Design And Asymmetric Catalysis Study Of Novel Chiral Bifunctional Catalysts

Asymmetric catalysis is an important branch of modern organic synthesis methodology.It provides more synthesis methods for chiral drug intermediates and chiral natural products.In this paper,three kinds of chiral novel bifunctional catalysts were designed.Two types were synthesized successfully and were applied to asymmetric catalysis.The main research contents and results of this thesis are as follows,1.Two different synthetic routes were designed to synthesize the target catalyst?S?-8using C₂-axis chiral binaphthol as the starting material.Due to the influence of steric hindrance and intramolecular hydrogen bond,the synthesis of the target catalyst is more challenging.The synthesis of the catalyst is still in progress.2.With Phenylglycine as the starting material,three chiral bifunctional catalysts D-6?a-c?were synthesized in 5 steps.The catalysts was subjected to asymmetric aldol reaction too.As a result,it was found that the target product had diastereoselectivity of 83:17and yield of 31%.3.With trans-4-Hydroxy-L-proline as the starting material,the target chiral bifunctional catalysts L-7 was synthesized in 5 steps.This catalyst was subjected to asymmetric aldol reaction.The results showed that the best condition of aldol reaction is CPME as solvent,10%catalyst and stirred at r.t.for 48h.Under the optimal conditions,the applicability of different ketones and aldehyde substrates was studied.Good yield?up to 99%?and stereoselectivity?the ee value is 99%,and the dr value is 99:1?were obtained.The three types of catalysts designed in this paper are all novel bifunctional catalysts.A novel efficient proline derivative catalysts L-7 was obtained by exploring the asymmetric aldol reaction.With the in-depth study of this type of catalyst is expected to develop more new asymmetric catalytic reactions.Provide new methods for the synthesis of chiral drug molecular intermediates,construction of chiral functional molecules.