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Product Code B3381-5g
Price £45 ex. VAT

A fluorinated benzoic acid building block

Utilised as a synthesis intermediate for APIs and as a substrate in organic synthesis


Specifications | MSDS | Literature and Reviews


5-Fluoro-2-methylbenzoic acid (CAS number 33184-16-6) is a fluorinated ortho-toluic acid. 5-Fluoro-2-methylbenzoic acid reacts with saturated ketones in a bimetallic Ir/Cu catalytic reaction to afford phthalide, a bicyclic heterocycle used in dyes and fungicides. Additionally, 5-fluoro-2-methylbenzoic acid is involved in the synthesis of benzamide derivatives as HIV-1 integrase inhibitors for antiviral treatment.

5-Fluoro-2-methylbenzoic acid is also utilized in the synthesis of 3-arylisoquinolinones with benzonitrile through a lithiation reaction. The resulting 3-arylisoquinolinones exhibit antiproliferative activity against cancer cells. These molecules bind to microtubules, suppress tubulin polymerization and induce apoptosis in cancer cells.

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 biochemistry

competitively priced 33184-16-6

Low Cost

Competitively priced, high quality product

High purity 33184-16-6

High purity

>98% High purity

General Information


CAS Number 33184-16-6
Chemical Formula C8H7FO2
Full Name 5-Fluoro-2-methylbenzoic acid
Molecular Weight 154.14 g/mol
Synonyms 5-Fluoro-o-toluic acid, 2-Methyl-5-fluorobenzoic acid
Classification / Family Fluorinated building blocks, Benzoic acid building blocks, APIs, Bicyclic heterocycles

Chemical Structure


5-Fluoro-2-methylbenzoic acid chemical structure, CAS 33184-16-6
5-Fluoro-2-methylbenzoic acid chemical structure, CAS 33184-16-6

Product Details


Purity 98%
Melting Point Tm = 130 °C – 132 °C
Appearance White powder

MSDS Documentation


5-Fluoro-2-methylbenzoic acid5-Fluoro-2-methylbenzoic acid MSDS Sheet

Literature and Reviews


  1. Iridium/copper-catalyzed oxidative C−H/O−H annulation of benzoic acids with saturated ketones for accessing 3-substituted phthalides, R. Wang et al., ChemCatChem, 12, 5907 (2020); DOI: 10.1002/cctc.202001214.
  2. Design of HIV-1 integrase inhibitors targeting the catalytic domain as well as its interaction with LEDGF/p75: a scaffold hopping approach using salicylate and catechol groups, X. Fan et al., Bioorg. Med. Chem., 19 (16), 4935–4952 (2011); DOI: 10.1016/j.bmc.2011.06.058.
  3. Validating and enabling phosphoglycerate dehydrogenase (PHGDH) as a target for fragment-based drug discovery in PHGDH-amplified breast cancer, J. Unterlass et al., Oncotarget, 9 (17), 13139–13153 (2018); DOI: 10.18632/oncotarget.11487.
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