Efficient Synthesis and Ring-Opening Reactions of Monofluorinated Epoxides Derived from α-Fluorosulfoximines

Monofluorinated epoxides were successfully prepared through the O-cyclization reaction between alpha-fluorosulfoximines and ketones. The obtained fluoroepoxides were found to readily undergo an interesting ring-opening process (involving both a C-F bond cleavage and another C-F bond formation) in the presence of titanium tetrafluoride or pyridinium poly(hydrogen fluoride) to afford alpha-fluorinated ketones. The later process constitutes a formal catalytic 1,2-fluorine shift reaction.