Cobalt‐Catalyzed Regio‐, Diastereo‐ and Enantioselective Intermolecular Hydrosilylation of 1,3‐Dienes with Prochiral Silanes

The incorporation of silicon and synthesis of organosilicon small molecules provide unique opportunities for medicinal applications. The biological investigation of organosilicon small molecules is particularly interesting because of differences in their chemical properties that can contribute to enhanced potency and improved pharmacological attributes. Applications such as inhibitor design, imaging, drug release technology, and mapping inhibitor binding are discussed.

Enzymes that catalyze carbon-silicon bond formation are unknown in nature, despite the natural abundance of both elements. Such enzymes would expand the catalytic repertoire of biology, enabling living systems to access chemical space previously only open to synthetic chemistry. We have discovered that heme proteins catalyze the formation of organosilicon compounds under physiological conditions via carbene insertion into silicon-hydrogen bonds. The reaction proceeds both in vitro and in vivo, accommodating a broad range of substrates with high chemo- and enantioselectivity. Using directed evolution, we enhanced the catalytic function of cytochrome c from Rhodothermus marinus to achieve more than 15-fold higher turnover than state-of-the-art synthetic catalysts. This carbon-silicon bond-forming biocatalyst offers an environmentally friendly and highly efficient route to producing enantiopure organosilicon molecules.