General One‐Pot Synthesis of Alkynyliodonium Salts and Alkynyl Benziodoxolones from Aryl Iodides

Abstract

I: hyperfond of a triple bond! The first one-pot synthesis of alkynyl(aryl)iodonium salts directly from aryl iodides has been developed. The reaction is fast and high yielding, and can be extended to the synthesis of alkynyl benziodoxolones (see scheme). The developed methodology is expected to greatly facilitate the access to this interesting class of hypervalent iodine reagents, and many new application areas are foreseen.

Synthesis, Characterization and Unusual Reactivity of Vinylbenziodoxolones—Novel Hypervalent Iodine Reagents

“…Benziodoxolones are often synthesized in several steps from 2‐iodobenzoic acid, which is oxidized to hydroxybenziodoxolone and then coupled with a suitable regent . We recently published one‐pot syntheses of both alkynyl salts and alkynylbenziodoxolones starting from 2‐iodobenzoic acid and either terminal alkynes or alkynylboronic esters ,…”

Recent advances in alkylidene carbene chemistry

“…90 Moran used this methodology to explore the effect of the aromatic iodine species on migration and insertion reactions of alkylidene carbenes. 91 Superior results were achieved using a 2-anisyl substituent (Scheme 56).…”

Alkynylation with Hypervalent Iodine Reagents

“…The broadest substrate scope was achieved starting from cyano(phenyl)iodonium triflate 4 by Stang and coworkers, but this approach required the use of more toxic alkynyl stannanes (Scheme 2.2, C) [31][32]. Finally, Olofsson and co-workers reported in 2012 a very practical one-pot oxidation-alkynylation protocol starting from iodobenzene 5 and using alkynyl boronic acid esters (Scheme 2.2, D) [33]. A limitation of this method is the use of the sometimes unstable and difficult accessible boronic acid esters.…”

“…Koser and co-workers already reported in 1993 that cyclic hypervalent iodine reagents bearing a more electron-withdrawing sulfonate group could be also easily accessed from the hydroxy derivative 34 using terminal acetylenes and toluene sulfonic acid as activator (Scheme 2.12, D [105]). Finally, Bouma and Olofsson developed in 2012 the first one-pot synthesis of EBX reagents starting directly from 2-iodobenzoic acid 35 (Scheme 2.12, E [33]). metaChloroperbenzoic acid was used as oxidant and alkynyl boronic acid esters as alkyne source.…”