Single-chain chiral Ru-Cu star polymers for highly efficient catalytic aqueous asymmetric transfer hydrogenation

Abstract

It is of great research value to design simulated enzyme catalysts with high catalytic activity, high selectivity and that are reusable in water. In this work, a star-shaped thermal responsive polymer-Ru/diamine functional intelligent chiral catalyst was synthesized by controlled atom transfer radical polymerization (ATRP). Polymerization can be controlled through self-catalysis of chiral monomers and polymers. Because of the complex that forms between the chiral polymer and Cu2+, the synthesized star polymer experiences a chiral amplification effect. At the same time, the star Ru-Cu catalyst can be assembled into single-chain polymers in water, which showed better catalytic activity and selectivity than the Ru catalyst for aqueous asymmetric reactions, and can be recycled up to six times. Our work provides a new method for controllable synthesis of chiral polymers without additional ligands and the need to remove Cu2+ at the end of the reaction, making the method green and more cost-effective. In summary, bimetallic nanocatalysts were controllably constructed by star chiral polymers through the ATRP pathway. This method significantly aids the development of helical chiral polymers and the preparation of high-efficiency enzyme catalysts.