Design And Synthesis Of Novel Planar Chiral N-Containing Nucleophilic Catalysts And Their Applciations In Asymmertric Reaction

Catalytic asymmetric synthesis using chiral organic catalysts is one of the most effective approaches to obtain chiral compounds, which chiral N-containing nucleophilic catalysts is novel organic catalysts with high catalytic activity and high enantioselectivity and has been employed in a series of asymmetric catalytic reactions successfully. This thesis mainly focused on the design and synthesis of novel planar chiral N-containing nucleophilic catalysts, and their applications in kinetic resolution of different types of racemic secondary alcohols. Our research work mainly includes the following three aspects:1. Design and synthesis of novel planar chiral N-containing nucleophilic catalystsOur design concept is combined with Fu's planar chiral DMAP derivatives and Birman's central chiral DHIP derivatives nucleophilic catalysts. Chiral nucleophilic catalystsⅡ-la-d,Ⅱ-2a-d,Ⅱ-3 andⅡ-4, which based on ferrocene scaffold orπ-Cyclopentadienyltetraphenylcyclobutadiene cobalt scaffold were designed and synthsized. Thus it provides the foundation for the further asymmetric catalysis reactions.2. The application of novel planar chiral N-containing nucleophilic catalysts in kinetic resolution of arylalkyl carbinolsThe optimal reaction conditions for catalytic KR was established through investigating the catalyst, solvent, anhydride, reaction temperature and catalyst loading, respectively. With these conditions, the generality and substrate scope were probed, furnishing good S value up to 534. Exploiting the improved selectivity at lower temperatures further raised the S value to 801 at-20℃and 1892 at-40℃. This is the highest S value obtained by non-enzymatic chiral nucleophilic catalyst by far.3. The application of novel planar chiral N-containing nucleophilic catalysts in kinetic resolution of aryl-substituted allylic alcoholsThe first efficient nonenzymatic acylative kinetic resolution of aryl-substituted allylic alcohols is reported to date, furnishing moderate to good ee value and selectivity factors. Some of the substrates was allowed to be isolated with excellent enantiomeric purity (>99% ee) if the reaction was allowed to proceed to higher conversion (～60%). This method provides a new route to syhthesis optically enriched aryl-substituted allylic alcohols.