Stabilization of Ethynyl‐Substituted Aryl‐λ³‐Iodanes by Tethered N‐Heterocylces**

Abstract

A systematic investigation of ethynyl N‐heterocycle‐substituted‐λ3‐iodanes (ENHIs) is presented. In a straightforward one‐pot synthesis these novel reagents can be obtained in high yields bearing a variety of N‐heterocycles. Their reactivity as electrophilic alkyne group transfer reagents was benchmarked in well‐established and novel inter‐ and intramolecular group transfer reactions.

X‐Ray and NMR Structural Data of Ethynylbenziodoxolones (EBXs) Reagents and Their Analogues

“…[19] We also analyzed benziodoxole reagent 3a. Finally, we added the recently developed N-heterocyclic reagents 4a-4c, 6, 7 [20,21] synthesized in our group and the triazole-based reagent 5 [22] reported by the Nachtsheim group (Table 1).…”

Oxidation of benzylic alcohols to carbonyls using N-heterocyclic stabilized λ3-iodanes

“…For getting an indication of a chloride-activated iodane of this type, a mixture of NHI 1a and HCl in EtOAc was stirred for 1 h at 60 °C and an ESI(−) mass spectrum was recorded afterward, showing an ion I-OMe with m/z 337.0 [ 1a – OH + MeO + Cl] − ( Scheme 1c ). It is known that methanol, which is used as a solvent in the mass spectrometer, can be exchanged with the hydroxy group of the NHI [ 21 ]. No such ion was measured in the mixture before heating.…”

“…During the past years, N -heterocycle-stabilized iodanes (NHIs) were demonstrated as suitable tools for various applications among them group transfer reactions [ 21 ] and as building blocks [ 22 – 24 ]. The synthetic potential of NHIs has been previously studied in model transformations such as thioanisole oxygenation, oxidative lactonization, or diacetoxylation of alkenes [ 25 – 28 ].…”

Oxidation of benzylic alcohols to carbonyls using N heterocyclic stabilized λ3-iodanes

“…[16] The use of additives such as bromide salts or Al2O3 can omit this problem and allow selective oxidation to some extent. [17][18][19][20] During the past years, N-heterocycle stabilized iodanes (NHIs) were demonstrated as suitable tools for various applications among them group transfer reactions [21] and as building blocks [22][23][24]. The synthetic potential of NHIs has been previously studied in model transformations such as thioanisole oxygenation, oxidative lactonization, or https://doi.org/10.26434/chemrxiv-2024-t3b6h ORCID: https://orcid.org/0000-0002-3759-2770 Content not peer-reviewed by ChemRxiv.…”