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Product Code B2351-500mg
Price £76 ex. VAT

A fluorinated proline with two chiral centres

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


Specifications | MSDS | Literature and Reviews


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.
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