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

The first application of Deep Eutectic Solvents (DESs) in asymmetric bioamination of ketones has been accomplished. The amine transaminases (ATAs) turned out to be particularly stable in DES-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 Exophiala xenobiotica (EX-ωTA). The solubilizing properties of DESs enabled the metal-catalyzed step at 200 mM loading of substrate and the subsequent biotransformation at 25 mM.