Nomenclature
CAS number: 463-51-4
Ethenone; carbomethene.
C
2H
2O; mol wt 42.04.
C 57.14%, H 4.80%, O 38.06%.
CH
2=C=O.
Description and references
Prepd by the thermal decompn of acetone, diketene
or acetic anhydride: Hurd, Org. Synth. coll. vol. I, 330 (2nd ed., 1941); S. Andreades, H. D.
Carlson, ibid. coll. vol. V, 679 (1973). Structure
of ketene dimer as 3-buteno-β-lactone: Blomquist, Baldwin, J. Am. Chem. Soc. 70, 29 (1948);
Hurd, Blanchard, ibid. 72, 1461 (1950); Katz,
Lipscomb, J. Org. Chem. 17, 515 (1953). Toxicology: J. F. Treon et al., J. Ind. Hyg. Toxicol. 31, 209
(1949). Review on the prepn of stable ketenes: R. S.
Ward in The Chemistry of Ketenes, Allenes
and Related Compounds Part 1,, S. Patai, Ed.
(Wiley, New York, 1980) pp 223-277; on synthetic uses of ketenes:
W. T. Brady, ibid. pp 279-308.
Properties
Gas. Penetrating odor. mp 150°. bp 56°. Electron diffraction pictures: Beach, Stevenson, J. Chem. Phys. 6, 75 (1938).
Fairly sol in acetone. All operations with ketene should be carried
out in an efficient hood (Andreades, Carlson).Caution
Potential symptoms of overexposure
are irritation of skin, eyes, nose, throat and respiratory system;
pulmonary edema. See NIOSH Pocket
Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p
184.Use
For the conversion of higher acids into their anhydrides;
for acetylation in the manuf of cellulose acetate and aspirin.