3,4-Difluoro-2-methoxyphenylacetic acid belongs to the compound class of phenylacetic acids, often recognized by its distinctive molecular structure. At its core, it carries two fluorine atoms placed on a benzene ring, at the third and fourth positions, linking through a methoxy group at the second position and a phenylacetic acid group. The molecular formula stands as C9H8F2O3, reflecting a balance between aromatic stability and functional reactivity typical in fine chemical building blocks. Laboratories and manufacturing sectors value this type of compound as a raw material for pharmaceutical intermediates, agrochemical research, and sometimes in the production of bespoke specialty chemicals. Experience in organic synthesis shows this molecule can be finicky — its substitution pattern affects both orientation and speed of further chemical reactions.
3,4-Difluoro-2-methoxyphenylacetic acid typically appears as a white to pale yellow solid when pure, sometimes forming crystalline flakes or powder depending on handling and synthesis route. Density typically lands in the range of 1.38 to 1.44 g/cm³, emphasizing its compact aromatic backbone. In my own hands, batches produced with careful crystal-growth conditions render a material that transitions from crystalline powder to small pearl-like flakes under different re-crystallization setups. The melting point often registers near 80–90°C, and the solid stays stable under standard storage. When finely ground, expect it to behave as a soft, almost talc-like material. Unlike more volatile substances, this acid exhibits poor solubility in cold water but dissolves more freely in common organic solvents such as ethanol, acetone, and dichloromethane, which helps in purification and formulation work.
The structure features a methoxy group and two fluorine atoms locked on an aromatic ring, connected to an acetic acid arm. This arrangement influences not only reactivity but also environmental stability. Molecular weight hovers at 202.16 g/mol. From the point of view of chemical synthesis, the presence of electron-withdrawing fluorines can moderate the acidity of the carboxyl function and influence coupling reactions or other downstream modifications. Manufacturers specify purity levels upwards of 98% for use in sensitive pharmaceutical or research applications, and I’ve seen impurities alter both reactivity and, in rare cases, color.
Depending on the production method and grade, this acid appears as a fine-grained powder, irregular flakes, or, less commonly, crystalline lumps. Laboratories frequently encounter this material jarred as a free-flowing solid, protected from moisture, direct light, and oxygen to preserve quality. Some batches come vacuum-sealed to prevent hydrolysis, a best practice rooted in experience handling similar aromatic acids. In terms of volume, commercial producers offer it by kilogram, with density notation often guiding safe and efficient packaging. Transport regulations peg this compound as a non-volatile, stable solid, less hazardous compared to more reactive acid chlorides or nitroaromatics, but personal protective equipment is still essential. Accidental skin contact causes mild irritation sometimes due to the acidity; eye protection and gloves are standard safeguards, echoing chemical safety culture honed in research labs.
Regulatory authorities tag 3,4-Difluoro-2-methoxyphenylacetic acid under HS Code 291639, falling into the class for carboxylic acids and derivatives. This designation shapes how customs treat it during international transport. Material Safety Data Sheets label it as a low-hazard acid under normal conditions. Even so, precautionary measures matter; inhalation of dust in confined spaces could provoke respiratory discomfort, demanding local exhaust ventilation in larger-scale manufacturing. This isn’t a chemical likely to combust, but like all phenylacetic acids, overheating leads to decomposition with acrid fumes. From long practice, I can confirm that proper labeling, secondary containment, and frequent hazard audits keep workplaces safe.
Research chemists working on drug discovery or crop protection reach for this compound as a core building block, drawn by its ready reactivity at the methoxy and carboxylic positions. Fluorinated aromatics often feature prominently in new pharmaceutical agents due to enhanced metabolic stability. Vendors supply the acid in bulk, as raw material for multi-step synthesis, where a single impurity can derail expensive research projects. Electronic records show consistent demand in university research, medicinal chemistry, and the pilot production of active pharmaceutical ingredients (APIs). The properties — from density and solubility to form — steer choices in solvent selection, storage practice, and safety handling, all vital to reliable industrial use. The current supply chain climate puts a premium on well-documented, reproducible batches.
Environmental attention grows as more fluorinated organics enter chemical plants and laboratories worldwide. 3,4-Difluoro-2-methoxyphenylacetic acid does not rank high as a persistent pollutant or toxic inhalant, but it joins a growing list of specialty chemicals tracked for safe disposal and trace residue control. In my work, straightforward protocols involving neutralization followed by local solvent treatment enable waste acid to be rendered inactive. Training on spillage and transparent data on acute toxicity — thankfully low in this molecule — establish confidence among staff. As regulatory focus tightens globally, clear hazard labeling and up-to-date material data sheets remain essential, forming the backbone of responsible chemical management whether in research or industry.
