New procedure will reduce the need for rare metals in chemical synthesis

Pharmaceuticals, plastics, and many other chemical products have transformed human life. To prepare these products, chemists often use a catalyst—frequently based on rare metals—at various points in their syntheses. Although rare-metal catalysts are incredibly useful, their limited supply means that their use is unsustainable in the long term. Synthetic chemists need an alternative.

In a study recently published in Angewandte Chemie, researchers from Kanazawa University report such an alternative. Their research on a broad class of chemical reactions that are common in pharmaceutical and other syntheses will pave the way to a more sustainable chemical industry.

The 2010 Nobel Prize in Chemistry went to researchers who used catalysts based on palladium metal to perform a common type of chemical reaction known as cross-coupling. Such catalysts work very well for synthesizing what are known as congested quaternary carbon centers, which are common in molecules used in agriculture and medicine. However, for long-term sustainability, researchers need an alternative to rare-metal catalysts.

"We used benzylic organoborates to perform tertiary alkylative cross-coupling of aryl or alkyl electrophiles," says Hirohisa Ohmiya, corresponding author of the study. "Our procedure does not use rare elements and is a straightforward route to quaternary carbon centers."