Visible-Light-Induced Photoredox Dichloromethylation And 1,4-Sulfonyl Transfer Of Electron-Deficient Alkenes

With the rapid development of modern science and technology,more and more social problems have become increasingly prominent,especially health problems,energy problems and environmental problems,which have brought serious challenges to the progress of human society.Therefore,it has become the goal of chemists to develop synthetic methods with mild conditions,sustainable,high efficiency,and simple operation.Visible light is an abundant and renewable energy source in nature.In recent years,the visible light catalysis has received extensive attention in organic synthesis,and it provides an efficient and green access to the construction of diverse complex organic molecules.Dichloromethyl and sulfonyl groups,which can significantly regulate the properties and enhance the biological activities of compounds,are widely exist in pharmaceutical molecules,and are also important units biologically active molecules and natural products.The dichloromethyl and sulfonyl containing compounds have attracted considerable interests,due to their wide applications in many fields,such as antibacterial compounds,insect repellants,as well as anticancer drugs.The main content of this thesis is"the dichloromethylation and 1,4-sulfonyl transfer reaction of electron-deficient alkenes",including:（1）Using N-phenylmethacrylamides and chloroform as raw materials,we firstly developed the dichloromethylation of electron-deficient alkenes with visible light.（2）Using N-phenyl-N-sulfonyl methacrylamides as raw materials,the 1,4-transfer of sulfonyl group was realized with visible light.The details are as follows:1.A visible light-induced dichloromethylation reaction of electron-deficient alkenes was developed.This reaction used N-phenylacrylamides and chloroform as raw materials,[Ir（d F（CF₃）ppy）₂（dtbbpy）]（PF₆）as photocatalyst,Et₃N as reducing agent,and lithium bromide as additive.A series of dichloromethylated products could be obtained in high yields with 35w blue LED irradiation.The reaction has the characteristics of simple conditions,high yields and broad scope of substrates.2.A transition metal-free 1,4-sulfonyl transfer reaction of electron-deficient alkenes with visible light was developed.This method uses N-phenyl-N-sulfonyl methacrylamides as raw materials,4Cz IPN as photocatalyst,K₃PO₄ as base,resulting in a series ofβ-benzenesulfonyl alkenes.The reaction has the characteristics of mild conditions.