2,4-Difluorobenzoic Acid appears across industrial and scientific circles as a chemical with a niche but growing demand. This material falls under the category of fluorinated aromatic carboxylic acids, important for its unique chemical structure and properties. With a molecular formula of C7H4F2O2 and a CAS number of 367-21-5, it presents itself as a crystalline solid under standard laboratory conditions. Structurally, this compound takes the familiar benzoic acid backbone and swaps out hydrogen for fluorine atoms at the 2 and 4 positions on the phenyl ring. Modern industrial chemistry values such molecular tweaks for the way they alter reactivity and physical properties.
In its purest form, 2,4-Difluorobenzoic Acid comes as a white to off-white crystalline solid. This physical state—sometimes available as flakes, powder, or pearls—makes it easy to handle in most lab setups. It holds a melting point around 133–137 °C, allowing some flexibility in synthesis and purification. Solubility levels set it apart from non-fluorinated analogs: water solubility stays low, but the powder dissolves in organic solvents like methanol, ethanol, and acetone much more readily. Compared with benzoic acid, density moves a bit higher, typically 1.4–1.5 g/cm3. These adjustments arise mainly due to the two electronegative fluorine atoms crowding one side of the ring, making for unusual polarity and mild electron withdrawal. Such traits give chemists a useful lever to pull when altering reactivity in larger molecule syntheses.
Looking in detail at the structure, the two fluorine atoms at positions 2 and 4 on the aromatic ring alter electronic distribution. The COOH group sits opposite, serving as both a functional group for derivatization and a core structural anchor. Each fluorine atom exerts a strong electron-withdrawing effect, changing acidity and affecting how the acid interacts with bases and catalysts. The full molecular formula, C7H4F2O2, describes a seven-carbon frame decorated with two fluorines and a single carboxyl group, making the molecule look deceptively simple. On paper, the structure may seem straightforward, but its reactivity stands out compared to less substituted benzoic acids.
From a materials management standpoint, purity levels for 2,4-Difluorobenzoic Acid run above 98% in most reputable supply channels. Impurities include residual solvent traces, water content, and sometimes isomeric difluorobenzoic acids. The global trade of this raw chemical usually tags it under HS Code 29163900, which groups together miscellaneous aromatic acids and derivatives. Qualified handlers check for melting point, purity (using HPLC or GC), moisture content, and sometimes heavy metal or halide residue. Vendors present it as a raw material in sizes ranging from laboratory grams up to multiple-kilo industrial drums, always with detailed certificates of analysis to assure traceability and compliance.
Through direct experience in synthesis labs and coating additive production, 2,4-Difluorobenzoic Acid shows clear utility. Its modified acidity and lipophilicity encourage its use in making pharmaceuticals, agricultural chemicals, specialty polymers, and even some liquid crystal intermediates. The dual fluorine substitution helps it resist biotransformation, so derivatives hang on in biological systems longer than non-fluorinated versions. For example, I’ve worked with it as a building block for drug discovery programs seeking increased metabolic stability and improved membrane permeability. In specialty materials, it adds thermal resistance and improved insulating characteristics, making it valuable in niche polymer blends or advanced coatings. Sourcing reliable supplies requires trusted vendors since small impurities or by-products can disrupt later reactions downstream.
On the bench, the material pours and weighs easily, behaving as a fine, almost slippery powder or sometimes broken up flakes. Density stays high enough that it doesn’t become airborne easily but still requires good technique to avoid loss during transfer. Solutions made from this compound stay stable for extended periods, especially in aprotic solvents. Safety protocols ask for gloves and eye protection at minimum, as the powder may cause irritation on skin or mucous membranes. Material safety data sheets classify it as a low-moderate hazard, mainly due to the irritant properties typical of aromatic acids. It burns with some difficulty, and the fluorinated exhaust may become hazardous in poorly ventilated spaces. Safe storage means cool, dry, and preferably sealed environments—moisture introduces clumping and may degrade purity over time.
Most fluorinated benzoic acids, including 2,4-Difluorobenzoic Acid, present moderate environmental persistence compared to simple organics. The two fluorine atoms form strong bonds and resist microbial breakdown, which can be a blessing or a curse depending on where the spent material winds up. I’ve seen issues arise from small spills or improper disposal—fluorinated acids contaminate groundwater more easily than non-fluorinated alternatives. Responsible users follow strict disposal and containment protocols, using proper neutralization and tracking any waste streams. Acute health effects rarely go beyond minor skin or eye irritation, but chronic exposure sometimes raises bioaccumulation concerns, especially as the compound persists in water and soil. Regulatory trends push for greener benches, so users face increasing scrutiny about downstream impacts and alternatives, prompting more research into biodegradable analogs or improved reclamation.
Minimizing risk means adopting efficient containment, monitoring storerooms for leaks, and using high-grade analytical methods to confirm identity and purity. Some researchers suggest shifting certain synthetic steps toward milder reagents and looking for ways to recycle spent acid after reactions, either through purification or chemical transformation. Where possible, closed systems limit exposure and mitigate loss, particularly in scale-up. Exploring green solvents and advanced filtration should take priority, moving toward more sustainable handling and less environmental trace. Teams benefit from routine safety drills and updated documentation, which pays off in both preventing incidents and satisfying external audits. Sourcing raw materials from reputable suppliers that adhere to documented manufacturing standards reduces worries about hidden contaminants or trace embodied toxicity. By weaving these practices into daily routines, labs and businesses maintain both a safer workplace and a cleaner ecological footprint.
