Toshifumi Dohi
Ritsumeikan University, Japan
Title: New conceptual diary liodonium salts for metal-free arylation of carboxylic acids and other coupling reactions
Biography
Biography: Toshifumi Dohi
Abstract
Diaryliodonium salts are used in organic synthesis as versatile arylating agents and for other many applications. However, the methods utilizing these salts in synthesis still have limitations, such as the requirements of base, and sometimes accompanied problems in the product yields and aryl selectivities for low nucleophilic compounds and the salts having two different aryl groups. Herein, we have developed a more efficient arylation of carboxylic acids meeting green chemistry by utilizing new conceptual diaryliodonium salts. By utilizing the newly designed salts 1, the efficient metal-free arylations of carboxylic acids occur upon heating without base and solvent, giving aryl esters in extremely high yields in short reaction times. In comparison, the reactions are more efficient, especially for low nucleophilic carboxylic acids, such as p-nitrobenzoic acid, that were unsatisfactory as substrates in known intermolecular coupling methods using ordinary diaryliodonium salts. In addition, the arylations usually proceeded with perfect chemoselectivities even in the presense of other nucleophilic groups. It is known that diaryliodonium salts show unique reactivities for other metal-free arylating reactions depending on the nature of the ligands. The summary of developments in our laboratory is presented together with the recent research study.
