Perfluoroalkyl phenyliodonium salts

Diphenyliodonium chloride, bromide, and iodide Aldrich, Lancaster Perfluoroalkyl phenyliodonium salts TCI America... 

Phenyliodonium Salts with an Aliphatic Moiety Preparative Methods. Reactivity of Perfluoroalkyl Phenyliodonium Salts. Reactivity of Other Iodonium Salts. 

The reaction of enol trimethylsilyl ethers of carbonyl compounds with (a,a-dihydroperfluoroalkyl) phenyliodonium triflates required promotion by potassium fluoride to proceed at room temperature to give the P-perfluoroalkyl carbonyl compounds in good yields.225 in the case of the silyl enol ether of an a,p-unsaturated ketone (119), the 6-perfluoroalkyl-o,p-unsaturated carbonyl compound (120) was the only product formed. The reaction is likely to follow a path similar to the one used in the reaction of silyl enol ethers with (perfluoroalkyl)phenyliodonium salts. In a first step, a ic-complex is formed which evolves into the cationic product of a- or y-addition, followed by desilylation to the carbonyl reaction product. 

Because of the multitude and diversity of iodonium salts and zwitterions, some of which are labile or are prepared for specific purposes, their preparative methods are discussed in Chapter 8, for diaryl iodonium salts and related compounds, Chapter 9 for perfluoroalkyl, alkenyl and alkynyl phenyliodonium salts and Chapter 10 for zwitterionic iodonium compounds. In addition, the preparation of some lesser known reagents, including 2-iodosylbenzoic acid, is given in Chapter 12. 

Alkyl and aryl thiols afforded with perfluoroalkyl iodonium salts in the presence of pyridine the corresponding sulphides in good to excellent yields [25], Several sulphides and sulphoxides upon reaction with trifluoroethyl phenyliodonium triflate were converted into 2,2,2-trifluoroethyl sulphonium salts [26]. 

Attempts to prepare a (/ -fiuorovinyl)iodonium salt from l-decynyl(phenyl)iodonium tetrafluoroborate by the procedures employed for / -chloro- and (/ -bromovinyl)iodonium halides have been unsuccessful103. Admixture of the decynyliodonium salt and lithium fluoride in acetic acid ultimately (2 days, rt) leads to l-acetoxy-2-decanone103. (Z )-(/ -Fluoro-jS-perfluoroalkylvinyl)iodonium triflates, on the other hand, can be made by the treatment of (1H, li/-perfluoroalkyl)phenyliodonium triflates with sodium hydride (equation 178)136. Apart from 2-fluoro-l-hexadecenyl(phenyl)iodonium chloride (synthesis not described)104, these are the only reported examples of (/ -fluorovinyl)iodonium salts. 

A third type of derivatives of iodonium salts, the perfluoroalkyl phenyliodonium (dfluoromethane sulfonates (FITS), showed an enhanced reactivity compared to the chloride and the tetrafluoroborate salts. In a series of papers, Umemoto et al have extensively studied the synthesis of these compounds and their reactivity towards a wide range of more or less powerful nucleophiles. 206 Different mechanistic pathways have been demonstrated to occur in these reactions. Ligand coupling appears to be involved in a number of nucleophilic displacements implying various types of carbanions, thiols and other nucleophilic substrates. 

Like perfluoroalkylation, electrophilic a,a-dihydroperfluoroalkylation can be efficiently performed by the use of the appropriate (a,a-dihydroperfluoroalkyl)phenyliodonium salts. A wide range of nucleophiles were alkylated under mild conditions. Most of the reactions can occur by a ligand coupling taking place on an intermediate trisubstituted iodane(UI) compound. This is the case of the reactions with carbanions, amines, alkoxides, phenoxides, thiolates and carboxylic acid ammonium salts. Dialkylation of aniline was also obtained by using two molar equivalents of the iodonium reagent.219,220 (Table 5.11)... 

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