Synthesis of Chiral Tertiary Allylic- and Propargylic Fluorides from Nonaflates of Chiral α-Fluorinated β-Keto Dicarbonyl Compounds.

The acetyl group of chiral α-fluorinated dicarbonyl compounds was transformed to nonaflates through a reaction with perfluorobutanesulfonyl fluoride in the presence of DBU in 82-95% yield. These nonaflates were used in Suzuki and Sonogashira coupling reactions to afford chiral tertiary allylic fluorides bearing gem -disubstituted terminal alkenes with excellent optical purities (45-91%, ≥94% ee ). In addition, chiral tertiary propargylic fluorides were obtained from the reaction of nonaflates with DBU (73-86%, ≥94% ee ).