Iodine(III)‐Mediated Diazidation and Azido‐oxyamination of Enamides

Abstract

In this study we demonstrate that the combination of bis(tert-butylcarbonyloxy)iodobenzene and lithium azide in acetonitrile allows the diazidation of various enamide substrates. The azido-oxyamination of the same substrates can be carried out in the presence of 2,2,6,6-tetramethylpiperidine N-oxide (TEMPO). Control experiments strongly suggest that this latter process occurs through a shift in nature of the in situ generated electrophilic species from a radical to a cation. Finally, the versatility of the novel compounds synthesized was also assessed by running various selective reactions on them.

Regio‐ and Stereoselective Iron‐Catalyzed Oxyazidation of Enamides Using a Hypervalent Iodine Reagent

“…Xu and co‐workers developed an iron(II)‐catalyzed diastereoselective diazidation method for non‐functionalized and highly functionalized olefins . Interesting developments have also been described by the groups of Loh and Dodd in the copper‐catalyzed oxyazidation and diazidation of styrene derivatives. Despite extensive research and significant advances in this field, however, the stereoselective metal‐catalyzed introduction of an azido group into organic compounds remains challenging.…”

“…Metal-catalyzed azidation has emerged therefore as as traightforward and atom-economic strategyt oi nstallv arious nitrogen-based motifs. [9] Interesting developments have also been described by the groupso fL oh [10] and Dodd [11] in the copper-catalyzed oxyazidation and diazidation of styrene derivatives. [6] In 2013, radical azidooxygenationo fv ariouss tyrene derivatives ands pecifically of electron-rich alkenes was achieved by Studerw ith an excellent diastereoselectivity in presenceo fN 3 -iodine(III) and TEMPO-Na.…”

Alkene Difunctionalization Using Hypervalent Iodine Reagents: Progress and Developments in the Past Ten Years

“…Preliminary mechanistic studies have revealed that the reaction proceeds via in situ-generated chlorinated hypervalent iodine species (Scheme 28b) [95]. As an extension of this protocol, a pseudohalide source and TEMPO ((2,2,6,6-Tetramethylpiperidin-1-yl)oxyl) combination resulted in the oxyazidation reaction (Scheme 28c,d) [96].…”

Enol and Ynol Surrogates: Promising Substrates for Hypervalent Iodine Chemistry

“…Lastly, in a series of three publications, Dodd and co‐workers demonstrated the versatility of the reaction of PIDA with disubstituted enamides (Scheme ) . They were able to access α‐halo and α‐azide aminals by performing the reaction in ethanol.…”