Fluorine as a control element in asymmetric synthesis
Vincent Bizet1, Dominique Cahard2
1UMR 6014 CNRS COBRA, Normandie Université, 1 rue Tesnière, 76821 Mont Saint Aignan, France.
Abstract:
The installation of fluorine atoms in reactants or catalysts has a dramatic impact on reactivity, regioselectivity and stereoselectivity. Several effects account for the modified stereochemical outcome of reactions with fluorinated versus non-fluorinated molecules. These effects are inherent to the specific properties of fluorine such as the size, the electronegativity, the chelation with metal cations, the hydrogen-bonding ability, the electrostatic and stereoelectronic interactions with neighbouring groups. The use of the effects of fluorine for a desirable goal in asymmetric synthesis is exemplified hereafter.
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