tert-Butyl 4-bromo-2-methylbenzoate

tert-Butyl 4-bromo-2-methylbenzoate (CAS 445003-37-2) is a strategically protected halogenated aromatic ester engineered for pharmaceutical intermediate synthesis, agrochemical development, and materials science applications. This molecule integrates a benzoate core—a benzene ring with a tert-butyl ester substituent—with a bromine atom at the C4 position and a methyl group at the C2 position. The tert-butyl ester moiety serves as an acid-labile protecting group for the carboxylic acid, enabling compatibility with base-sensitive reactions and orthogonal deprotection strategies (cleavage via TFA/HCl), while the C4-bromo substituent enables Pd-catalyzed cross-coupling (Suzuki, Stille, Negishi). The ortho-methyl group provides steric modulation and metabolic stability enhancement. Compared to its free acid analog (CAS 68837-59-2), this ester form offers improved lipophilicity and solubility in organic solvents. Compared to its methyl ester analog (CAS 78471-43-9 derivative), the tert-butyl group allows acid-mediated deprotection rather than base-mediated hydrolysis, providing synthetic flexibility. This intermediate is particularly valuable for constructing NSAID analogs, kinase inhibitor cores, and functional materials where controlled acid release and cross-coupling diversification are critical. Manufactured under controlled conditions, it supports drug discovery programs requiring modular access to differentially protected halogenated aromatic acids.

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Product Name	tert-Butyl 4-bromo-2-methylbenzoate
CAS Number	445003-37-2
Chinese Name	4-溴-2-甲基苯甲酸叔丁酯
Synonyms	tert-Butyl 4-bromo-2-methylbenzoate; 4-Bromo-2-methylbenzoic acid tert-butyl ester
Chinese Synonyms	4-溴-2-甲基苯甲酸叔丁酯; 4-溴邻甲苯甲酸叔丁酯
Molecular Formula	C₁₂H₁₅BrO₂
Molecular Weight	271.15 g/mol
Purity	≥ 98% (HPLC/GC area normalization)
Product Category	Pharmaceutical Intermediates / Benzoic Acid Derivatives / Acid-Labile Protected Esters
Appearance	Yellow to orange liquid
Melting Point	~60-65°C (estimated, literature reference recommended)
Storage Conditions	Store in a cool, dry, well-ventilated area away from light and moisture. Keep container tightly closed. Protect from strong acids (TFA, HCl) to avoid premature ester deprotection and from strong bases to avoid hydrolysis.
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, Pd-catalyzed cross-coupling (C4-Br), acid-mediated deprotection studies, agrochemical intermediate synthesis, functional material precursor
Reactivity	Suitable for Pd-catalyzed cross-coupling (C4-Br displacement), ester deprotection (TFA/DCM or HCl/dioxane), electrophilic aromatic substitution at C3/C5/C6, and sequential functionalization
Special Note	✅ Acid-Labile Protected Ester—tert-butyl group enables orthogonal deprotection vs. methyl esters. C4-Br enables cross-coupling. Distinct from free acid (CAS 68837-59-2) by protection status. Part of our halogenated aromatic ester series.