Stabilization of Ethynyl-Substituted Aryl-λ3-Iodanes by Tethered N-Heterocylces

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 as well as novel inter- and intramolecular group transfer reactions and compared to literature-known ethynyl benziodoxolones.