Application Of Secondary Amine Catalysis In The Synthesis Of Spiro [2,3] Hexane Compounds And Asymmetric Photocatalysis

In this thesis,the asymmetric synthesis of spiro [2,3] hexanes with electron-deficient secondary amines has been studied.At the same time,the application of secondary amines in visible light catalysis has been explored accordingly.This thesis includes the following four sections:Chapter 1: The development and challenges of secondary amine catalysis and its application in visible light catalysisIn recent decades,the development of secondary amine catalysis is relatively complete.The main catalytic modes are divided into enamine catalysis,imine catalysis,SOMO catalysis,and co-catalysis combined with various other catalysis modes.However,the secondary amine catalysis has great challenges in the synthesis of small ring compounds.The development of secondary amine catalyzed small ring compounds has been developed and explored mainly by introducing halogen or halogen-like groups into the substrate.It is of great research value to develop and explore the rules of the secondary amine-catalyzed synthesis of small ring compounds.In addition,the realization of asymmetric visible light catalytic reaction is a hot topic in recent years.As a well-developed chiral control strategy,secondary amine catalysis has been well applied in this field.We briefly introduced the currently developed asymmetric visible light catalysis and summarized the application of secondary amine catalysis in this field.Chapter 2: Synthesis of Spiro [2,3] hexane Catalyzed by Electron-deficient Secondary AmineSpiro compounds have significant advantages over ordinary cyclic compounds in physicochemical properties and pharmacological research due to their high sp3 / sp2 ratio and compact and diverse spatial structure;in view of the fact that spiro compounds are used in biologically active molecules and the pharmaceutical industry In recent years,the study of spiro compounds,especially small ring spiro compounds containing four-membered rings,has received increasing attention from chemists.But the synthesis of small ring spiro compounds has always been a challenge.The traditional method of synthesizing spiro [2,3] hexane is limited to the derivatization of a predetermined three-membered ring substrate or a four-membered ring substrate,and it is difficult to achieve the synthesis of spiro [2,3] hexane.We have used the recently developed electron-deficient secondary amine catalyst to achieve asymmetric synthesis of high-tension spiro [2,3] hexane.Chapter 3: Visible light-catalyzed synthesis of 1,5 dicarbonyl compoundsIn recent years,due to the mild reaction conditions,high reaction efficiency,and environmental protection photocatelysis reaction have attracted the attention of chemists.However,most of the mechanism of visible light catalysis reaction is completed by free radical pathway,except for the reactions in the energy transfer process.Due to the high activity of the free radical reaction,enantioselective synthesis of target products becomes very difficult.We tried to take advantage of small organic molecules catelysis to achieve asymmetric synthesis of 1,5 dicarbonyl compounds via photocatelysis reaction.Chapter 4: Visible Light-Promoted C-H Functionalization: High Enantioselective Construction of Tetrahydroquinoline DerivativesThe activation of C-H bonds has always been one of the concerns of chemists.Carbon and hydrogen are the main elements that make up organic compounds.Therefore,functionalization of C-H bonds,especially selective functionalization of carbon-hydrogen bonds is recognized as a challenging subject.This chapter mainly introduces the progress of visible light catalyzed C-H bond functionalization.Given the understanding of enantioselective visible light catalyzed reactions and organic catalysis,we designed a intramolecular strategy for C-H bond breakage and migration to achieve C-H bond activation.We have achieved the enantioselective construction of tetrahydroquinoline derivatives without using additional photocatalysts.