Diacetylene
Structural formula
Space-filling model
Names
Preferred IUPAC name
Buta-1,3-diyne
Other names
1,3-Butadiyne
Biacetylene
Butadiyne
Identifiers
3D model (JSmol)
1236317
ChEBI
ChemSpider
ECHA InfoCard 100.006.641 Edit this at Wikidata
EC Number
  • 207-303-9
UNII
  • InChI=1S/C4H2/c1-3-4-2/h1-2H checkY
    Key: LLCSWKVOHICRDD-UHFFFAOYSA-N checkY
  • InChI=1/C4H2/c1-3-4-2/h1-2H
    Key: LLCSWKVOHICRDD-UHFFFAOYAU
  • C#CC#C
Properties
C4H2
Molar mass 50.060 g·mol−1
Appearance Gas
Boiling point 10 °C (50 °F; 283 K)
Hazards
Main hazards Highly flammable; Peroxide forming
Safety data sheet External MSDS
GHS pictograms GHS01: ExplosiveGHS02: Flammable
GHS Signal word Danger
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Diacetylene (also known as butadiyne) is the organic compound with the formula C4H2. It is the simplest compound containing two triple bonds. It is first in the series of polyynes, which are of theoretical but not of practical interest.

Occurrence

Diacetylene has been identified in the atmosphere of Titan and in the protoplanetary nebula CRL 618 by its characteristic vibrational spectrum. It is proposed to arise by a reaction between acetylene and the ethynyl radical (C2H), which is produced when acetylene undergoes photolysis. This radical can in turn attack the triple bond in acetylene and react efficiently even at low temperatures. Diacetylene has also been detected on the Moon.

Preparation

This compound may be made by the dehydrohalogenation of 1,4-dichloro-2-butyne by potassium hydroxide (in alcoholic medium) at ~70°C:[1]

ClCH2C≡CCH2Cl + 2 KOH → HC≡C−C≡CH + 2 KCl + 2 H2O

The bis(trimethylsilyl)-protected derivative may be prepared by the Hay coupling of (trimethylsilyl)acetylene:[2]

2 Me3Si−C≡CH → Me3Si−C≡C−C≡C−SiMe3

See also

References

  1. ^ Verkruijsse, H. D.; Brandsma, L. (1991). "A Detailed Procedure for the Preparation of Butadiyne". Synthetic Communications. 21 (5): 657. doi:10.1080/00397919108020833.
  2. ^ Graham E. Jones, David A. Kendrick, and Andrew B. Holmes (1993). "1,4-Bis(trimethylsilyl)buta-1,3-diyne". Organic Syntheses. doi:10.15227/orgsyn.065.0052.CS1 maint: multiple names: authors list (link); Collective Volume, 8, p. 63

Further reading

  • Maretina, Irina A; Trofimov, Boris A (2000). "Diacetylene: a candidate for industrially important reactions". Russian Chemical Reviews. 69 (7): 591. doi:10.1070/RC2000v069n07ABEH000564.