Zwitterionic Iodonium Compounds: Useful Tools in Organic Synthesis

Abstract

Zwitterionic iodonium compounds, ZICs, a major class of hypervalent iodine compounds, are flexible units that offer access to interesting structures. This Account focuses on the synthetic applications of iodonium phenolates, ylides of hydroxycoumarins and, mainly, ylides of hydroxyquinones.

Transition-Metal-Free C-Diarylations to Reach All-Carbon Quaternary Centers

“…Aryliodonium ylides are special types of iodine(III) reagents that are generally formed from dicarbonyl compounds. Such reagents have been used in C -functionalizations via, e.g., fluorination, trifluoromethylation, cycloaddition reactions, and as carbene precursors in metal-catalyzed reactions. − Zwitterionic iodonium compounds with a phenoxy moiety are a related compound class that can undergo intramolecular aryl transfer to form diaryl ethers. − The utility of such reagents in diarylations to transfer both aryls of the reagent remains unexplored. To our delight, reactions with zwitterionic reagent 5 smoothly delivered the corresponding diarylated malonates 6a – 6c decorated with two different handles for further functionalization (Scheme D).…”