From Wikipedia, the free encyclopedia
Jump to: navigation, search
Structural formula
Ball-and-stick model
CAS number 503-17-3 YesY
PubChem 10419
ChemSpider 9990 YesY
Jmol-3D images Image 1
Molecular formula C4H6
Molar mass 54.0904 g/mol
Density 0.691 g/mL
Melting point −32 °C (−26 °F; 241 K)
Boiling point 27 °C (81 °F; 300 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

2-Butyne (Dimethylacetylene, crotonylene or but-2-yne) is an alkyne with chemical formula CH3C≡CCH3. Produced artificially, it is a colorless, volatile, pungent liquid at standard temperature and pressure.


2-Butyne can be synthesized by the rearrangement of ethylacetylene in a solution of ethanolic potassium hydroxide.[3]


2-Butyne, along with propyne, is used to synthesize alkylated hydroquinones in the total synthesis of Vitamin E.[4]

See also[edit]


  1. ^ 2-Butyne at Sigma-Aldrich
  2. ^ NIST Chemistry WebBook page for 2-butyne
  3. ^ Victor von Richter and Hans Meerwein (1916). Organic Chemistry: Chemistry of the aliphatic series Vol. I: Smith's 3rd American Ed.. Philadelphia: P. Blakiston's Sons & Co. p. 89. 
  4. ^ Reppe, Walter; Kutepow, N; and Magin, A (1969). "Cyclization of Acetylenic Compounds". Angewandte Chemie International Edition in English 8 (10): 727–733. doi:10.1002/anie.196907271. Retrieved 26 December 2013.