Recent Advances of ChiraI Spiro Ligands and Their Catalysts in Asymmetric Catalysis

Metal-catalyzed asymmetric reaction are one of the important approaches to provide optically active compounds. The design and synthesis of novel chiral ligands has been a key and challenging topic in the field of asymmetric catalysis. Since the late 1990s, Spiro skeleton was introduced to chiral ligands by chemists, then series of Spiro monodentate or multidentate ligand contaning spim [4.4] nonane, spirobiindane, spiro [4.4] nonadiene and spiroketal skeletons were developed and successfully applied in asymmetric catalytic hydrogenation, asymmetric carbon-carbon bonds forming reaction or carbon-heteroatom bond forming reaction, creating many valuable enantiomerically pure products. The development of spiro ligand and their catalyst strongly promote the industry applications for asymmetric catalytic reaction.