Recent Advances in Asymmetric Phase-Transfer Catalysis

摘要

The use of chiral nonracemic onium salts and crown ethers as effective phase-transfer catalysts have been studied intensively primarily for enantioselective carbon-carbon or carbon-heteroatom bond-forming reactions under mild biphasic conditions.An essential issue for optimal asymmetric catalysis is the rational design of catalysts for targeted reaction,which allows generation of a well-defined chiral ion pair that reacts with electrophiles in a highly efficient and stereoselective manner.This concept,together with the synthetic versatility of phase-transfer catalysis,provides a reliable and general strategy for the practical asymmetric synthesis of highly valuable organic compounds.