Starting from the early 1990’s, the chemistry of polyvalent iodine organic compounds has experienced an explosive development. This surging interest in iodine compounds is mainly due to the very useful oxidizing properties of polyvalent organic iodine reagents, combined with their benign environmental character and commercial availability. Iodine(III) and iodine(V) derivatives are now routinely used in organic synthesis as reagents for various selective oxidative transformations of complex organic molecules. Several areas of hypervalent organoiodine chemistry have recently attracted especially active interest and research activity. These areas, in particular, include the synthetic applications of 2-iodoxybenzoic acid (IBX) and similar oxidizing reagents based on the iodine(V) derivatives, the development and synthetic use of polymer-supported and recyclable polyvalent iodine reagents, the catalytic applications of organoiodine compounds, and structural studies of complexes and supramolecular assemblies of polyvalent iodine compounds.

The chemistry of polyvalent iodine has previously been covered in four books1–4 and several comprehensive review papers.5–17 Numerous reviews on specific classes of polyvalent iodine compounds and their synthetic applications have recently been published.18–61 Most notable are the specialized reviews on [hydroxy(tosyloxy)iodo]benzene,41 the chemistry and synthetic applications of iodonium salts,29,36,38,42,43,46,47,54,55 the chemistry of iodonium ylides,56–58 the chemistry of iminoiodanes,28 hypervalent iodine fluorides,27 electrophilic perfluoroalkylations,44 perfluoroorgano hypervalent iodine compounds,61 the chemistry of benziodoxoles,24,45 polymer-supported hypervalent iodine reagents,30 hypervalent iodine-mediated ring contraction reactions,21 application of hypervalent iodine in the synthesis of heterocycles,25,40 application of hypervalent iodine in the oxidation of phenolic compounds,32,34,50–53,60 oxidation of carbonyl compounds with organohypervalent iodine reagents,37 application of hypervalent iodine in (hetero)biaryl coupling reactions,31 phosphorolytic reactivity of o-iodosylcarboxylates,33 coordination of hypervalent iodine,19 transition metal catalyzed reactions of hypervalent iodine compounds,18 radical reactions of hypervalent iodine,35,39 stereoselective reactions of hypervalent iodine electrophiles,48 catalytic applications of organoiodine compounds,20,49 and synthetic applications of pentavalent iodine reagents.22,23,26,59

The main purpose of the present review is to summarize the data that appeared in the literature following publication of our previous reviews in 1996 and 2002. In addition, a brief introductory discussion of the most important earlier works is provided in each section. The review is organized according to the classes of organic polyvalent iodine compounds with emphasis on their synthetic application. Literature coverage is through July 2008.

Chemistry of Polyvalent Iodine

The preparation, structure, and chemistry of hypervalent iodine compounds are reviewed with emphasis on their synthetic application. Compounds of iodine possess reactivity similar to that of transition metals, but have the advantage of environmental sustainability and efficient utilization of natural resources. These compounds are widely used in organic synthesis as selective oxidants and environmentally friendly reagents. Synthetic uses of hypervalent iodine reagents in halogenation reactions, various oxidations, rearrangements, aminations, C–C bond-forming reactions, and transition metal-catalyzed reactions are summarized and discussed. Recent discovery of hypervalent catalytic systems and recyclable reagents, and the development of new enantioselective reactions using chiral hypervalent iodine compounds represent a particularly important achievement in the field of hypervalent iodine chemistry. One of the goals of this Review is to attract the attention of the scientific community as to the benefits of...

Advances in Synthetic Applications of Hypervalent Iodine Compounds

Alan Ford,† Hugues Miel, Aoife Ring,† Catherine N. Slattery,† Anita R. Maguire,*,†,‡ and M. Anthony McKervey* †Department of Chemistry and ‡School of Pharmacy, Analytical and Biological Chemistry Research Facility, Synthesis and Solid State Pharmaceutical Centre, University College Cork, Cork, Ireland Almac Discovery Ltd., David Keir Building, Stranmillis Road, Belfast BT9 5AG, United Kingdom Almac Sciences Ltd., Almac House, 20 Seagoe Industrial Estate, Craigavon BT63 5QD, United Kingdom

Modern Organic Synthesis with α-Diazocarbonyl Compounds

2.3. [4 + 4] Cycloadditions 1058 2.4. Photocycloadditions of Aromatic Compounds 1058 2.4.1. Benzene Derivatives 1058 2.4.2. Condensed Aromatic Compounds 1060 3. Photochemical Rearrangements 1061 4. Cyclizations 1064 4.1. Pericyclizations 1064 4.2. Norrish−Yang Reaction 1066 5. Photochemical Extrusion of Small Molecules 1067 6. Photochemical Electron Transfer 1068 6.1. Photochemical Electron-Transfer Reactions with a Catalytic Sensitizer 1068

Photochemical Reactions as Key Steps in Organic Synthesis

10. Patented Literature 2616 10.1. Esterification 2616 10.2. Ether Formation 2619 10.2.1. Etherification without Cyclization 2619 10.2.2. Etherification with Cyclization 2624 10.3. N-Alkylation 2625 10.4. Other Reactions 2627 11. Summary and Outlook 2628 12. Note Added in Proof 2628 13. Abbreviations Used in This Review 2629 14. Acknowledgments 2629 15. Supporting Information Available 2630 16. References 2630

Mitsunobu and Related Reactions: Advances and Applications

Enantiodifferentiating tetrahydrofuranylation of but-3-enyl carboxylates using optically active hypervalent iodine(III) reagents via a 1,3-dioxan-2-yl cation intermediate

Activation-temperature dependence in enantioselective hydrogenation of unsaturated carboxylic acids over cinchonidine-modified Pd/C catalysts

Structural requirements for substrate in highly enantioselective hydrogenation over the cinchonidine-modified Pd/C

An enantiomeric ratio of 10:1 (82% ee) was achieved for the first time in the hydrogenation of α,β-unsaturated acids with heterogeneous catalysts by designing the substrate structure to enhance the interaction with the catalyst, and to increase the intrinsic stereoselectivity.

The effect of the substrate structure on the stereoselectivity in an asymmetric hydrogenation of unsaturated carboxylic acids over cinchonidine-modified palladium catalyst

Tadashi Okuyama

Papers

Enantiodifferentiating tetrahydrofuranylation of but-3-enyl carboxylates using optically active hypervalent iodine(III) reagents via a 1,3-dioxan-2-yl cation intermediate

Activation-temperature dependence in enantioselective hydrogenation of unsaturated carboxylic acids over cinchonidine-modified Pd/C catalysts

Structural requirements for substrate in highly enantioselective hydrogenation over the cinchonidine-modified Pd/C

The effect of the substrate structure on the stereoselectivity in an asymmetric hydrogenation of unsaturated carboxylic acids over cinchonidine-modified palladium catalyst

Argentation Equilibria of Substituted Styrenes