Bis-iodonium species

A number of interesting bis-iodonium acetylenes and bis-iodonium diynes were reported in the early 1990s. Reaction of bis-tin-acetylene 29 and bis-tin-diyne 31 with two equivalents of 7 in cold dichloromethane results in the formation of novel bis-iodonium ethyne 30 [24] and bis-iodonium diyne 32 [39], respectively [Eqs. (15), (16)]. 

Similarly, tethered conjugated as well as nonconjugated bis-iodonium diyne bistriflates 34, 35 [40], and ditosylates 36 [41], have been reported [Eqs. (17), (18)]. Reaction of the respective bis-tin-alkynes with two equivalents of 7 results in good to excellent yield of the corresponding bis-iodonium diynes 34-36. 

Likewise, the reaction [42] of three equivalents of 7 with the tris-tin-alkyne 37 in cold dichloromethane gives the symmetrical tris-iodonium salt 38 [Eq. (19)]. 

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