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Product Code B3301-2g
Price $63 ex. VAT

A dihalogenated benzoic acid building block

A synthesis intermediate for APIs and polymeric electrolyte membranes


Specifications | MSDS | Literature and Reviews


5-Chloro-2-fluorobenzoic acid (CAS number 394-30-9) is a derivative of benzoic acid substituted with fluoride and chloride groups. 5-Chloro-2-fluorobenzoic acid is used in the molecular design of pyrimidine-based Aurora kinase inhibitor. The chloride substituent in the target molecule enhances the binding affinity to Aurora A, promoting the degradation of oncoproteins.

5-Chloro-2-fluorobenzoic acid also finds its application in the synthesis of poly(phenylene ether)-based electrolyte membranes for proton exchange fuel cells. Firstly, 5-Chloro-2-fluorobenzoic acid is converted to benzoyl chloride using thionyl chloride, followed by Friedel-Crafts reaction with anisole. The polymer is then formed via the nickel-mediated homocoupling reaction. The polymeric electrolyte membrane exhibits high proton conductivity of 8.60 × 10−3 S cm−1 under 30% relative humidity at 80 °C.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated benzoic acid building block

Fluorinated benzoic acid building block

For drug discovery, medicinal chemistry, and fuel cells

competitively priced 394-30-9

Low Cost

Competitively priced, high quality product

High purity 394-30-9

High purity

>98% High purity

General Information


CAS Number 394-30-9
Chemical Formula C7H4ClFO2
Full Name 5-Chloro-2-fluorobenzoic acid
Molecular Weight 174.56 g/mol
Synonyms 2-Fluoro-5-chlorobenzoic acid
Classification / Family Fluorinated building blocks, Benzoic acid building blocks, APIs, Electrolyte membranes

Chemical Structure


5-Chloro-2-fluorobenzoic acid chemical structure, CAS 394-30-9
5-Chloro-2-fluorobenzoic acid chemical structure, CAS 394-30-9

Product Details


Purity 98%
Melting Point Tm = 152 °C – 157 °C
Appearance White powder

MSDS Documentation


5-Chloro-2-fluorobenzoic acid5-Chloro-2-fluorobenzoic acid MSDS Sheet

Literature and Reviews


  1. Polymer electrolyte membranes based on poly(phenylene ether)s with sulfonic acid via long alkyl side chains, X. Zhang et al., J. Mater. Chem. A, 1, 11389–11396 (2013); DOI: 10.1039/C3TA12026K.
  2. Discovery and synthesis of a pyrimidine-based aurora kinase inhibitor to reduce levels of MYC oncoproteins, Y.-H. Chi et al., J. Med. Chem. 2021, 64, 7312–7330 (2021); DOI: 10.1021/acs.jmedchem.0c01806.
  3. Discovery of novel small molecule dual inhibitors targeting toll-like receptor 7 and 8, R. Padilla-Salinas et al., J. Med. Chem., 62 (22), 10221–10244 (2019); DOI: 10.1021/acs.jmedchem.9b01201.
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