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Product Code B2351-500mg
Price $95 ex. VAT

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A fluorinated proline with two chiral centres

A synthesis intermediate for APIs, Schiff bases, catalysts and 19F NMR probes


N-Boc-trans-4-fluoro-l-proline (CAS number 203866-14-2) is a bulky Boc (tert-butoxycarbonyl) group protected l-proline with a fluoride substituent at 4-position. N-Boc-trans-4-fluoro-l-proline is a trans-configured diastereomer, meaning that the fluoride and carboxylic acid are on the opposite sides of the molecule. N-Boc-trans-4-fluoro-l-proline reacts with 2-fluoro-5-nitrobenzaldehyde (nucleophilic aromatic substitution) producing a 19F NMR chiral probe to determine the enantiomeric purity of chiral amino acids. N‑Arylsulfonyl‑l‑proline derivatives synthesized from N-Boc-trans-4-fluoro-l-proline is applied as a potent and selective αvβ1 integrin inhibitors. It shows inhibitive performance at half maximal inhibitory concentration (IC50) of 0.02 nM.

The carboxylic acid and the secondary amine of N-Boc-trans-4-fluoro-l-proline can coordinate to metal centres, forming a stable 5-membered ring. A Pd (II) complex with l-proline ligands has been explored yielding enantiomeric excess up to 24% in catalytic olefination reaction.

Multiple functional groups

Multiple functional groups

For facile synthesis

Fluorinated building block

Fluorinated L-proline building block

For drug discovery, NMR probe and organic synthesis

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High purity 203866-14-2

High purity

>97% High purity

General Information

CAS Number 203866-14-2
Chemical Formula C10H16FNO4
Full Name (2S,4R)-1-tert-Butoxycarbonyl-4-fluoro-2-pyrrolidinecarboxylic acid
Molecular Weight 233.24 g/mol
Synonyms N-(tert-Butoxycarbonyl)-trans-4-fluoro-l-proline, (4R)-1-(tert-Butoxycarbonyl)-4-fluoro-l-proline, Boc-4F-l-Proline
Classification / Family Fluorinated building blocks, Heterocyclic building blocks, Chiral building blocks, APIs, Schiff bases, Catalysts, 19F NMR probe

Chemical Structure

N-Boc-trans-4-fluoro-L-proline chemical structure, CAS 203866-14-2
N-Boc-trans-4-fluoro-l-proline chemical structure, CAS 203866-14-2

Product Details

Purity 97%
Melting Point Tm = 115  119 °C
Optical Rotation -70.69 ° (c = 1, methanol)
Appearance White to off-white powder

MSDS Documentation

N-Boc-trans-4-fluoro-L-prolineN-Boc-trans-4-fluoro-l-proline MSDS Sheet

Literature and Reviews

  1. Exploring N-arylsulfonyl-L-proline scaffold as a platform for potent and selective αvβ1 integrin inhibitors, N. Reed et al., ACS Med. Chem. Lett., 7, 902−907(2016); DOI: 10.1021/acsmedchemlett.6b00196.
  2. Synthesis, Ni(II) Schiff base complexation and structural analysis of fluorinated analogs of the ligand (S)-2-[N-(N'-benzylprolyl)amino]benzophenone (BPB), N. Tatum et al., J. Fluor. Chem., 173, 77−83(2015); DOI: 10.1016/j.jfluchem.2015.02.007.
  3. Synthesis, structure, and catalytic reactivity of Pd(II) complexes of proline and proline homologes, D. Hobart et al., Catalysts, 9, 515(2015); DOI: 10.3390/catal9060515.
  4. Trans-4-fluoro-L-proline: a sensitive 19F NMR probe for the rapid simultaneous enantiomeric analysis of multicomponent amines, B. Huang et al., Anal. Chem., 94(3), 1867–1873(2022); DOI: 10.1021/acs.analchem.1c04823.

To the best of our knowledge the information provided here is accurate. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. Products may have minor cosmetic differences (e.g. to the branding) compared to the photos on our website. All products are for laboratory and research and development use only.

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