Phenylacetylene
From Wikipedia, the free encyclopedia
| Phenylacetylene | |
|---|---|
Ethynylbenzene | |
| Identifiers | |
| CAS number | 536-74-3 |
| SMILES | C#Cc1ccccc1 |
| Properties | |
| Molecular formula | C8H6 |
| Molar mass | 102.133 g/mol |
| Density | 0.93 g/cm³ |
| Melting point | –45 °C |
| Boiling point | 142-144 °C |
| Acidity (pKa) | 28.8 |
| (what is this?) (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) | |
| Infobox references | |
Phenylacetylene is an alkyne hydrocarbon containing a phenyl group. It exists as a colorless, viscous liquid. In research, it is sometimes used as an analog for acetylene; being a liquid, it is easier to handle than acetylene gas.
Contents |
Preparation
In the laboratory, phenylacetylene can be prepared by elimination of hydrogen bromide from styrene dibromide using sodium amide in ammonia:[1]
It can also be prepared by the elimination of hydrogen bromide from bromostyrene using molten potassium hydroxide.[2]
Reactions
- Phenylacetylene can be reduced (hydrogenated) by hydrogen over Lindlar catalyst to give styrene.
- It undergoes a metal catalyzed trimerization to give 1,2,4- (97%) and 1,3,5-triphenylbenzene:[3]
- File:Alkyne trimerisation.gif
- It undergoes a hydration reaction, catalyzed by gold(III) or mercury(II), to give acetophenone.
See also
References
- ^ Kenneth N. Campbell and Barbara K. Campbell (1963), "Phenylacetylene", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv4p0763; Coll. Vol. 4: 763
- ^ John C. Hessler (1941), "Phenylacetylene", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv1p0438; Coll. Vol. 1: 438
- ^ Gerhard Hilt , Thomas Vogler, Wilfried Hess, Fabrizio Galbiati (2005). [Expression error: Missing operand for > "A simple cobalt catalyst system for the efficient and regioselective cyclotrimerisation of alkynes"]. Chemical Communications 2005 (11): 1474–1475. doi:.
