Designing And Synthesis Of Chiral Organocatalysts And Their Applications In Asymmetric Michael Addition Reactions

1. Synthesis of chiral aliphatic–aromatic diamines and their application in the direct asymmetric Michael addition reactions of ketones and nitrostyrenesA series of new highly efficient chiral aliphatic–aromatic diamine catalysts derived from L-proline have been designed, synthesized and successfully applied to the asymmetric Michael addition of ketones with nitroolefins under solvent-free conditions without any acidic additives. The desired adducts were obtained in high yields with excellent enantio- and diastereoselectivities. The influence of catalysts'structure, catalyst loading, additives, solvents and substrates'structure to the yields and enantioselectivities of the adducts was investigated.2. Designing and synthesis of novel chiral sulfone–pyrrilidine catalyst and its application in the asymmetric Michael addition reaction and Aldol reactionA novel chiral amino sulfone catalyst has been synthesized and applied to the asymmetric Michael addition of cyclohexanone with nitroolefins under solvent-free conditions with excellent catalytic activities. Sulfuryl was first introduced in the designing of organocatalysts, and successfully achieved highly enantioselective catalysis for asymmetric carbon–carbon bond formation reactions.3. Synthesis of non-natural amino acids containing two stereogenic centers and multifunctional groups via dynamic kinetic resolutionChiral amino acids and their derivatives were regarded as the biological and pharmaceutical intermediates and the important building blocks for the preparation of natural products and peptides. From the perspective of green chemistry, we envisaged that Michael addition of benzylidene oxazolinone organocatalyzed via tertiary amine-thiourea yielded chiral amino acids'precursor without the introduction of metal, followed by dynamic kinetic resolution of acridine lactone by ring-opening reaction with thiophenol. Accordingly, nonnatural amino acids containing two stereogenic centers and multifunctional groups were obtained.