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Product Code B1681-5g
Price £100 ex. VAT

A fluorinated indole

Used as a synthesis intermediate for dyes and APIs in application of drug discovery, OLEDs, DSSCs and bioimaging


Specifications | MSDS | Literature and Reviews


4-Fluoroindole (CAS number 387-43-9) is a mono-fluorinated indole, a benzene ring fused pyrrole heterocyclic compound. The derivatization of indole is versatile. Substitution of 1-position (on the nitrogen) is achieved with sodium hydride or potassium hydride making it a nucleophile. The 3-position can be activated with a Grignard reagent, namely methylmagnesium bromide or an organozinc compound. Position 2 of indole can be modified via directed ortho lithiation. After the expansion of chromophore, indole derivatives, triazatruxenes, are used as a donor unit in dye-sensitized solar cell with power conversion efficiency (PCE) of 13.6%.

Chemical structure of 4-fluoroindole with labelled positions
Chemical structure of 4-fluoroindole with labelled positions

Indole is an intercellular signal molecule; hence it is a promising pharmaceutical molecular scaffold for active pharmaceutical ingredients (APIs). 4F-Indole improves the effectiveness of kanamycin (an aminoglycoside antibiotic) against Pseudomonas aeruginosa, a multi-drug resistant pathogen.

Combining the photophysio-properties and bioactivity, 4-fluoroindole is use in bioimaging, for instance monitoring cancer cells under anti-cancer treatments.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated building block

Fluorinated indole building block

For drug discovery, OLEDs, and solar cells

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High purity 387-43-9

High purity

>98% High purity

General Information


CAS Number 387-43-9
Chemical Formula C8H6FN
Full Name 4-Fluoro-1H-indole
Molecular Weight 135.14 g/mol
Synonyms N/A
Classification / Family Fluorinated building blocks, Heterocyclic building block, APIs, OLEDs, DSSCs, Bioimaging

Chemical Structure


4-Fluoroindole chemical structure, CAS 387-43-9
4-Fluoroindole chemical structure, CAS 387-43-9

Product Details


Purity 98%
Melting Point Tm = 30 °C – 32 °C
Appearance White powder

MSDS Documentation


4-Fluoroindole MSDS Sheet4-Fluoroindole MSDS Sheet

Literature and Reviews


  1. 4F-Indole enhances the susceptibility of pseudomonas aeruginosa to aminoglycoside antibiotics, Q. Dou et al., Microbiol. Spectr., 11(2), e04519–e04522(2023); DOI: 10.1128/spectrum.04519-22.
  2. Fine tuning of blue photoluminescence from indoles for device fabrication, J. Hwu et al., J. Mater. Chem., 19, 3084–3090(2009); DOI: 10.1039/b821246e.
  3. Indole fused heterocycles as sensitizers in dye-sensitized solar cells: an overview, P. Nitha et al., Mater. Adv., 2, 6136(2021); DOI: 10.1039/d1ma00499a.
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