Broadening the scope of biocatalytic C–C bond formation

Enzymes exercise impeccable control over chemoselectivity, site selectivity and stereoselectivity in reactions they mediate, such that we have witnessed a surge in the development of new biocatalytic methods. Although carbon–carbon (C–C) bonds are the central framework of organic molecules, biocatalytic methods for their formation have largely been limited to a select few lyase enzymes. Thus, despite several decades of research, there are not many biocatalytic C–C-bond-forming transformations at our disposal. This Review describes the suite of enzymes available for highly selective, biocatalytic C–C bond formation. We discuss each class of enzyme in terms of native activity, alteration of this activity through protein or substrate engineering, and its utility in abiotic synthesis. Discovery and application of enzymes that catalyse new reactions is essential for broad implementation of biocatalysts in organic synthesis. This Review describes recent developments in biocatalytic carbon–carbon bond formation.