Chemical Identity and Physical Properties

2-Chloro-5-(trifluoromethyl)benzaldehyde (CAS 336100-07-3; Aladdin SKU C120919) is an aromatic aldehyde with the molecular formula C₈H₄ClF₃O and a molecular weight of approximately 208.56 g/mol. The compound bears three distinct functional handles on the benzene ring: an aldehyde group at the 1-position, a chloro substituent at the 2-position (ortho to the aldehyde), and a trifluoromethyl group at the 5-position (para to chlorine).

The combined electron-withdrawing effect of the –CF₃ group and the ring chloride significantly reduces electron density at the aldehyde carbon, enhancing electrophilicity relative to unsubstituted benzaldehyde. This electronic activation facilitates nucleophilic addition reactions, including condensations with active methylene compounds and amine-based transformations.

The compound is expected to be a colorless to pale yellow liquid or low-melting solid at room temperature. Exact melting point, boiling point, and density values should be confirmed from the Certificate of Analysis (CoA) supplied with each batch; refer to Aladdin's product datasheet for C120919 for lot-specific physical data.

Storage, Handling, and Safety Guidelines

Storage: Store 2-Chloro-5-(trifluoromethyl)benzaldehyde in a tightly sealed container under cool, dry conditions, away from direct light and incompatible materials such as strong oxidizers and strong bases. A storage temperature of 2–8 °C or as specified on the product label is recommended to minimize aldehyde oxidation and hydrolysis. Always consult the Safety Data Sheet (SDS) for C120919 before first use.

Handling: Work in a well-ventilated fume hood wearing appropriate personal protective equipment (PPE): chemical-resistant gloves (e.g., nitrile or neoprene), safety goggles, and a laboratory coat. Aldehydes and halogenated aromatics can cause skin and eye irritation; avoid inhalation of vapors. Use stainless steel or glass equipment; avoid prolonged contact with reactive metals.

Waste disposal: Dispose of waste material in accordance with local, regional, and national regulations governing halogenated organic solvents and fluorinated compounds. Do not pour down the drain without verifying local guidelines.

Note: Specific GHS hazard classifications, pictograms, H-statements and P-statements are listed on the Aladdin SDS for C120919. Always retrieve the current SDS from Aladdin Scientific prior to use.

Synthetic Applications and Research Uses

The dual electrophilic character of 2-Chloro-5-(trifluoromethyl)benzaldehyde—arising from the reactive aldehyde and the activating aryl chloride—makes it a multifunctional building block across several reaction classes:

• Knoevenagel and Aldol-type condensations: The electron-deficient aldehyde reacts readily with active methylene compounds (malononitrile, malonate esters, cyanoacetate derivatives) under mild base catalysis to afford arylidene intermediates, which are precursors to heterocyclic scaffolds and push–pull alkenes.
• Reductive amination: Reaction with primary or secondary amines in the presence of a hydride reductant (e.g., NaBH₃CN or NaBH(OAc)₃) provides secondary or tertiary benzylamines bearing the –CF₃ pharmacophore, a motif common in CNS-targeted drug candidates.
• Imine and Schiff base formation: Condensation with aromatic or aliphatic amines gives stable imines that serve as ligands in metal-catalysis or as intermediates toward pharmaceutically relevant nitrogen heterocycles.
• Palladium-catalyzed cross-coupling: The aryl chloride can participate in Suzuki–Miyaura, Buchwald–Hartwig, or Heck reactions under optimized Pd/ligand conditions, enabling introduction of diverse aryl, heteroaryl, or amino substituents while retaining the –CHO and –CF₃ groups for further elaboration.
• Materials and agrochemical research: Fluorinated aromatic aldehydes are used as precursors to liquid-crystal materials, fluorescent probes, and agrochemical active ingredients.

Researchers should optimize reaction conditions (solvent, temperature, catalyst loading) empirically, as the ortho-chloro group may introduce steric effects in reactions at or near the aldehyde position.

Quality, Purity, and Specification Considerations

For demanding synthetic applications, purity is a critical variable. When ordering 2-Chloro-5-(trifluoromethyl)benzaldehyde (C120919) from Aladdin Scientific, consider the following:

• Purity specification: Confirm the purity grade (e.g., ≥97% or ≥98% by GC or HPLC) from the product listing or CoA. Higher-purity material is recommended for catalytic reactions where trace impurities (e.g., chlorinated by-products or residual acid) may deactivate catalysts or introduce side reactions.
• Water content: Aldehyde-containing compounds can undergo slow hydration or oxidation to the corresponding carboxylic acid upon exposure to moisture or air. Check lot-specific CoA for water content (Karl Fischer) if moisture-sensitive protocols are employed.
• NMR and GC confirmation: For new lots, a quick ¹H NMR spectrum (CDCl₃) should show a characteristic aldehyde singlet near δ 10.3–10.5 ppm, along with aromatic multiplets and the absence of acid –OH signals. GC purity analysis confirms absence of significant volatile impurities.
• Packaging and lot traceability: Aladdin Scientific provides batch-specific CoAs. Record the lot number in your lab notebook to ensure full traceability for regulatory or publication purposes.