A Radical-Based, Transition Metal-Free Approach for Diaryl Ketone Synthesis.

Diaryl ketones represent a pivotal class of compounds, widely used in pharmaceuticals, agrochemicals, and materials science. Driven by the urgent need for safer and more sustainable synthetic methodologies, developing innovative approaches in this area has become a critical priority for both academia and industry. In this context, a straightforward yet novel one-pot strategy for synthesizing a broad array of diaryl ketones, including valuable target molecules, is presented. This approach diverges from conventional methods by employing a radical process, in which aryl halides react with benzonitriles in a basic medium, relying exclusively on the organic reductant pair KOtBu/DMA and air as the oxidant. Mechanistic studies suggest that the KOtBu/DMA system triggers the generation of aryl radicals, thereby initiating the process. This method stands out by overcoming key limitations of conventional approaches, notably avoiding corrosive reagents, toxic or expensive catalysts, peroxides, and hazardous carbon monoxide, thus aligning with the shift toward safer, more sustainable alternative synthetic strategies.