Hypervalent Iodine Chemistry

1 Introduction and General Overview of Polyvalent Iodine Compounds 1

1.1 Introduction 1

1.2 Classification and Nomenclature of Polyvalent Iodine Compounds 3

1.3 Hypervalent Bonding 4

1.4 General Structural Features 8

1.4.1 Experimental Structural Studies 9

1.4.2 Computational Studies 11

1.5 General Principles of Reactivity 12

1.5.1 Ligand Exchange and Reductive Elimination 13

1.5.2 Radical Reactions 14

1.5.3 Single-Electron Transfer (SET) Reactions 15

References 15

2 Preparation, Structure, and Properties of Polyvalent Iodine Compounds 21

2.1 Iodine(III) Compounds 21

2.1.1 Inorganic Iodine(III) Derivatives 21

2.1.2 Organoiodine(III) Fluorides 23

2.1.3 Organoiodine(III) Chlorides 27

2.1.4 Organo-Iodosyl Compounds 31

2.1.5 Organoiodine(III) Carboxylates 35

2.1.6 [Hydroxy(Organosulfonyloxy)Iodo]Arenes 43

2.1.7 Organoiodine(III) Derivatives of Strong Acids 48

2.1.8 Iodine(III) Heterocycles 50

2.1.9 Iodonium Salts 76

2.1.10 Iodonium Ylides 99

2.1.11 Iodine(III) Species with Three Carbon Ligands 107

2.1.12 Iodine(III) Species with I-N Bonds 107

2.2 Iodine(V) Compounds 114

2.2.1 Inorganic Iodine(V) Derivatives 114

2.2.2 Noncyclic and Pseudocyclic Iodylarenes 115

2.2.3 Iodine(V) Heterocycles 120

2.2.4 Organoiodine(V) Fluorides 126

2.3 Iodine(VII) Compounds 127

References 128

3 Hypervalent Iodine Reagents in Organic Synthesis 145

3.1 Reactions of Iodine(III) Compounds 145

3.1.1 Fluorinations 146

3.1.2 Chlorinations 152

3.1.3 Brominations 158

3.1.4 Iodinations 160

3.1.5 Oxidation of Alcohols 164

3.1.6 Oxidative Functionalization of Carbonyl Compounds 168

3.1.7 Oxidative Functionalization of Silyl Enol Ethers 171

3.1.8 Oxidation of Alkenes and Alkynes 173

3.1.9 Oxidations at the Benzylic or Allylic Position 181

3.1.10 Oxidative Functionalization of Aromatic Compounds 182

3.1.11 Oxidative Dearomatization of Phenols and Related Substrates 183

3.1.12 Oxidative Coupling of Aromatic Substrates 196

3.1.13 Oxidative Cationic Cyclizations, Rearrangements, and Fragmentations 201

3.1.14 Oxidations at Nitrogen, Sulfur, and other Heteroatoms 216

3.1.15 Azidations 222

3.1.16 Aminations 230

3.1.17 Thiocyanations and Arylselenations 232

3.1.18 Radical Fragmentations, Rearrangements, and Cyclizations 236

3.1.19 Reactions via Alkyliodine(III) Intermediates 248

3.1.20 Transition Metal Catalyzed Oxidations 250

3.1.21 Transition Metal Catalyzed Aziridinations and Amidations 253

3.1.22 Reactions of Iodonium Salts and C-Substituted Benziodoxoles 260

3.1.23 Reactions of Iodonium Ylides 278

3.2 Synthetic Applications of Iodine(V) Compounds 282

3.2.1 Noncyclic and Pseudocyclic Iodylarenes 283

3.2.2 2-Iodoxybenzoic Acid (IBX) 288

3.2.3 Dess-Martin Periodinane (DMP) 296

3.2.4 Inorganic Iodine(V) Reagents 302

3.3 Synthetic Applications of Iodine(VII) Compounds 303

References 307

4 Hypervalent Iodine Catalysis 337

4.1 Catalytic Cycles Based on Iodine(III) Species 337

4.1.1 Oxidative Functionalization of Carbonyl Compounds 338

4.1.2 Oxidative Functionalization of Alkenes and Alkynes 342

4.1.3 Oxidative Bromination of Aromatic Compounds 346

4.1.4 Oxidative Amination of Aromatic Compounds 347

4.1.5 Oxidation of Phenolic Substrates to Quinones and Quinols 349

4.1.6 Oxidative Spirocyclization of Aromatic Substrates 350

4.1.7 Carbon-Carbon Bond-Forming Reactions 354

4.1.8 Hofmann Rearrangement of Carboxamides 355

4.1.9 Oxidation of Anilines 357

4.2 Catalytic Cycles Based on Iodine(V) Species 358

4.3 Tandem Catalytic Systems Involving Hypervalent Iodine and other Co-catalysts 364

4.4 Catalytic Cycles Involving Iodide Anion or Elemental Iodine as Pre-catalysts 368

References 377

5 Recyclable Hypervalent Iodine Reagents 381

5.1 Polymer-Supported Iodine(III) Reagents 381

5.2 Polymer-Supported Iodine(V) Reagents 389

5.3 Recyclable Nonpolymeric Hypervalent Iodine(III) Reagents 391

5.3.1 Recyclable Iodine(III) Reagents with Insoluble Reduced Form 393

5.3.2 Recovery of the Reduced Form of a Hypervalent Iodine Reagent Using Ion-Exchange Resins 397

5.3.3 Ionic-Liquid-Supported Recyclable Hypervalent Iodine(III) Reagents 400

5.3.4 Magnetic Nanoparticle-Supported Recyclable Hypervalent Iodine(III) Reagent 401

5.3.5 Fluorous Recyclable Hypervalent Iodine(III) Reagents 402

5.4 Recyclable Nonpolymeric Hypervalent Iodine(V) Reagents 405

5.5 Recyclable Iodine Catalytic Systems 406

References 409

6 Reactions of Hypervalent Iodine Reagents in Green Solvents and under Solvent-Free Conditions 413

6.1 Reactions of Hypervalent Iodine Reagents in Water 413

6.2 Reactions of Hypervalent Iodine Reagents in Recyclable Organic Solvents 418

6.3 Reactions of Hypervalent Iodine Reagents under Solvent-Free Conditions 420

References 422

7 Practical Applications of Polyvalent Iodine Compounds 425

7.1 Applications of Inorganic Polyvalent Iodine Derivatives 425

7.2 Applications of Hypervalent Iodine(III) Compounds as Polymerization Initiators 426

7.3 Application of Iodonium Salts for Fluoridation in Positron Emission Tomography (PET) 431

7.4 Biological Activity of Polyvalent Iodine Compounds 440

References 443

Index