A variety of alkynylated amines, amides, and imides arereacted in t
he superacid system HF-SbF
5 to give regioselectively new
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-gem-difluoroamines. T
he reaction, w
hic
h isnot observed in pure HF, is consistent wit
h t
he formation ofa dicationic intermediate (i.e., bot
h vinylic and adjacentprotonated
N-ammonium cations). Application to t
he regioselective and efficient synt
hesis of difluorinated cinc
honaalkaloid derivatives is described.