4H2,1-2H3 Y Key: FDPIMTJIUBPUKL-UHFFFAOYSA-N Y InChI=1/C5H10O/c1-3-5(6)4-2/h3-4H2,1-2H3 Key: FDPIMTJIUBPUKL-UHFFFAOYAJ
SMILES O=C(CC)CC
Properties
Chemical formula	C5H10O
Molar mass	86.13 g·mol−1
Appearance	Colorless liquid
Odor	Acetone-like
Density	0.815 g/cm3
Melting point	−39 °C (−38 °F; 234 K)
Boiling point	100 to 102 °C (212 to 216 °F; 373 to 375 K)
Solubility in other solvents	water: 50 g/L (20 °C)
Vapor pressure	35 mmHg (25°C)
Vapor pressure	{{{value}}}
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

3-Pentanone (also known as diethyl ketone) is a simple, symmetrical dialkyl ketone. It is a colorless liquid ketone with an odor like that of acetone. It is soluble in about 25 parts water, but miscible with organic solvents. It is mainly used as a solvent in paint and a precursor to vitamin E. It is easily soluble in diethyl ether and partially soluble in acetone, methanol, and water. Two related and more important ketones are 2-pentanone and methyl isopropyl ketone.

Syntheses

3-Pentanone is produced industrially from propionic acid using metal oxide catalysts:

2 CH₃CH₂CO₂H → (CH₃CH₂)₂CO + CO₂ + H₂O

It can also be prepared by ketonic decarboxylation of propanoic acid over a manganese(II) oxide catalyst in a tube furnace or from ethylene, CO, and H₂.

In the case of dicobalt octacarbonyl or Co₂(CO)₈ as a catalyst, 3-pentanone can arise from ethylene and CO, in the absence of hydrogen. A proposed intermediate is the ethylene-propionyl species [CH₃C(O)Co(CO)₃(ethylene)] which undergoes a migratory insertion to form [CH₃COCH₂CH₂Co(CO)₃]. The required hydrogen arises from the water shift reaction. For details, see

Conversion of ethylene to diethyl ketone using a cobalt carbonyl, while the reaction used a cobalt carbonyl diphosphine complex for clarity the reaction has been drawn out, assuming that a cobalt carbonyl is responsible for the reaction

If the water shift reaction is not operative, the reaction affords a polymer containing alternating carbon monoxide and ethylene units. Such aliphatic polyketones are more conventionally prepared using palladium catalysts.

Safety

The TLV value for 3-pentanone is 200 ppm (705 mg/m³). 3-pentanone can be hazardous if it comes in contact with the skin or eyes, and can cause irritation of the skin and redness, watering, and itching of the eyes. This chemical can also cause nervous system or organ damage if ingested. Although considered stable, 3-pentanone is extremely flammable if exposed to flame, sparks, or another source of heat. For safety, it should be stored in a flammable materials cabinet away from heat or sources of ignition, preferably in a cool, well-ventilated area.