Enantioselective One-Pot Synthesis of Biaryl-Substituted Amines by Combining Palladium and Enzyme Catalysis in Deep Eutectic Solvents

The first application of <i>Deep Eutectic Solvents</i> (<i>DESs</i>) in asymmetric bioamination of ketones has been accomplished. The amine transaminases (ATAs) turned out to be particularly stable in <i>DES</i>-buffer mixtures at a percentage of up to 75% (w/w) neoteric solvent. Moreover, this reaction medium was used to perform a chemoenzymatic cascade toward biaryl amines by coupling a Suzuki reaction sequentially with an enantioselective bioamination catalyzed by the recently discovered ATA from <i>Exophiala xenobiotica</i> (EX-ωTA). The solubilizing properties of <i>DESs</i> enabled the metal-catalyzed step at 200 mM loading of substrate and the subsequent biotransformation at 25 mM.