The Synthesis Of Bis (cyclopentadienyl) Metal Hand Ligand Asymmetric Diethylzinc To Benzaldehyde Addition In

Chiral science may be one of the most important achievements in the past thirty years and chiral molecules act as a very important role both in science and in technology. Asymmetric catalysis is a very important and most attractive way for preparing chiral compounds, because a little chiral catalyst can get a great deal chiral compounds and the reaction catalysed by chiral catalyst is friendly to the environment. In recent thirty years, asymmetric catalysis has been the advanced frontier in chemistry.In asymmetric catalysis, chiral ferrocenes were proved to be a type of effective catalysts due to their particular structures and electronic effects. In this dissertation, we have prepared a series of chiral ferrocenyl P-N ligands from ferrocene and easily available L-proline, then parts of these ligands were applied in symmetric catalysis reaction. The structures of these new compounds were fully determined by ¹H NMR, ¹³C NMR and ³¹P NMR, and one representative characterized by single-crystal X-ray diffraction methods.On the one hand, we prepared (S)-(R)-PPFA and (R)-(S)-PPFA through the reactions of Ph₂PCI with R- or S-intermediate N, N-dimethyl-α-ferrocenylethyl amine prepared from ferrocene through Vilsmeier reaction, Grignard reaction, Esterification, Aminolysis reaction and Resolution reaction, then prepared (S)-(R)-PPFOAc and (R)-(S)-PPFOAc through the reactions of (S)-(R)-PPFA or (R)-(S)-PPFA with acetic anhydride.On the other hand, we prepared a series of chiral pyrrolidine derivatives through amino protection, Esterification, Grignard reaction, and deprotection from L-proline. Then, we prepared the new ligands through the reactions of the chiral pyrrolidine derivatives with (S)-(R)-PPFOAc or (R)- (S)-PPFOAc.Finally, we catalysed the reactions of benzaldehyde with diethylzinc by the new chiral ligands we had prepared, then determined the structure of the product by ¹H NMR, the ee by HPLC, and discussed the possible mechanism.In short, some creative work is finished: 1. Based on literatures at hand, we devised a appropriate synthesis route of N, N-dimethyl-α-ferrocenylethylamine from ferrocene.2. A series of new chiral ferrocenyl P-N ligands were prepared from ferrocene and easily available L-proline.3. The reactions of benzaldehyde with diethylzinc were catalysed by the chiral ligands we have prepared, all the ee were determined,the possible reaction mechanism was discussed.