4-Bromo-2-methylbenzoic acid

4-Bromo-2-methylbenzoic acid (CAS 68837-59-2) is a strategically functionalized halogenated aromatic carboxylic acid engineered for pharmaceutical intermediate synthesis, agrochemical development, and materials science applications. This molecule integrates a benzoic acid core—a benzene ring with a carboxylic acid substituent—with a bromine atom at the C4 position and a methyl group at the C2 position (ortho to the carboxylic acid). The carboxylic acid moiety serves as a versatile handle for amide coupling, esterification, or salt formation, while the C4-bromo substituent enables Pd-catalyzed cross-coupling (Suzuki, Stille, Negishi, Sonogashira) or nucleophilic aromatic substitution under appropriate conditions. The ortho-methyl group provides steric modulation, metabolic stability enhancement, and electronic tuning compared to unsubstituted analogs. This intermediate is particularly valuable for constructing NSAID analogs, kinase inhibitor cores, agrochemical actives, and functional materials where the bromo-methyl-benzoic acid motif balances lipophilicity with versatile synthetic reactivity. Manufactured under controlled conditions, it supports drug discovery programs requiring modular access to differentially substituted halogenated aromatic acids.

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Product Name	4-Bromo-2-methylbenzoic acid
CAS Number	68837-59-2
Chinese Name	4-溴-2-甲基苯甲酸
Synonyms	4-Bromo-2-methylbenzoic acid; 2-Methyl-4-bromobenzoic acid; 4-Bromo-o-toluic acid
Chinese Synonyms	2-甲基-4-溴苯甲酸; 4-溴-2-甲基苯甲酸; 4-溴邻甲苯甲酸
Molecular Formula	C₈H₇BrO₂
Molecular Weight	215.04 g/mol
Purity	≥ 98% (HPLC area normalization)
Product Category	Pharmaceutical Intermediates / Benzoic Acid Derivatives / Halogenated Aromatic Acids
Appearance	White to Grayish-White Crystalline Powder or Solid
Melting Point	~155-160°C (literature reference recommended)
pKa	~3.5-4.0 (carboxylic acid, estimated)
Storage Conditions	Store in a cool, dry, well-ventilated area away from light and moisture. Keep container tightly closed. Protect from strong bases to avoid salt formation and from strong oxidizing agents.
Shelf Life	24 months under recommended storage conditions
Packaging	100mg/vial, 500mg/vial, 1g/bottle, 5g/bottle, or customized according to customer requirements
Applications	NSAID analog synthesis, kinase inhibitor development, agrochemical intermediate synthesis, Pd-catalyzed cross-coupling (C4-Br), amide coupling for drug conjugates, functional material precursor
Reactivity	Suitable for carboxylic acid activation (EDC/HATU/DCC), esterification, amide coupling, Pd-catalyzed cross-coupling (C4-Br displacement), electrophilic aromatic substitution at C3/C5/C6, and salt formation
Special Note	✅ Ortho-Methyl Halogenated Acid—2-methyl group provides steric modulation vs. unsubstituted analogs. C4-Br enables cross-coupling diversification. Distinct from pyrazine/piperidine series by aromatic benzoic acid core. Part of our halogenated aromatic acid building block series.