Main-Chain Ionic Chiral Polymers: Synthesis of Optically Active Quaternary Ammonium Sulfonate Polymers and Their Application in Asymmetric Catalysis

摘要

Recently, polymer-immobilized asymmetric catalysts have at-ntracted considerable attention. Although substantial research per-ntaining to the use of side-chain-functionalized polymers has beenncarried out, only a limited number of investigations to elucidatenthe use of main-chain-functionalized polymers have been performed.nSome examples of main-chain-functionalized polymers includenpolymeric chiral salen ligand,n1npoly(amino acid),n2npoly(tartrate),n3npolybinaphthols,n4nand helical polymers.n5nThese main-chain chiralnpolymers have been successfully used as chiral catalysts in variousnkinds of asymmetric reactions. The rigid and sterically regularnpolymer catalysts may have a better defined microenvironment atnthe catalytic sites and have allowed systematic modification of theirncatalytic properties.