Preparation Of Chiral Transition Metal Catalyst To Replace The Indenyl Ligand And Its Application In Asymmetric Catalytic Reactions

The chiral secondary alcohols are important intermediates in the synthesis of drug, pesticide and spicery etc., and there are numerous methods remain the focus of much research activity. Catalytic asymmetry addition of aldehydes and asymmetry reduction of prochiral ketones are two effective methods for preparation of chiral secondary alcohols. These two methods play an important role in academic research and industry.The importance of chirality and the ways of obtaining chiral compounds were briefly reviewed. The role of ligands in catalyzed asymmetric reactions and their classification were elucidated.Three unreported chiral ligands involved indenyl were obtained in this thesis. And these ligands were used to catalyze asymmetry hydrogenation of aromatic ketones and asymmetry allylation of aromatic aldehyde with different kinds of metallic salt and chiral diamine. The effectiveness of these catalytic systems were assessed by the data got from HPLC and GC. The main work includes.1: Several different substituted indenyl ligands were prepared from indenyl lithium (prepared before) and different substituted halides. A new kind of catalytic system was obtained by using lithium salts of indene, 3-butylindene and 3-(4-methylbenzyl)indene prepared in situ to reacted with MCln (M=In, n=3;M=Zr, n=4), then coordinated with chiral Binaphthol. The catalytic activity of this kind of catalytic system were assessed in the asymmetry allylation of aromatic aldehyde. The optimum reaction condition were obtained by trying different solvents and temperatures. The influences of the substituents of aromatic aldehydes and substituted indenes to the effectiveness of the catalytic systems were researched. It was found that Catalytic system Indene-Zr-Binol showed the best results, which gave 74.2% e.e. to 1-(4-methoxyphenyl)but-3-en-1-ol.2: Ligands Single idene-BINlOL-MOM and Double indene-BINOL-MOM were prepared through multi-step reactions, then seven catalytic systems were obtained from derivatives of BINOL, MCl3(M=Ru,Rh,Ir) and chiral diamine(DPEN or Ts-DPEN). The effectiveness of these catalytic systems were assessed in the asymmetric hydrogenation of aromatic ketones. The optimum reaction condition were obtained by trying different temperatures. The influences of the substituents of aromatic ketones to the effectiveness of the catalytic systems were researched. The results showed that all catalysts had high catalytic activity. (yield was up to 99.9%,ee was up to 60.3%).