Organosulfonyloxy derivatives of 1,2-benziodoxol-3(1H)-one (3a-c) and 3,3-bis(trifluoromethyl)-3(1H)-1,2-benziodoxole (5a-c) can be prepared in high yield by the reaction of 1-hydroxybenziodoxoles 1 or 4 and the corresponding sulfonic acids or Me(3)SiOTf in the form of stable, but moderately hygroscopic, microcrystalline solids. Reaction of the triflate derivatives 3a and 5a with alkynyltrimethylsilanes affords either alkynyliodonium triflates 6, or (E)-beta-(trifluoromethanesulfonyloxy)alkenyliodonium triflates 7, while the same reaction in the presence of pyridine selectively gives the respective 1-alkynylbenziodoxoles 8 and 9 in 82-90% yield.

Azidoiodinanes 2 and 4a,b can be prepared from the appropriate benziodoxoles 1 and 3a,b and trimethylsilyl azide in the form of stable, crystalline compounds. A single-crystal X-ray analysis for azide 4b revealed the expected hypervalent iodine distorted T-shaped geometry with the N1-I-O bond angle of 169.5 (2) degrees. The lengths of the bonds to the iodine atom, I-N (2.18 Angstrom), I-O (2.13 Angstrom), and I-C (2.11 Angstrom), are within the range of typical single covalent bonds in organic derivatives of polyvalent iodine, while the previously reported benziodoxoles generally have an elongated I-O bond. The geometry of the I-(III)NNN fragment in 4b is similar to the literature electron diffraction data on monomeric iodine azide, IN3, in gas phase. Azidobenziodoxoles 2,4 are potentially useful reagents for direct azidation of organic substrates, such as dimethylanilines, alkanes, and alkenes. Reaction of 2 with dimethylanilines proceeds under mild conditions to afford the respective N-azidomethyl-N-methylanilines in excellent yield. Alkanes, cycloalkanes, and adamantanes react with azidobenziodoxoles 2 or 4b in the presence of radical initiators at 80-132 degrees C with the formation of tertiary alkylazides, while reaction of norbornane lends to exo-2-azidonorbornane. Under similar conditions cyclohexene is selectively azidated at the allylic position.

Cyanobenziodoxols 2 and 4 can be prepared from benziodoxols 1 or 3 and cyanotrimethylsilane in the form of stable, crystalline compounds. Cyanobenziodoxol 2 reacts with N,N-dimethylarylamines under mild conditions to afford N-(cyanomethyl)-N-methylarylamines 6 in excellent yields.

[Hydroxy(sulfonyloxy)iodo]perfluoroalkanes (CnF2n+1I+OH .(-)OSO(2)R, n = 2, 3, 4, 6, 8; R = Me,p-MeC(6)H(4), CF3) can be prepared in two steps from the corresponding perfluoroalkyliodides by oxidation with trifluoroperacetic acid and subsequent reaction with MeSO(2)OH, p-MeC(6)H(4)SO(2)OH, or Me(3)SiOSO(2)CF(3). These compouds react with trimethylsilyl-substituted arenes under mild conditions forming the corresponding perfluoroalkyl(aryl)iodonium salts in good yield.

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Azidoiodinanes 2,4,6 can be prepared from benziodoxols 1,3 and trimethylsilyl azide in the form of stable, crystalline compounds. These compounds are potentially useful reagents for electrophilic azidonation of organic substrates. For example, reaction of azide 6 with cyclohexene affords 2-azidocyclohexanone 7 in moderate yield.

Various aryl(perfluoroalkyl)iodonium salts 3 can be conveniently prepared by the reaction of [hydroxy(sulfonyloxy)iodo]-perfluoroalkanes CnF2n+1I(OH).OSO2R 1 with trimethylsilyl-substituted arenes 2.

1-Organosulfonyloxy-1,2-benziodoxol-3-(1H)-ones (3,4,5) can be prepared in one step from 2-iodosobenzoic acid and the corresponding sulfonic acids or Me(3)SiOTf. Reactions of these compounds with bis(trimethylsilyl)acetylene or cyanotrimethylsilane afford the respective alkynyl or cyano iodonium salts 6, 7, 8.