Phenylacetylene
[CAS# 536-74-3]

Identification

• Classification: Chemical reagent >> Organic reagent >> Alkyne
• Name: Phenylacetylene
• Synonyms: Ethynylbenzene
• Molecular Formula: C₈H₆
• Molecular Weight: 102.13
• CAS Registry Number: 536-74-3
• EC Number: 208-645-1
• SMILES: C#CC1=CC=CC=C1

Properties

• Density: 0.928
• Melting point: -44.8 ºC
• Boiling point: 142-144 ºC
• Refractive index: 1.547-1.55
• Flash point: 31 ºC
• Water solubility: INSOLUBLE

Safety Data

• Hazard Symbols: GHS02;GHS07;GHS08 Danger
• Hazard Statements: H226-H304-H315-H319-H335
• Precautionary Statements: P210-P233-P240-P241-P242-P243-P261-P264-P264+P265-P271-P280-P301+P316-P302+P352-P303+P361+P353-P304+P340-P305+P351+P338-P319-P321-P331-P332+P317-P337+P317-P362+P364-P370+P378-P403+P233-P403+P235-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Flammable liquids	Flam. Liq.	3	H226
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Aspiration hazard	Asp. Tox.	1	H304
Specific target organ toxicity - single exposure	STOT SE	3	H335
Carcinogenicity	Carc.	2	H351
Skin corrosion	Skin Corr.	1	H314
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	3	H331
Serious eye damage	Eye Dam.	1	H318
Eye irritation	Eye Irrit.	2A	H319
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412

• Transport Information: UN 3295

Discovory and Applicatios

Phenylacetylene is a versatile chemical compound characterized by its distinct phenyl and acetylene groups, providing it with a unique set of chemical properties. This compound, often represented by the formula C8H6, consists of a phenyl group attached to an acetylene group, making it an important building block in organic chemistry.

The discovery of phenylacetylene dates back to the early 20th century, during which it was identified as a key intermediate in the synthesis of various organic compounds. Initially synthesized through the dehydrohalogenation of phenylhalogen derivatives, phenylacetylene has since been recognized for its utility in multiple chemical applications.

In organic synthesis, phenylacetylene serves as a fundamental intermediate for the production of a range of complex molecules. Its triple bond is highly reactive, making it suitable for a variety of addition reactions. For instance, phenylacetylene is employed in the synthesis of aryl-substituted alkynes through reactions with other electrophiles. This reactivity also makes it useful in the preparation of functionalized aromatic compounds, which are important in pharmaceutical and materials chemistry.

One of the significant applications of phenylacetylene is in the field of materials science. The compound is used to synthesize polyphenylacetylene, a polymer with notable electronic and optical properties. Polyphenylacetylene has been explored for use in organic light-emitting diodes (OLEDs), organic photovoltaics, and other electronic devices. Its unique electronic structure allows it to contribute to the development of advanced materials with specific conductivity and emission characteristics.

In medicinal chemistry, phenylacetylene and its derivatives are utilized to design and synthesize bioactive compounds. The compound's ability to undergo various chemical transformations makes it a valuable tool for developing new pharmaceuticals. For instance, phenylacetylene has been incorporated into the synthesis of potential anti-cancer agents and other therapeutic molecules due to its reactivity and ability to form diverse chemical structures.

Moreover, phenylacetylene is employed in the field of chemical biology as a reactive probe. It can be used to label and study specific biomolecules or to probe chemical interactions within biological systems. This application is particularly valuable in understanding biochemical processes and in the development of targeted therapies.

Overall, phenylacetylene is a crucial compound in organic chemistry with diverse applications in materials science, medicinal chemistry, and chemical biology. Its unique chemical properties and reactivity make it an essential tool for synthesizing complex molecules and developing advanced materials and therapeutic agents.

References

2024. Copper-catalysed synthesis of chiral alkynyl cyclopropanes using enantioconvergent radical cross-coupling of cyclopropyl halides with terminal alkynes. Nature Synthesis, 3(11).
DOI: 10.1038/s44160-024-00654-x

2007. An examination of structural characteristics of phenylacetylene by vibronic and rovibronic simulations of ab initio data. Physical Chemistry Chemical Physics, 9(38).
DOI: 10.1039/b705194h

2003. Catalytic Alkynylation of Ketones and Aldehydes Using Quaternary Ammonium Hydroxide Base. The Journal of Organic Chemistry, 68(7).
DOI: 10.1021/jo026592g