EPZ-10 catalyzed regioselective transformation of alkenes into β-iodo ethers, iodohydrins and 2-iodomethyl-2,3-dihydrobenzofurans

Application of Electrochemical Processes to Classical Iodocyclisation: Utility for Selectivity and Mechanistic Insight

“…Pleasingly, in all cases, cyclisation occurred smoothly and in good yield (Table ). Although these reactions take longer than the most comparable in the literature, yields are generally higher, probably due to the slow generation of iodine in situ leading to a lower and more even concentration of the reagent compared to the addition of the bulk reagent.…”

“…61–63 ° C (lit. : 62–63.3 °C); 1 H NMR (400 MHz, CDCl 3 ) δ=6.76‐6.73 ( m , 1H, Ar H ), 6.71‐6.64 ( m , 2H, Ar H ), 4.84 ( dddd , J =9.0, 7.5, 6.6, 4.9 Hz, 1H, OC H ), 3.75 ( s , 3H, OC H 3 ), 3.45–3.29 ( m , 3H, C H α H β , IC H 2 ), 3.01 ( dd , J =16.1, 6.6 Hz, 1H, CH α H β ) ppm. Data in agreement with literature …”

“…With our own research interests in practical electrochemical processes we here report an efficient route for the construction of the dihydrobenzofuran framework through an iodoetherification reaction of 2‐allylphenols where the molecular iodine and a Lewis acid are electrochemically generated from benign starting materials. Examples of iodocyclisation of phenols onto alkenes are conspicuously sparse in the literature with only a few examples being noted . Unlike other iodocyclisation reactions in organic media, those employing alkenes and phenolic nucleophiles require a Lewis acid additive (which can be toxic such as a Hg(II) salt) suggesting an alternative mechanistic pathway compared to classical reactions which are usually rapid and do not require a Lewis acid additive.…”

“…Examples of iodocyclisation of phenols onto alkenes are conspicuously sparse in the literature with only a few examples being noted. [14][15] Unlike other iodocyclisation reactions in organic media, those employing alkenes and phenolic nucleophiles require a Lewis acid additive (which can be toxic such as a Hg (II) salt) suggesting an alternative mechanistic pathway compared to classical reactions which are usually rapid and do not require a Lewis acid additive. We were also keen to see if we could further explore this mechanistic pathway as well as developing a new reaction process.…”

Iodocyclization of Diallyl-Dihydroxy Naphthalenes Using <i>N</i>-Iodosuccinimide vs Molecular Iodine in Aqueous Micelle

“…There are only few reports of the iodine-mediated heterocyclization in aqueous media [30,31] and also in organic media using additives [32,33] such as Envirocat EPZ-10 R or SnCl 4 [34][35][36]. The limitation of the traditional methods may be overcome by using surfactants as cosolvents.…”