First stereospecific synthesis of (E)- or (Z)-alpha-fluoroenones via a kinetically controlled Negishi coupling reaction.
A highly stereospecific synthesis of (E)- or (Z)-alpha-fluoro-alpha,beta-unsaturated ketones 4, via a kinetically controlled Negishi palladium-catalyzed coupling reaction, was developed, providing an easy and general access to valuable fluorinated intermediates (pharmaceutical, peptide mimic, and so on). The synthesis involved a reaction between E/Z gem-bromofluoroolefins 2 and alkoxyvinylzinc species 6 under controlled reaction temperature. At 10 degrees C, (Z)-4 (70 to 99% yields) was obtained along with unreacted (Z)-2 (66 to 99% yields). At THF reflux, the recovered olefin was transformed into (E)-4 (up to 98% yield).
Dutheuil
Guillaume
G
IRCOF-ECOFH, UMR CNRS 6014, INSA de ROUEN, rue Tesnière, 76131 Mont-Saint-Aignan, France.
Paturel
Clotilde
C
Lei
Xinsheng
X
Couve-Bonnaire
Samuel
S
Pannecoucke
Xavier
X
D005461:Fluorine / Q000737:chemistry*; D006838:Hydrocarbons / Q000737:chemistry*; D007700:Kinetics; D015394:Molecular Structure
D006838:Hydrocarbons; D005461:Fluorine