Cyclic diaryliodonium salts: applications and overview

Owing to the recent renewed interest and groundbreaking advances in hypervalent chemistry, cyclic diaryliodonium salts have had a myriad of unique applications in the past decade. Their numerous properties, such as an efficient dual arylation mechanism, straightforward one-pot synthesis compatibility, wide substrate scope, and functionalization tolerance, have made them appropriate starting materials for many bioactive compounds. Fluorenes, thiophenes, carbazoles, phenanthrenes, and many other useful cyclic bioactive molecules that are essential for pharmaceutical synthesis can be readily accessed from cyclic diaryliodonium salts. Particular focus has been given to the high optical activity and good enantiomeric excess of the products that facilitate the easy formation of many difficult-to-obtain optical isomers, such as atropisomers. This review aims to compile and summarize all the recent advances in synthesizing methodologies to prepare the important compounds where cyclic diaryliodonium salt is an integral part of the methodologies and would hopefully provide a good foundation for further research on this topic.