Intramolecular Fluorocyclizations of Unsaturated Carboxylic Acids with a Stable Hypervalent Fluoroiodane Reagent
Gemma C Geary, Eric G Hope, Alison M Stuart1
1Department of Chemistry, University of Leicester, Leicester, LE1 7RH (UK). Alison.Stuart@le.ac.uk.
Abstract:
A new class of fluorinated lactones was prepared by the intramolecular fluorocyclizations of unsaturated carboxylic acids by using the stable fluoroiodane reagent in combination with AgBF4. This unique reaction incorporates a cyclization, an aryl migration, and a fluorination all in one step. The fluoroiodane reagent, prepared easily from fluoride, can also be used without a metal catalyst to give moderate yields within just 1 hour, thus demonstrating that it is a suitable reagent for developing new (18)F-labelled radiotracers for PET imaging.
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