Development of cross-linked polystyrene-supported chiral amines featuring a fluorinated linker for gel-phase 19F NMR spectrometry monitoring of reactions.
Ten cross-linked polystyrene-supported, protected chiral amines featuring both a spacer, comprising from 5 to 15 atoms, and a fluorinated linker have been successfully prepared. The development of the monitoring technique by gel-phase 19F NMR spectrometry on cross-linked polystyrene derivatives proved to be of high value in four steps of the process, as shown by the comparison of data gathered from both a classic NMR spectrometer and elemental analysis. Gel-phase 19F NMR spectrometry, thus, constitutes a useful technique that complements IR and 13C NMR spectrometries for the qualitative monitoring of reactions. In addition, quantitative determination of the conversion in a given transformation is possible, provided that 19F chemical shifts of the substrate and the product be different enough (Deltadelta>base width), as illustrated by the Mitsunobu coupling process (16-->17). The technique is nondestructive, and the samples used to monitor the reactions may be returned to the reaction medium. Deprotection of the above amines was achieved and furnished eight of the final resins in good to acceptable purity for future applications.
Hourdin
Marie
M
Laboratoire des Fonctions Azotées et Oxygénées Complexes and Laboratoire de Chimie Organique Biologique et Structurale, UMR CNRS 6014, IRCOF-Université de Rouen, Rue Tesnières, F-76821 Mont Saint Aignan, France.
Gouhier
Géraldine
G
Gautier
Arnaud
A
Condamine
Eric
E
Piettre
Serge R
SR
D000588:Amines / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D005462:Fluorine Radioisotopes; D005782:Gels; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011137:Polystyrenes / Q000138:chemical synthesis* / Q000737:chemistry; D012117:Resins, Synthetic / Q000138:chemical synthesis* / Q000737:chemistry
D000588:Amines; D003432:Cross-Linking Reagents; D005462:Fluorine Radioisotopes; D005782:Gels; D006845:Hydrocarbons, Fluorinated; D011137:Polystyrenes; D012117:Resins, Synthetic