Phenylations, diphenyliodonium triflate

It has been reported that diphenyliodonium triflate reacts with the lithium enolates of some cyclic ketones in the presence of copper cyanide to yield the corresponding a-phenylated or a-diphenylated ketones.58 There has been a detailed analysis of the products of thermal decomposition of diphenyliodonium tetrafluoroborate and hexafluorophosphate salts.59... 

Diphenyliodonium 2-carboxylate [34] and (phenyl)[2-(trimethylsilyl)phenyl] iodonium triflate [35] form benzyne upon heating and treatment with a fluoride source, e.g., tetrabutylammonium fluoride (TBAF), respectively. The benzyne can be trapped with heteroatom and carbon nucleophiles. Benzyne formation has also been observed with other Ar2lX [36]. 

Oxidative addition of diphenyliodonium salt, Ph2lOTf, to PtMe2(bipy) produces the Pt(iv) complex with methyl, phenyl, and triflate ligand 930, and the product reacts with Nal to form a mixture of structural isomers of octahedral Pt(iv) complexes 931 and 932 (Scheme 115). The analogous platinacyclopentane complexes also undergo the oxidative addition to afford Pt(iv) metallacycles with OTf and I ligands 933 and 934. ... 

Direct a-Phenylations of Cyclic Ketones. Copper enolates obtained by reaction of the corresponding lithiate with stoichiometric amounts of anhydrous copper cyanide react with diphenyliodonium triflate to afford Q ,Q -diphenylated or a-phenylated ketones in moderate yields. Five-membered cyclic ketones gave only Q, o -diphenylated compounds, whereas larger cyclic ketones afford only cK-phenylated products (eq 1). It is noteworthy that copper enolates afford the best yields of phenylated compounds. 

Various a-phenylated cyclohexanones have also been prepared in high yields by reaction of the corresponding lithium enolates with diphenyliodonium triflate (eq 2). The cis/trans ratio depends on the nature of the R group. For example, 4-ferf-butylcyclohexanone affords the phenylated product with a cisitrans ratio >20 1, whereas the ratio is only 5 1 in the case of 4-phenylcyclohexanone and 1 15 if cyclohexanone bears a OTBDMS group at C4. 

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