Cyclic Diaryliodonium Salts: Eco‐Friendly and Versatile Building Blocks for Organic Synthesis

Abstract

Cyclic diaryliodoniums are an important class of high‐valent aromatic iodine reagents for the synthesis of various axially chiral biaryls and biaryl compounds. Moreover, transition‐metal‐catalyzed annulation has been established for the construction of various heterocyclic rings and ladder‐type π‐conjugated polycyclic aromatic hydrocarbons with readily available cyclic diaryliodoniums as the starting materials. As halogen‐bonding donors, cyclic aryliodoniums have been explored as organocatalysts in a variety of organic reactions. In this review, the application progress of cyclic diaryliodoniums has been systematically outlined, which highlights recent developments in the application reactions of cyclic diaryliodoniums, including synthetic application, limitations and reaction mechanisms in representative cascade reactions to provide insights for the development prospects of cyclic diaryliodoniums.

Cyclic diaryliodonium salts: applications and overview

“…Most cyclic diaryliodonium salts are known as effective, mild, environment-friendly double arylating agents of various nucleophiles, but nowadays, the applications are broad and diversified, which make the cyclic iodonium salts a unique and important reagent in the synthetic chemistry field. 5 Most reactions of cyclic diaryliodonium salts proceed in a one-step, one-pot fashion, and atom-economical manner, whereas acyclic diaryliodonium salts give aryl iodide as a waste product, which is not observed in the cyclic diaryliodonium salts. The cyclic diaryliodonium salts are prominent and highly usable in the synthesis of organic compounds, such as optically active isomers, bioactive axially chiral biaryls, helicenes, 6,7 polycyclic aromatic hydrocarbons (PAHs), polycyclic azepine, and polycyclic heterocyclics.…”

“…Through Pd(II) bis(acetylacetonate) and widely accessible cyclic diaryliodonium salt 4, Wang and his colleagues 63 devised a highly efficient technique for the simple one-step manufacturing of single and double [4]-carbohelicenes 28 as well as [4,5,4]-fused triple carbohelicenes 30. The authors carried out the reaction utilizing cyclic diaryliodonium salt 4, followed by regioselective C8-H bond activation and repeated C-H arylations of naphthamides 27 (Scheme 15).…”

Oxidative cyclization and enzyme-free deiodination of thyroid hormones

“…We found such a potential pathway by serendipity as part of an ongoing research program that is intended to elaborate and understand a potential biologically relevant non-enzymatic oxidation of thyroxines to hypervalent iodine reagents ox-T3/T4 or cyclic iodaoxinium salts 1 (cyclo-ox-T3/T4) derived from them (Scheme 2). [13][14][15][16][17][18] In the future these substrates could also enable diverse further derivations based on previous work by Chen and co-workers. 19,20…”

Distal iodine migration of arylalkynes via cyclic monoaryliodonium salts

“…Cyclic diaryliodonium salts (CDAIs) have received significant attention from the synthetic chemistry community in the past few years. 1 These CDAIs could be used as effective mono-arylative reagents for the synthesis of biaryl atropisomers by an enantioselective ring-opening strategy. 2 Besides, CDAIs have been employed as atom-economic di-arylative reagents in tandem reactions for producing a wide range of important carbocyclic and heterocyclic motifs with high chemical complexity.…”