Study On The Oxidative Coupling Reaction Of Cyclic Ethers And Aromatic Alkenes

As an important organic reaction,the difunctionalization reaction of olefins can synthesize multi-site reaction products in one step economically and efficiently,and convert the starting materials into a variety of biologically active compounds.Therefore,the research on the difunctionalization reaction of olefins is very important.In addition,the directα-functionalization reaction of ether derivatives catalyzed by transition metals has attracted great attention of chemists due to its high atom economy and the green chemical characteristics of the reaction.α-functionalized ether fragments are widely observed in many biologically active molecules and industrial materials.However,due to the special structure of the ether,it has a certain inertness,and its application in the reaction has become a difficult task.But in recent years,scientists have made great progress in this area,including cross-coupling reactions with aromatics,alcohols,alkanes,alkynes,and alkenes.Despite these remarkable achievements,the directα-functionalization of ethers and olefins has received less attention.Therefore,we conducted a series of research and discussion on the cross-coupling of olefin aryl and alkenyl azide with cyclic ether,and synthesized a series ofα-oxyalkyl ketones.The main content of this paper has the following three chapters:Chapter 1.Research progress of radical C-H activation/cross-coupling and unactivated ether through cross-dehydrocoupling forα-C(sp~3)-H functiona-lizationThe latest progress of free radical C-H activation/radical cross coupling and the research progress of the functionalization of unactivated etherα-C(sp~3)-H through cross dehydrogenation coupling are briefly reviewed.Chapter 2.Visible light-promoted oxidative coupling reaction of styrene and cyclic etherThe oxidative coupling reaction of aryl olefins and cyclic ethers under the promotion of visible light was explored.Through the hydrogen atom transfer route,iodobenzene diacetate was used as the oxidant,TBHP was the free radical initiator,and the C(sp~2)-C(sp~3)bond coupling was realized at room temperature.Series ofα-oxyalkyl ketones has good regioselectivity and yield.This reaction has good yield and functional group compatibility,and is simple to operate and mild in conditions.The method has mild conditions,low cost and simple operation.Chapter 3.Tandem Denitrogenation Oxidative Coupling Reaction of Phenyl Vinyl Azide and Cyclic Ether Under Metal-Free ConditionsThe reaction of phenyl vinyl azide and cyclic ether to synthesizeα-oxyalkyl ketone under heating conditions was explored,so as to realize the coupling of C(sp~2)-C(sp~3)bonds.The experimental results showed that KI was used as the additive,TBHP was used as the oxidant,and the phenylvinyl azide compound was heated in tetrahydrofuran at 60°C and reacted for 12 h to obtain theα-alkoxylation product with moderate to good yield.The method has mild conditions,no metal catalysis,low cost and simple operation.