Iodoarene difluoride

Both ( )- and (Z)-(2-fluoro-l-alkenyl)iodonium salt 55 (X = I Ar) can be prepared stereoselectively. ( )-(2-Fluoro-l-dodecyl)iodonium salt 55b is prepared by the addition of iodoarene difluoride to 1-dodecyne [84, 85]. On the other hand, (Z)-55b was prepared from the l-dodecynyUodonium salt by a reaction with aqueous HF [86] or metal fluoride [87, 88] (Scheme 25). 

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