The Synthesis Of A Novel Chiral Schiff Base Block Copolymer And Its Catalytic Asymmetric Henry Reaction

The asymmetric Henry reaction is still one of the most intensively studied asymmetric reactions.It can form one or two new stereocenters with forming C-C bond.The ?-nitroalcohol,a product of the Henry reaction,is most important chemical intermediate which can be easily converted to other useful intermediate compounds.Therefore,Henry reaction has important application value in the synthesis of pharmaceuticals and natural products.With the full recognition of important functions of chiral compounds,chiral catalyzed asymmetrical Henry reaction becomes sustained hot topic for chemists.Camphor is one of most cheap and readily available natural chiral materials,which has unique spatial stereostructure.But,a few modification positions were stronger limited it's application in asymmetrical reaction.Our group devoted to study the synthesis and application of new chiral camphor derivatives.Some of important results already published.Immobilization is important method to get the recovery and reuse of homogeneous catalysts.However,the immobilized homogeneous catalysts generally bring the decrease of catalyzed ability compared with homogeneous catalysts itself.So far,there are reported about the effect of the supporter to the homogeneous catalysts itself.But,the results are still original.Still no research was reported for the effect of chiral in supporter and homogeneous catalysts itself.Recently years,the research of chiral polymer catalysts got great progress,which provided new chance for catalyzed asymmetrical reaction.We expect to use the chiral polymer as supporter to bond the chiral camphor ligand to study the effect of chiral center between polymer supporter and camphor ligand.From this research the positive coupling effect are expected and enlarged the chiral catalyzed abilities.In the meantime,the aim of recovery and reuse the catalyst to reduce the pollution of metal ionic was also got realization.Therefore,the concept of high efficiency,environmental protection and sustainability got practice in this research.The main content of this thesis includes the following three parts:In the first chapter,the basic concept of the polymer and its application in asymmetric catalysis are briefly introduced.The research progress of the Schiff base catalyzed asymmetric reaction and the research progress of asymmetrical Henry reaction are also introduced.In the second chapter,the synthesis of camphor amino alcohols has been carried out through the D-camphorsulfonic acid.The synthesis of polymer monomers,self-polymerization of monomers and the synthesis of block copolymers were also reported.The structure was confirmed by nuclear magnetic resonance spectroscopy,infrared absorption spectroscopy and gel permeation chromatography.X-ray photoelectron spectroscopy was used to determine the Cu ion in catalysts.Laser particle size analyzer,transmission electron microscope were employed to determine the copolymer core-shell structure,particle size around 112nm.In the third chapter,catalytic asymmetric Henry reaction was process.The synthesis of the copolymer ligands coordinated with copper salts to catalyze the reaction of aldehydes with nitroalkanes.Through the screening of the reaction conditions,the ligand L2 was determined to be the best polymer ligand,Complexed with CuCl,tert-butyl alcohol as the solvent,and the best catalyzed ability was obtained under the room temperature.The recovery and reused ability were also examination.The copolymer catalyst can reuse four times under almost the same catalyzed ability.Later,the nitroethane and aldehydes as substrates for the two chiral centers were carried out.