A membrane-mediated modulation for chemoenzymatic redox deracemization of secondary alcohols and applications

The exploration of a chemoenzymatic dual catalysis system can bridge the methodological gap between chemical and biological catalysis under mild reaction conditions for the preparation of chiral molecules. Herein, we developed a membrane-mediated approach to integrate incompatible chemo-oxidation and biotransformation processes into a single operation in a sustainable catalysis process. The designed chemoenzymatic dual catalysis efficiently converts racemic secondary alcohols into chiral alcohols and amines through environmentally friendly sequential transformations. Orthogonal experiments demonstrate that sodium anthraquinone-2-sulfonate or 2-iodoxybenzoic acid, located in a compartment, catalyzes the oxidation of racemic alcohols to ketones, while alcohol or amine dehydrogenase in another compartment converts the in situ-generated ketones to chiral alcohols or amines. The comparative reaction investigations reveal that the membrane-mediated chemoenzymatic dual catalysis offers a technical solution to resolve incompatibilities caused by intrinsic mutual deactivation and extrinsic reaction conditions. Kinetic studies and control experiments disclose a collaborative catalysis process consisting of initial chemo-oxidation followed by subsequent biotransformation, affording the corresponding chiral secondary alcohols or secondary amines with high yields and excellent enantioselectivities. A membrane-mediated modulation used for the chemoenzymatic dual catalysis of secondary alcohols is established. This combined catalytic system creates two independent compartments to enable a collaborative chemo-oxidation and biotransformation process in a tandem mode, providing a wide range of chiral alcohol and amine products with improved yields and enantioselectivities.