Propiolic acid

Propiolic acid
Names
IUPAC name
2-Propynoic acid
Other names
Acetylene carboxylic acid, Propargylic acid, 'acetylene mono-carboxylic acid
Identifiers
471-25-0 Yes
ChEBI CHEBI:33199 
ChEMBL ChEMBL1213530 
ChemSpider 9706 
EC number 207-437-8
Jmol-3D images Image
KEGG C00804 
MeSH C011537
PubChem 10110
Properties
C3H2O2
Molar mass 70.05 g/mol
Density 1.1325 g/cm3
Melting point 9 °C (48 °F; 282 K)
Boiling point 144 °C (291 °F; 417 K) (decomposes)
Hazards
MSDS External MSDS
EU classification T+
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
  verify (what is: Yes/?)
Infobox references

Propiolic acid is an unsaturated carboxylic acid. It is a colourless liquid that crystallises to give silky crystals. Near its boiling point, it decomposes. It is soluble in water and possesses an odor like that of acetic acid.[1]

Preparation

It is prepared commercially by oxidizing propargyl alcohol at a lead electrode.[2] It can also be prepared by decarboxylation of acetylenedicarboxylic acid.

Reactions and applications

Exposure to sunlight converts it into trimesic acid (benzene-1,3,5-tricarboxylic acid). It undergoes bromination to give dibromoacrylic acid. With hydrogen chloride it forms chloroacrylic acid. Its ethyl ester condenses with hydrazine to form pyrazolone.

It forms a characteristic explosive solid upon treatment to its aqueous solution with ammoniacal silver nitrate. An amorphous explosive precipitate forms with ammoniacal cuprous chloride.

References

  1. ed, Susan Budavari, (1990). The Merck index an encyclopedia of chemicals, drugs, and biologicals (11. ed., 2. print. ed.). Rahway, NJ: Merck. pp. 7833,1911. ISBN 9780911910285.
  2. Wilhelm Riemenschneider "Carboxylic Acids, Aliphatic" Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a05_235.