In the vast landscape of organic chemistry, understanding the properties and synthesis routes of key intermediates is fundamental for innovation. 4-Fluorophenylacetic acid, identified by CAS number 405-50-5, is one such compound that plays a pivotal role, especially in the pharmaceutical and fine chemical industries. Its unique structural features, including the presence of a fluorine atom, dictate its reactivity and applicability in complex synthetic processes.

Chemical Structure and Properties of 4-Fluorophenylacetic Acid

4-Fluorophenylacetic acid, also known as p-Fluorophenylacetic acid or 2-(4-fluorophenyl)acetic acid, is characterized by its molecular formula C8H7FO2 and a molecular weight of 154.14 g/mol. The molecule consists of a phenylacetic acid backbone where a fluorine atom is attached to the phenyl ring at the para (4-) position. This fluorine substitution significantly influences the compound's properties:

  • Acidity: The electron-withdrawing nature of fluorine can slightly increase the acidity of the carboxylic acid group compared to unsubstituted phenylacetic acid.
  • Reactivity: The carboxylic acid group is amenable to various reactions, such as esterification, amidation, and reduction. The aromatic ring can also undergo electrophilic aromatic substitution, though the fluorine atom and the acetic acid side chain will direct substitution.
  • Physical Appearance: It is typically observed as a white to off-white crystalline powder or solid.
  • Solubility: It exhibits moderate solubility in organic solvents and limited solubility in water.

These properties make it a versatile building block for further chemical transformations.

Synthesis Methods for 4-Fluorophenylacetic Acid

The production of 4-Fluorophenylacetic acid involves several synthetic strategies, often starting from readily available fluorinated aromatic compounds. While specific industrial processes are proprietary, common laboratory and industrial approaches include:

  1. From 4-Fluorobenzyl Halides: A common route involves the reaction of 4-fluorobenzyl halides (e.g., 4-fluorobenzyl chloride or bromide) with cyanide ions to form 4-fluorophenylacetonitrile. Subsequent hydrolysis of the nitrile group under acidic or basic conditions yields 4-Fluorophenylacetic acid.
  2. Via Grignard Reagents: Another method could involve forming a Grignard reagent from a 4-halofluorobenzene, followed by reaction with a suitable electrophile that can be converted to the acetic acid moiety.
  3. Biocatalysis: Research has also explored biotransformation methods, such as the conversion of 4-fluorophenylacetonitrile to 4-Fluorophenylacetic acid using specific microbial enzymes. This approach can offer milder reaction conditions and higher selectivity.

Regardless of the method, purification steps are crucial to obtain the high purity required for its applications. Common purification techniques include recrystallization and chromatography.

Where to Buy High-Quality 4-Fluorophenylacetic Acid

For researchers and manufacturers seeking to buy 4-Fluorophenylacetic acid, sourcing from reliable chemical suppliers is paramount. Manufacturers in China, such as Ningbo Inno Pharmchem Co., Ltd., are well-established providers of this intermediate, offering high purity and competitive pricing. When selecting a supplier, consider factors like:

  • Product Purity: Look for guaranteed assay levels (e.g., ≥98%).
  • Technical Data: Ensure availability of MSDS, CoA, and specifications.
  • Bulk Availability: Confirm that the supplier can meet your required quantities, from lab scale to industrial production.
  • Customer Service: Responsive communication and support are vital for a smooth procurement process.

Conclusion

4-Fluorophenylacetic acid (CAS 405-50-5) is a vital organic intermediate whose chemical properties and synthetic accessibility underpin its importance in advanced chemical synthesis. Its role in pharmaceutical development, in particular, highlights the value of this fluorinated compound. By understanding its synthesis and sourcing it from reputable manufacturers, businesses can ensure the quality and consistency needed for their critical applications.