| Obtaining optically pure chiral compounds has become an important goal in some industries,which kinetic resolution is a commonly used method,but the classical kinetic resolution method itself has great defects,splitting optical enantiomers.The theoretical yield is only 50%.The dynamic kinetic resolution developed in recent years can overcome the above disadvantages,which can completely convert the substrate into an optical enantiomer with a single configuration,and the theoretical yield can reach 100%.The method of dynamic kinetic resolution-asymmetric hydrogen transfer catalyzed by ruthenium has been widely reported at home and abroad,and it has high research value.Based on this we hope to apply the dynamic mechanical resolution-asymmetric hydrogen transfer method to our experiments.γ-butyrolactone are important class of organic molecules.In recent years,reports on them have been increasing at home and abroad.This also promotes the development ofγ-butyrolactone due to its very wide application and research value.It can be applied to the following aspects,such as fuel additives,flavors and flavors,resistance to rice peony,and anti-tumor drugs.At present,there are few reports on the chiralγ-butyrolactone obtained by the racemic raw materials.Therefore,we have synthesized two chiral centersγ-butyrolactone by asymmetric hydrogen transfer from the racemic starting materials.In the second chapter,we used a chiral ruthenium-catalyzed dynamic kinetic resolution-asymmetric hydrogen transfer cyclization tandem method in a mixed solvent of DCE/H2O（v/v,3/1）at 60°C.Using HCOONa as a hydrogen source,providing a variety of chiral ethyl 3,4-dihydro-2H-pyran-5-carboxylates in high yields（up to 93%）with excellent enantioselectivities（up to 98%）and diastereoselectivities（up to 99:1 dr）.This method has the advantages of simple operation,mild reaction conditions and high yields.In the third chapter,we synthesized a series of ethyl 2-oxo-5-phenyltetrahyrdofu ran-3-carboxylates and ethyl 2-amino-5-phenyl-4,5-dihydrofuran-3-carboxylates by the method of asymmetric hydrogen transfer in DCM at 40°C using HCOOH:Et3N（5:2）as a hydrogen source with good yields（up to 97%）.Among the products,a product with excellent enantioselectivities（up to 96%）and diastereoselectivities（up to 99:1 dr）,and another product with excellent enantioselect--ivities（up to 96%）.The structure of the products was characterized by 1H-NMR,13C-NMR,HRMS and the enantioselectivity of the product was determined by HPLC. |
