Chemical and biocatalysis in one pot

Surfactants make it possible to perform chemical catalysis and biocatalysis in the same aqueous solution (Nat. Commun. 2019, DOI: 10.1038/s41467-019-09751-4). Bruce Lipshutz of the University of California, Santa Barbara, and colleagues used vitamin E–based surfactants to form micelles in water that have a hydrophobic interior, a technique they and others have been exploring for some time. Lipshutz’s group has now demonstrated a palladium-catalyzed Sonogashira cross coupling of acetoaryl starting molecules, which happens inside the micelle, followed by reduction of the resulting ketone using alcohol dehydrogenase enzymes. The researchers adjusted the temperature, concentration, and pH of the solution before adding the enzymes. They also demonstrated other cross-coupling reactions. In addition to showing that micelles can mediate these one-pot transformations, the group found that they also appear to speed up rates of various reactions. Lipshutz explains that water-insoluble reactants and products can clog the entrance to an enzyme’s binding pocket, and he says that micelles can act like filters and lower the concentration of these molecules.