Photocatalytic Aza-Semipinacol Rearrangement And Olefin Functionalization

Last few years,visible light photoredox catalysis has become a focus of chemists’ research due to its environmentally friendly,highly efficient,and operationally simple,etc.The general mode of visible light catalysis is that metal complexes or organic dyes react further with organic substrates by producing free radical through a single electron transfer process or producing a reaction intermediate an energy transfer process.The pinacol rearrangement and the functionalization of olefins have become the key steps in the construction of various natural products and drug molecules,and pinacol rearrangement and functionalization of olefins have important research values.In this dissertation,the latest advances in the field of visible light photoredox are introduced in detail through alkyl radicals,nitrogen radicals,phosphonyl radical and other radicals,and aza-semipinacol rearrangement and functionalization of olefins are achieved through visible light redox catalysis.This paper is mainly divided into the following three parts:Part I,This chapter described the application of alkyl radicals,nitrogen radicals and other free radicals generated by visible light catalysis in organic synthesis and systematically summarized recent advances in the field of visible light photoredox catalysis.Part II,This chapter firstly introduced the application of pinacol rearrangement and azapinacol rearrangement in organic synthesis.On this basis,we designed and developed a visible light-catalyzed aza-pinacol rearrangement reaction: generated nitrogen radicals via visible light,and aryl-substituted methylenecyclopropane as a radical acceptor.Finally,stabilized imine product is obtained by rearrangement and then further oxidized to obtain γ-butyrolactone.Part III,This chapter firstly introduced the research methods of visible light catalytic olefin functionalization and its application in organic reactions.On this basis,we developed a method of visible light photoredox catalysis for the styrene methyl esterification using iodobenzene diacetate as a source of methyl radical and p-methoxystyrene as a acceptor.