Organocatalytic Synthesis Of Indole Derivatives And Heterocyclic Axially Chiral Compounds

The skeleton of indole is widely present in various natural products and medicines,and it’s also one of the skeleton that chemists are constantly exploring.Chemists need to develop new methods to obtain indole derivatives because different fields require different kinds of indole derivatives.In addition,heterocyclic axially chiral structures are also widely found in various natural products and drugs.But there are few methods for synthesizing heterocyclic axially chiral structures by using organic catalysts.Our research group took azonaphthalenes as the main research object and selected three nucleophiles such as aldehydes,ketones and pyrazolones,which can efficiently synthesize indole derivatives and heterocyclic axially chiral compounds with potential applications.In the first chapter,the research realized the enamine-catalyzed [3+2] cyclization reaction of azonaphthalenes with aldehydes.We screened the reaction conditions with secondary amines as catalysts,selected the optimal solvent and temperature,and obtained the target product in excellent yield.Then we investigated the applicability of the method and learned that the yield of different substituted products was 77%-98%.It can prove that we have discovered a method to synthesize indole derivatives efficiently.In the second part,the work realized the enamine-catalyzed [3+2] cyclization reaction of azonaphthalenes with ketones.We optimized the reaction conditions by using secondary amines,determined the optimal solvent and temperature,and obtained the target product in excellent yield.Then we investigated the applicable range of the method and found that the yield of different substituted different products was 71%-89%.This can prove that we have found a method to synthesize indole derivatives efficiently.In the third stage,the study realized that the reaction of azonaphthalenes with pyrazolones to generate heterocyclic axially chiral compounds under the catalysis of chiral phosphoric acid.Using chiral phosphoric acids as catalysts,we screened the reaction conditions to find the optimal conditions and obtained the target product with excellent ee value in good yield.Then we tested the scope of application of this method.The yield of the different products was 74%-99% and the ee value was 83-98%.This can prove that we have offered a new method for the efficient synthesis of heterocyclic axially chiral compounds with potential applications.