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Abstract Hypervalent iodine compounds have found broad application in modern organic chemistry as reagents and catalysts. Cyclic hypervalent iodine reagents based on the benziodoxole heterocyclic system have higher stability compared to their acyclic analogues, which makes possible the preparation and safe handling of the reagents with special ligands such as azido, cyano, and trifluoromethyl groups. Numerous iodine‐substituted benziodoxole derivatives have been prepared and utilized as reagents for transfer of the substituent on hypervalent iodine to organic substrate. Reactions of these reagents with organic substrates can be performed under metal‐free conditions, in the presence of transition metal catalysts, or using photocatalysts under photoirradiation conditions. In this review, we focus on the most recent synthetic applications of cyclic hypervalent iodine(III) reagents with the following ligands: N₃, NHR, CN, CF₃, SCF₃, OR, OAc, ONO₂, and C(=N₂)CO₂R. The review covers literature published mainly in the last 5 years. 

This study provides a greener peptide coupling method using triarylphosphine and recyclable bicyclic benziodazolone, which acts as an oxidant for phosphine as well as base. 

Hypervalent iodine reagents are in high current demand due to their exceptional reactivity in oxidative transformations, as well as in diverse umpolung functionalization reactions. Cyclic hypervalent iodine compounds, known under the general name of benziodoxoles, possess improved thermal stability and synthetic versatility in comparison with their acyclic analogs. Aryl-, alkenyl-, and alkynylbenziodoxoles have recently received wide synthetic applications as efficient reagents for direct arylation, alkenylation, and alkynylation under mild reaction conditions, including transition metal-free conditions as well as photoredox and transition metal catalysis. Using these reagents, a plethora of valuable, hard-to-reach, and structurally diverse complex products can be synthesized by convenient procedures. The review covers the main aspects of the chemistry of benziodoxole-based aryl-, alkynyl-, and alkenyl- transfer reagents, including preparation and synthetic applications. 

2-Iodosylbenzoic acid in the presence of trifluoromethanesulfonic anhydride is an efficient oxidant and electrophilic reagent useful for preparation of the corresponding alkenyl and aryliodonium salts. Compared to the previously reported methods of electrophilic activation of 2-iodosylbenzoic acid, this procedure is compatible with acid-sensitive functional groups, requires mild reaction conditions, and affords products in higher yields.