Synthesis of Multifunctional Aryl(trifloxyalkenyl)iodonium Triflate Salts

Abstract

A convenient procedure for the synthesis of aryl(trifloxyalkenyl)iodonium triflate salts from commercially available (diacetoxyiodo)benzene, trimethylsilyl trifluoromethanesulfonate, and acetylenes under mild conditions was developed. The obtained multifunctional hypervalent vinyliodonium salts equipped with electrophilic and nucleophilic functions could serve as novel C2 synthons for organic transformations. The structure of the iodonium salts was identified by multidimensional NMR spectroscopy and X-ray crystallography.

Diaryliodoniums Salts as Coupling Partners for Transition-Metal Catalyzed C- and N-Arylation of Heteroarenes

“…Diaryliodonium salts are air-and moisture-stable, non-toxic, easy to handle and commercially available or easy to prepare [1][2][3][4][5][6][7][8]. During the last decade, noteworthy improvement in the synthesis and use of diaryliodonium salts has been reported [9][10][11][12][13][14][15][16][17][18][19][20][21]. Owing to their electron-deficient nature at the iodine center and to the excellent leaving-group ability of the iodoarene, diaryliodonium salts are frequently employed as aromatic electrophiles in aryl transfer processes [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38].…”

PhI(OTf)2 Does Not Exist (Yet)**

“…[2] One such derivative with an increasedo xidative capacity is PhI(OTf) 2 which has had reported use as an in situ generateds pecies in solution by severalg roups, including our own. In organic chemistry PhI(OTf) 2 has purported use in formation of hydrazones, [3] oxyaminations, [4] dizaeniums, [5] synthesis of functionalized cyclopropane rings, [6] cyclization of hydroxystilbenes or carboxylic acids, [7] functionalization of acetylenes, [8] aryl CÀHa lkylations, [9] and alpha arylations. [10] We have used it as as tarting complex to form Weiss' reagent, [PhI(Pyr) 2 ] 2 + via displacement of the triflates (Scheme 1).…”

Generation of Mixed Anhydrides via Oxidative Fragmentation of Tertiary Cyclopropanols with Phenyliodine(III) Dicarboxylates

“…As it was shown before by Momose and co-workers [ 51 ], catalytic amounts of triflic acid can greatly enhance the rate of oxidation, probably because of the generation of highly reactive iodonium triflates in situ [ 52 , 53 , 54 ] (Brønsted acid activation of carbonyl group in γ-keto iodonium intermediate A can also contribute to the rate acceleration effect). In our hands, addition of TfOH (1 mol%) tremendously accelerated the oxidation rate in CDCl 3 (Entry 4).…”