Enantioselective Construction of Tertiary Fluoride Stereocenters by Organocatalytic Fluorocyclization
Qiang Wang1, Marvin Lübcke1, Maria Biosca1
1Department of Organic Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
Abstract:
1,1-Disubstituted styrenes with internal oxygen and nitrogen nucleophiles undergo oxidative fluorocyclization reactions with in situ generated chiral iodine(III)-catalysts. The resulting fluorinated tetrahydrofurans and pyrrolidines contain a tertiary carbon-fluorine stereocenter. Application of a new 1-naphthyllactic acid-based iodine(III)-catalyst allows the control of tertiary carbon-fluorine stereocenters with up to 96% ee. Density functional theory calculations are performed to investigate the details of the mechanism and the factors governing the stereoselectivity of the reaction.
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