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3-Fluoro-4-methoxybenzoic acid

CAS Number 403-20-3

Fluorinated Building Blocks, Materials, Monomers


Product Code B2821-5g
Price $113 ex. VAT

A fluorinated benzoic acid building block

For applications as an intermediate in the preparation of APIs giving treatment of Alzheimer's disease.


Specifications | MSDS | Literature and Reviews


3-Fluoro-4-methoxybenzoic acid (CAS number 403-20-3) is a fluorinated para-anisic acid derivative. The fluoride substituent enables nucleophilic aromatic substitution, while most of the reactivity centred on the carboxylic group. 3-Fluoro-4-methoxybenzoic acid can undergo various reactions, including Fischer esterification affording esters with ligustrazine moiety for the treatment of Alzheimer's disease.

Furthermore, 3-Fluoro-4-methoxybenzoic acid can be transformed into benzoyl chloride using thionyl chloride to enhance its reactivity, thereby providing a platform for Friedel-Craft acylation reaction. Additionally, 3-Fluoro-4-methoxybenzoic acid can be modified into hydrazide which is used in the synthesis of oxadiazoles for antimicrobial applications.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated building block

Fluorinated benzoic acid building block

for drug discovery, medicinal chemistry and biochemistry research

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High purity 403-20-3

High purity

>98% High purity

General Information


CAS Number 403-20-3
Chemical Formula C8H7FO3
Full Name 3-Fluoro-4-methoxybenzoic acid
Molecular Weight 170.14 g/mol
Synonyms 3-Fluoro-p-anisic Acid
Classification / Family Fluorinated building blocks, Benzoic acid building blocks, Anisic acid building blocks, APIs

Chemical Structure


3-Fluoro-4-methoxybenzoic acid chemical structure, CAS 403-20-3.
3-Fluoro-4-methoxybenzoic acid chemical structure, CAS 403-20-3

Product Details


Purity 98%
Melting Point Tm = 211 °C – 213 °C
Appearance White powder

MSDS Documentation


3-Fluoro-4-methoxybenzoic acid3-Fluoro-4-methoxybenzoic acid MSDS Sheet

Literature and Reviews


  1. 3,5-Dialkoxypyridine analogues of bedaquiline are potent antituberculosis agents with minimal inhibition of the hERG channel, H. Sutherland et al., Bioorg. Med. Chem., 27, 1292–1307(2019); DOI: 10.1016/j.bmc.2019.02.026.
  2. Studies on dibenzylamines as inhibitors of Venezuelan Euinine encephalitis virus, T. Nguyen et al., ACS Infect. Dis., 5(12), 2014–2028(2019); DOI: 10.1021/acsinfecdis.9b00035.
  3. Synthesis, characterization, and pharmacological screening of new 1,3,4-oxadiazole derivatives possessing 3-fluoro-4-methoxyphenyl moiety, Shivapura et al., Monatsh. Chem., 146, 207–214(2015); DOI: 10.1007/s00706-014-1291-9.
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