Novel Approach for Aromatic Cluster Integration

Researchers at The University of Osaka have developed a novel synthetic method that allows boron-rich carborane clusters to be incorporated into aromatic compounds simply by 'mixing and heating.' 

The new approach removes the need for the complex and hazardous procedures that have historically limited the practical use of carborane chemistry. The study was published in the Journal of the American Chemical Society.

Carboranes are icosahedral clusters of boron and carbon atoms, valued for their unique three-dimensional aromaticity, exceptional stability, and neutron-capturing ability. These features make them highly attractive for applications in boron neutron capture therapy (BNCT), functional materials, and drug design.

Previously, incorporating carboranes into aromatic frameworks involved complex, multi-step reactions under harsh conditions, achievable only by highly specialized chemists.

A research team led by Dr. Yoichi Hoshimoto has successfully synthesized a stable reagent, lithium bis(ortho-carboranyl) cuprate (Li/Cu-1). Using this reagent, aromatic compounds can be converted into carborane-containing molecules through a simple 'dump-and-stir' process involving just mixing and heating.

This method allows large-scale, high-yield production from inexpensive aryl bromides and chlorides, eliminating the need for hazardous reagents and low-temperature operations. It's a significant step forward in expanding the practical applications of carborane chemistry in medicine, materials science, and sustainable manufacturing.

We believe this simple approach will empower many more scientists to explore the field of carborane chemistry. With this achievement, an instant synthesis method for carborane-containing molecules, one that could reshape the future, has been realized.

Dr. Yoichi Hoshimoto, Study Corresponding Author, The University of Osaka

Journal Reference:

Hisata, Y., et al. (2025) An Isolated Lithium ortho-Carboranyl Cuprate Complex for the Synthesis of Multiple-Carborane-Substituted Arenes from (Hetero)Aryl Bromides and Chlorides. Journal of the American Chemical Society. doi.org/10.1021/jacs.5c13004.