Ethenone

Ethenone
Names
	Systematic IUPAC name Ethenone
	Other names Ketene
Identifiers
CAS Number	463-51-4 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:48003 ;
ChemSpider	9643 ;
ECHA InfoCard	100.006.671
CompTox Dashboard (EPA)	DTXSID1052113 ;
	InChI InChI=1S/C2H2O/c1-2-3/h1H2 Key: CCGKOQOJPYTBIH-UHFFFAOYSA-N ; InChI=1/C2H2O/c1-2-3/h1H2 Key: CCGKOQOJPYTBIH-UHFFFAOYAO; InChI=1/C2H2O/c1-2-3/h1H2 Key: CCGKOQOJPYTBIH-UHFFFAOYAO;
	SMILES O=C=C;
Properties
Chemical formula	C2H2O
Molar mass	42.04 g/mol
Appearance	Colourless gas
Melting point	-150.5 °C (-239 °F)
Boiling point	-56.1 °C (-69 °F)
Solubility	acetone; ethanol; ethyl ether; aromatic solvents; halocarbons
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Ethenone is the formal name for ketene, an organic compound with formula C₂H₂O or H₂C=C=O. It is the simplest member of the ketene class. It is a tautomer of ethynol.

Properties

Ethenone is a colourless gas at STP and has a sharp irritating odour. It is soluble in acetone, ethanol, ethyl ether, aromatic solvents and halocarbons.

Preparation

Ethenone can be prepared in the laboratory by pyrolysis of acetone vapor.^[1]

Reactions

Ethenone is very reactive, tending to react with nucleophiles to form an acetyl group. For example, it reacts with acetic acid to form acetic anhydride. It also reacts with water to form acetic acid^[2].

Ethenone will also react with itself via 2+2 photocycloaddition to form cyclic dimers known as diketenes. For this reason, it should not be stored for long periods.^{[citation needed]}

Hazards

Exposure to concentrated levels causes humans to experience irritation of body parts such as the eye, nose, throat and lungs. Extended toxicity testing on mice, rats, guinea pigs and rabbits showed that ten minute exposures to concentrations of freshly generated ethenone as low as 0.2 mg/liter (116 ppm) may produce a high percentage of deaths in small animals. These findings put ethenone in the same order of toxicity as phosgene (0.2-20 mg/liter) and hydrogen cyanide (0.2-0.5 mg/liter). Death is from pulmonary edema and is entirely similar to, but much more rapid than is the case with phosgene poisoning.^[3]

References

^ C. D. Hurd (1941). "Ketene". Organic Syntheses; Collected Volumes, vol. 1, p. 330..
^ ChemSpider http://www.chemspider.com/Chemical-Structure.9643.html
^ H. A. Wooster, C. C. Lushbaugh, C. E. Redeman (1946). "The Inhalation Toxicity of Ketene and of Ketene Dimer". J. Am. Chem. Soc. 68 (12): 2743. doi:10.1021/ja01216a526.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[1] C. D. Hurd (1941). "Ketene". Organic Syntheses; Collected Volumes, vol. 1, p. 330..

[2] ChemSpider http://www.chemspider.com/Chemical-Structure.9643.html

[3] H. A. Wooster, C. C. Lushbaugh, C. E. Redeman (1946). "The Inhalation Toxicity of Ketene and of Ketene Dimer". J. Am. Chem. Soc. 68 (12): 2743. doi:10.1021/ja01216a526.{{cite journal}}: CS1 maint: multiple names: authors list (link)

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