Biquinoline Synthesis Of Novel Chiral Ligands In Asymmetric Catalysis

A resolution method of novel chiral ligand 5, 5'-biquinoline-6, 6'-diol (BIQOL) was a big problem in the past study.In this study, we improve the resolution method. Racemic BIQOL reacts with D-(+)-Camphorsulfonyl chloride to produce two diastereomers. In accordance with different polarity of the diastereomers be separated. A frist step is obtained the as large as possible ee values'components through column chromatography. In this step ,we can obtain the almost 100 percent of ee values'R- isomer. The second step is take the large number of cross-mixture diastereoisomers to recrystallize. By this step we can obtain the almost 100 percent of ee values's- isomer. Thus we can indirectly split the chiral ligand.Propargyl alcohols are important organic component of complex, particularly optically active propargyl alcohol compounds. Optically active propargyl alcohols can be used in diverse areas including the synthesis of many natural products and medicines. Such as steroids, vitamin E, K, etc. The preparation of chiral propinol are variety of methods. These compounds typically have asymmetric reduction, asymmetric 1, 2-addition, kinetic resolution and so on. But the terminal alkynyl addition to the aldehydes or ketones has a largest and most in-depth study, in the past decade .When reproduce the BINOL catalyzed enantioselective alkynylation of aldehydes, we found greatly improve the enantioselectivity increased Me₂Zn/ phenylacetylene ratio. Then BIQOL was catalyzed enantioselective alkynylation of aldehyde. Several factors were studied ,such as Me₂Zn/ phenylacetylene ratio, BIQOL/Ti(OⁱPr)₄ ratio, solvents,ligand ratio and temperature. Finally different aromatic aldhydes as substrate were applied to this reaction. The experiment result was pretty good.