Asymmetric Synthesis And Applications Of Cinchona Alkaloids

The Cinchona alkaloids can be applied in asymmetric synthesis as efficient chiral reagents, chiral auxiliaries and chiral catalysts. The structure of Cinchona alkaloids and their derivatives include several active sites. In this paper, Cinchona alkaloids derivatives were synthesized and applied in asymmetric Henry reaction. In addition, several multisubstituted bispirooxindoles were synthesized catalyzed by simple Cinchona alkaloids derivatives.We made the researches as follow:In the current work, we designed three novel Phenanthroline-Cinchona ligands, and investigated the Henry reaction of aldehyde to nitroalkane in the presence of6mol%Phenanthroline-quinine ligand and5mol%N-Me-morpholine at0°C, affording adducts in yields ranging from47to86%and ee ranging from66to99%. The structure of the ligands was determined by X-ray diffraction. Most of all, we tested the active of the catalysis.Next, we have applied bifunctional organocatalyst for stereocontrolled cascade Michael-cyclization reaction between methyleneindolinones and isothiocyanato oxindoles under mild conditions. This reaction constructed bispirooxindoles containing three stereocenters,including two spiro quaternary centers. The reaction proceeded within less than1min, with excellent yields enantio and diastereoselectives (yield: up to99%, ee: up to99%, dr:>20:1). The new created bispirooxindole derivatives are simmlar to bioactive compounds.