Azido, Cyano, and Nitrato Cyclic Hypervalent Iodine(III) Reagents in Heterocycle Synthesis

Abstract

In recent years, synthetic applications of cyclic hypervalent iodine reagents have undergone significant developments. Among them, benziodoxol(on)es containing azido, cyano, and nitrato ligands have been found to be useful synthetic tools for the preparation of functionalized heterocyclic compounds. This review aims to summarize recent synthetic applications of benziodoxol(on)es as effective heteroatom-introducing reagents. Dedicated to Professor Yasuyuki Kita on the occasion of his 77th birthdayCONTENTS 1. Introduction 2. Cyclic hypervalent iodine azide in heterocycle synthesis 3. Heterocycle synthesis using cyclic hypervalent iodine cyanide 4. Recent applications of cyclic hypervalent iodine nitrate 5. Conclusion

Cyclic Hypervalent Iodine-Induced Oxidative Phenol and Aniline Couplings with Phenothiazines

“…Thus, the coupling reaction in the presence of 1-acetoxy-1,2-benziodoxol-3­(1 H )-one, a hypervalent iodine reagent with a cyclic structure, afforded a high yield (88%) of 3a , without peroxidation (entry 5). Furthermore, 1-acetoxy-5-fluoro-1,2-benziodoxol-3­(1 H )-one, − bearing the electron-withdrawing group fluorine, demonstrated improved reactivity, increasing the yield to 92% (entry 6). Iodine reagents bearing electron-donating groups like methoxy groups (entry 7), and those bearing bromo groups that have low solubility (entry 8), decreased the product yield .…”