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Product Code B3271-1g
Price £35 ex. VAT

A fluorinated benzoic acid building block

Used as a molecular scaffold for organic synthesis


4-Fluoro-2-iodobenzoic acid (CAS number 56096-89-0) is a dihalogenated benzoic acid with a fluoride sitting opposite and an iodide next to the carboxylic acid around the hexagonal table of a benzene ring. With its three different functional groups, 4-fluoro-2-iodobenzoic acid serves as a versatile building block. As a result, bioactive bicyclic heterocycles such as phthalide and isocoumarin can be synthesised, using a Sonogashira-type reaction. Isocoumarin as the 6-endo-dig product (according to Balwin’s rule) is selectively formed at 100 °C, whereas phthalide, the 5-exo-dig product, is favoured at a lower temperature of 25 °C.

4-Fluoro-2-iodobenzoic acid is also employed in the synthesis of pseudocyclic benziodoxole tosylates as a hypervalent iodine oxidant for organic synthesis. The product is prepared via a ligand transfer reaction between 4-fluoro-2-iodobenzoic acid and PhI(OH)OTs.

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 organic synthesis

competitively priced 56096-89-0

Low Cost

Competitively priced, high quality product

High purity 56096-89-0

High purity

>98% High purity

General Information

CAS Number 56096-89-0
Chemical Formula C7H4FIO2
Full Name 4-Fluoro-2-iodobenzoic acid
Molecular Weight 266.01 g/mol
Synonyms 2-Iodo-4-fluorobenzoic acid
Classification / Family Fluorinated building blocks, Benzoic acid building blocks, Iodide building blocks, Molecular scaffolds, Organic synthesis, Hypervalent iodine oxidants

Chemical Structure

4-Fluoro-2-iodobenzoic acid chemical structure, CAS 56096-89-0
4-Fluoro-2-iodobenzoic acid chemical structure, CAS 56096-89-0

Product Details

Purity 98%
Melting Point Tm = 143 °C – 147 °C
Appearance Off-white powder

MSDS Documentation

4-Fluoro-2-iodobenzoic acid4-Fluoro-2-iodobenzoic acid MSDS Sheet

Literature and Reviews

  1. Preparation, structure, and reactivity of pseudocyclic benziodoxole tosylates: new hypervalent iodine oxidants and electrophiles, A. Yoshimura et al., Chem. Eur. J., 23, 691 (2017); DOI: 10.1002/chem.201604475.
  2. Enantioselective hydroamination of inactivated terminal alkenes, S. Ma et al., Chem., 8, 532–542 (2022); DOI: 10.1016/j.chempr.2021.12.005.
  3. Chemo- and regioselective benzylic C(sp3)–H oxidation bridging the gap between hetero- and homogeneous copper catalysis, S. Nandi et al., iScience, 25, 104341 (2022); DOI: 10.1016/j.isci.2022.104341.
  4. Regioselective one-pot synthesis of isocoumarins and phthalides from 2-iodobenzoic acid and alkynes by temperature control, M. Kumar et al., Adv. Synth. Catal., 355, 3221–3230 (2013); DOI: 10.1002/adsc.201300561.
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