Synthesis And Applications Of Cinchona Alkaloid Derived Bifunctional Amine-Thiourea Catalysts Bearing Sulfonamide As Multiple Hydrogen-Bonding Donors

This thesis focused on the synthesis of cinchona alkaloid derived bifunctional amine-thiourea catalysts bearing multiple hydrogen-bonding donors, and their initial applications in catalytic asymmetric reactions. The catalysts have been synthesized from quinine or quinidine by the one-pot reaction with triphenylphosphine, diisopropyl azodicarboxylate (DIAD) and diphenylphosphoryl azide (DPPA), then treated with triphenylphosphine and carbon disulfide to form cinchona alkaloid derived isothiocyanate, which was converted to the corresponding catalysts after the reaction with various different ammes.In order to illustrate the application of this kind of catalysts, a highly enantioselective Michael addition reaction of 3-aryl-N-Boc oxindoles to phenyl vinyl sulfone has been developed by using quinine derived bifunctional tertiary amine-thiourea-bearing sulfonamide as multiple hydrogen-bonding donor organocatalyst. The reaction scope is substantial and a number of oxindoles could be successfully applied to give the corresponding multifunctional chiral oxindole compounds bearing an all carbon-substituted quaternary stereocenter in moderate to good yields (52-86%) with good to excellent enantioselectivities (83-98% ee).Moreover, the quinine derived bifunctional tertiary amine-thiourea-bearing sulfonamide as multiple hydrogen-bonding donor organocatalyst was also found to be effective catalyst for the asymmetric addition reaction of isocyanoacetate to isatins, affording the optical spirooxindoles with moderate to good yield (53-99%), excellent diastereoselectivity (up to 99:1 dr) and excellent enantioselectivity (up to 97% ee).