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The synthesis of substituted 1,4-benzoquinones, a biologically important class of compounds, was developed using [mu]-oxodi(phenyliodanyl) diacetate, a (diacetoxyiodo)benzene-based oxidizing reagent, in order to introduce second-year undergraduate organic laboratory students in their second semester or advanced organic students to increasingly popular and environmentally friendly hypervalent iodine chemistry. This experiment develops on concepts found in the undergraduate organic chemistry curriculum; conveniently fits into approximately two 3 h lab modules; and utilizes regularly found equipment and inexpensive, commercially available chemicals.

A series of new isoxazole‐substituted aryl iodides 1 a–1 d have been synthesized by DIB‐mediated [3+2] cycloaddition reaction of 2‐iodo‐1,3‐bis(prop‐2‐yn‐1‐yloxy) benzene (4) with corresponding benzaldehyde oximes 5 a–5 d. Structure of the synthesized aryl iodides 1 were characterized by IR, 1H NMR, 13C NMR and HRMS. The structure of 1 a was also confirmed by single‐crystal X‐ray crystallography. Further, catalytic activity of iodoarenes 1 a–1 d was screened for the oxidation of hydroquinones and sulfides. On oxidation using aryl iodides 1 with m‐CPBA as terminal oxidant, hydroquinones afforded benzoquinones while sulfides gave corresponding sulfoxides in good to excellent yields. Iodoarene 1 b showed the best catalytic activity for the oxidation of sulfides and hydroquinones. Moreover, iodoarene 1 b, was also utilized for α‐oxytosylation of acetophenones. [ABSTRACT FROM AUTHOR]

We report a greener peptide coupling using bicyclic benziodazolone and triarylphosphine as coupling reagents. Bicyclic benziodazolone also works as a base and can be recovered as the corresponding iodine(I) compound after use, which can be converted to the original iodine(III) reagent by electrolytic oxidation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Dehydrogenative cycloisomerization/arylation sequence of heteroatom nucleophile‐tethered unactivated alkynes provides a facile and powerful approach to C−C bond formation between the generated heterocycles and unfunctionalized arenes. Here, we describe a hypervalent iodine(III)‐catalyzed synthesis of oxazoles concomitant with the introduction of aryl groups into side chain from N‐propargyl carboxamides and arenes, representing first C(sp3)−C(sp2) bond formation by the catalytic dehydrogenative cycloisomerization/arylation reaction in exo‐dig modes. [ABSTRACT FROM AUTHOR]

Hypervalent iodine (HVI) reagents have gained much attention as versatile oxidants because of their low toxicity, mild reactivity, easy handling, and availability. Despite their unique reactivity and other advantageous properties, stoichiometric HVI reagents are associated with the disadvantage of generating non-recyclable iodoarenes as waste/co-products. To overcome these drawbacks, the syntheses and utilization of various recyclable hypervalent iodine reagents have been established in recent years. This review summarizes the development of various recyclable non-polymeric, polymer-supported, ionic-liquid-supported, and metal–organic framework (MOF)-hybridized HVI reagents. 1 Introduction 2 Polymer-Supported Hypervalent Iodine Reagents 2.1 Polymer-Supported Hypervalent Iodine(III) Reagents 2.2 Polymer-Supported Hypervalent Iodine(V) Reagents 3 Non-Polymeric Recyclable Hypervalent Iodine Reagents 3.1 Non-Polymeric Recyclable Hypervalent Iodine(III) Reagents 3.2 Recyclable Non-Polymeric Hypervalent Iodine(V) Reagents 3.3 Fluorous Hypervalent Iodine Reagents 4 Ionic-Liquid/Ion-Supported Hypervalent Iodine Reagents 5 Metal–Organic Framework (MOF)-Hybridized Hypervalent Iodine Reagents 6 Conclusion [ABSTRACT FROM AUTHOR]

The authors review the publications on polyvalent iodine compounds' organic chemistry. The topics of interest include different classes of polyvalent iodine compound and their synthetic application.