The coupling reactions are essential tools in organic synthesis, enabling the formation of crucial chemical bonds in pharmaceuticals, agrochemicals, and advanced materials. However, these traditional methods have long relied on environmentally taxing transition metal catalysts, such as palladium, which are often scarce, costly, and generate unwanted byproducts.
- These limitations have prompted researchers to seek alternative strategies that better align with the principles of green and sustainable chemistry (GSC).
- The goals of these alternatives include minimizing waste, reducing reliance on rare metals, and lowering energy consumption, all while maintaining high efficiency and selectivity.
“Coupling reactions are among the most transformative tools in organic chemistry, enabling the formation of crucial chemical bonds in pharmaceuticals, agrochemicals, and advanced materials. Dohi.
The hypervalent iodine approach leverages the unique properties of diaryliodonium salts, which serve as highly reactive intermediates in coupling reactions. By strategically manipulating the oxidation state of iodine atoms, researchers have been able to generate aryl cation-like species, radicals, and aryne precursors that facilitate selective bond formation.
- Broad substrate scope and high functional group tolerance, making it particularly attractive for applications in medicinal chemistry.
- Reduces reliance on costly catalysts while also enhancing the atom economy of coupling processes.
- Enables the efficient synthesis of diverse molecular architectures and the recycling of aryl iodide byproducts.
- Base-promoted aryl-iodide dissociation
- Photoinduced activation
- Electrochemical activation
- Electrophotochemical activation
By compiling and analyzing recent advances, the authors wish to guide and inspire further research in this area. “We hope that this review will be of interest to researchers aiming to develop new methods of solving the problems associated with this field of chemistry,” says Prof. Kita.
These methods have the potential to reshape the future of organic chemistry by reducing environmental impact and lowering production costs. By minimizing waste, reducing reliance on rare metals, and lowering energy consumption, these methods may play a critical role in the long-term development of pharmaceuticals and other fine chemicals.
As the field continues to evolve, the present contributions will hopefully serve as a foundation for future breakthroughs in sustainable chemistry.
