Electrophilic Trifluoromethylation by Use of Hypervalent Iodine Reagents

Abstract

Introduction 650 2. Synthesis 651 3. Structure and Properties 653 3.1.Reagents 1 and 2 653 3.2.Further Reagents 653 4. Activation 654 4.1.Activation by Lewis Acids 654 4.2.Activation by Brønsted Acids 655 4.2.1.Sulfonic Acids 655 4.2.2.Protonated Reagent 2: Frontier Molecular Orbital Considerations 656 4.2.3.Trifluoromethylation of S-Hydrogen Phosphorothioates and Hydrogen Phosphates 657 4.3.Activation by Metals and Radical Trifluoromethylation 657 4.3.1.Rhenium-Catalyzed Trifluoromethylation of Arenes 657 4.3.2.Copper-Catalyzed Trifluoromethylation 658 4.3.3.Palladium-Mediated Trifluoromethylation 658 4.3.4.Trifluoromethylation of Thiols 658 5. Applications 659 5.1.Trifluoromethylation of Non-Carbon-Centered Nucleophiles 659 5.1.1.Sulfur-Centered Nucleophiles 659 5.1.2.Phosphorus-Centered Nucleophiles 660 5.1.3.Oxygen-Centered Nucleophiles 662 5.1.4.Nitrogen-Centered Nucleophiles 663 5.2.Trifluoromethylation of Carbon-Centered Nucleophiles 664 5.2.1.Carbonyl Compounds 664 5.2.2.Hydrazones 666 5.2.3.Aryl and Heteroaryl Compounds 666 5.2.4.Terminal Alkynes 668 5.2.5.Vinylic Functionalization 669 5.2.6.Quinones 670 5.2.7.Allylic Functionalization 670 5.2.8.Additions Involving External Nucleophiles 671 5.2.9.Heterocyclizations 673 5.2.10.Carbocyclizations 675 5.2.11.Rearrangements 676 6.In Situ Formation of [ArICF 3 ] + 678 7. Conclusions