In the realm of specialty chemicals, understanding the precise properties and potential applications of a compound is fundamental for its effective utilization. 3-Ethynylthiophene (CAS: 67237-53-0) is one such compound that garners significant attention from researchers and industrial chemists alike. This article delves into the key characteristics of 3-Ethynylthiophene and its diverse applications, highlighting its importance as a versatile intermediate.

Physical and Chemical Characteristics

3-Ethynylthiophene, with the molecular formula C6H4S and a molecular weight of 108.16 g/mol, presents itself as a liquid. Its appearance is typically described as colorless to yellow to orange, indicating slight variations that can occur during manufacturing or storage. The density is approximately 1.098 g/mL at 25°C, and its boiling point is around 152-153°C at ambient pressure, though it can boil at lower temperatures under reduced pressure (e.g., 50 °C/15 mmHg). A flash point of 46°C suggests moderate flammability.

Chemically, the defining feature of 3-Ethynylthiophene is the presence of both a thiophene ring and an ethynyl (acetylene) group. The thiophene ring contributes aromaticity and specific electronic properties, while the ethynyl group is highly reactive. This functional group readily participates in various chemical reactions, including:

• Click Chemistry: The terminal alkyne is an excellent partner for azide-alkyne cycloaddition reactions, a cornerstone of click chemistry, allowing for efficient and specific conjugation.
• Coupling Reactions: It can undergo various metal-catalyzed coupling reactions, such as Sonogashira coupling, to form new carbon-carbon bonds, crucial for extending molecular structures.
• Polymerization: The ethynyl group can be involved in polymerization processes, leading to conjugated polymers with interesting electronic and optical properties.

A minimum purity of 97% is commonly offered for this compound, which is essential for achieving reliable results in downstream applications.

Primary Applications

The unique combination of properties makes 3-Ethynylthiophene a valuable intermediate in several key areas:

• Synthesis Materials Intermediates: It serves as a foundational building block for creating more complex organic molecules. This includes intermediates for specialty chemicals, advanced polymers, and functional materials. Manufacturers often use it to produce high-value derivatives.
• Pharmaceutical Raw Intermediates: In the pharmaceutical industry, 3-Ethynylthiophene is utilized in the synthesis of drug candidates and active pharmaceutical ingredients (APIs). The thiophene scaffold is a common feature in many pharmaceuticals, and the ethynyl group offers a versatile handle for further modification.
• Materials Science: Its electronic properties make it relevant for research in organic electronics, such as organic semiconductors for OLEDs and solar cells. It can also be incorporated into novel materials with specific conductive or optical characteristics.

Sourcing and Availability

For those looking to buy 3-ethynylthiophene, it is important to consider its availability from reliable chemical suppliers and manufacturers. Companies in China often provide this compound with competitive 3-ethynylthiophene price options and assurances of high purity. When sourcing, always check for detailed product specifications and a Certificate of Analysis. Inquiring about free samples can also be a practical way to evaluate the quality from a potential manufacturer.

Conclusion

3-Ethynylthiophene is a compound of significant interest due to its versatile reactivity and applicability across synthesis, pharmaceuticals, and materials science. Understanding its physical and chemical properties, along with its key applications, is the first step towards leveraging its potential. For procurement professionals, identifying dependable suppliers offering high-purity 3-Ethynylthiophene is crucial for project success.