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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.
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Hypervalent Iodine‐Mediated Azidation Reactions
Abstract Organic azides have found wide application in various fields of science and technology. This review summarizes recently developed approaches to the direct, one‐step synthesis of diverse organic azides utilizing hypervalent iodine reagents. The first part of review deals with the azidation using unstable azidoiodinanes generatedin situfrom common hypervalent iodine reagents (such as diacetoxyiodobenzene or iodosylbenzene) and a source of azide anion (TMSN3or NaN3). The second part of review is dedicated to the application of stable azidobenziodoxoles as useful azidating reagents that allow selective direct azidation of C−H bonds or double carbon‐carbon bonds under mild reaction conditions. The use of azidobenziodoxoles eliminates the main disadvantages of the traditional approaches to organic azides, such as the need in pre‐functionalization of organic substrates and harsh reaction conditions. Synthetic application of azidobenziodoxoles made possible direct selective azidation of a plethora of organic substrates including complex molecules at the late synthetic stage.
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- Award ID(s):
- 1759798
- PAR ID:
- 10371642
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Organic Chemistry
- Volume:
- 2022
- Issue:
- 34
- ISSN:
- 1434-193X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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