The Synthesis And Application Of The Dendritic Molecule Based On The Ferrocenyl Small-Ring Aza-Heterocycle Ligand

In this thesis, a series of N-ferrocenylmethyl aziridino small ring ligands bearing dendrimers were designed and synthesized and the asymmetric ethylation of different aldehydes were studied in the presence of catalytic mounts of the chiral ligand. After the reaction, the chiral ligand could be recovered and reused.1. The design and synthesis of N-ferrocenylmethyl aziridino small ring ligands bearing dendrimersChiral ligand6was prepared from cheap and readily available L-serine1by a series of reactions, and then removed of protecting group in the presence of TBAF. After that, chiral ligand6coupled with different generations of dendrimers derivated three novel chiral compounds14a,14b and14c. Their structures were all characterized by1H NMR,13C NMR, IR, HRMS, and used14b as a model, it was investigated the influence of different solvents on the yield of such reactions. 2. The application of N-ferrocenylmethyl aziridino small ring ligands bearing dendrimers in the catalytic asymmetric addition of diethylzinc to aldehydes In the optimal amount of ligand and the optimum reaction temperature, it was focused on the catalytic activity and enantioselectivity of ferrocene aza small ring ligands containing dendrimers with different generations in the catalytic asymmetric addition of diethylzinc with a variety of aldehydes. The experiments showed that the catalytic activity and enantioselectivity of chiral ligand6was poor, and chiral ligand14c was not good also, it was maybe due to the dendrimer with higher generation embedding the coordination sites in the reaction with diethylzinc. With lower generation14a or14b, the reaction was best achieved more than99%excellent chemical yield and ee value up to98%.3. The recovering and reusing of N-ferrocenylmethyl aziridino small ring ligands bearing dendrimers The chiral ligand14b was used as catalyst to promote the asymmetric addition of diethylzinc to arylaldehydes, it could be recovered and reused through filtration by adding hexane after the end of the reaction. It showed that ligand14b could be repeatedly used three times, while the catalytic activity and enantioselectivity did not change much.