Cyclization Cascades Or Cycloaddition Reactions Of Unsaturated Hydrocarbons

The aryl sulfone functional groups are a class of important building blocks in synthesis as well as are common structural units that widespreadly presented in natural products,drugs and functional materials.It plays an effect on the properties of the drug and the material.Traditional methods for the introduction of sulfone functional groups into the existing compounds employ toxic and odorous thioethers or thiols as the starting materials that has bad effects on the environment and the human body.Therefore,strategies using arylsulfonyl chlorides,arylsulfonyl hydrazides or sodium arylsulfonates as the sulfone functional group sources for sulfone functional groups into organic molecules has attracted the interest of chemists.Aromatic compounds are widespread in natural products and drug molecules.It have broad application prospects which have attracted much attention of organic chemists.Oxiranes is commonly used to construct aromatic compounds because it has a large ring tension and is easy to open under light,electricity,heat,and lewis acid conditions.In this thesis,we mainly studied the cyclization cascades reaction of 1,6-diene with benzenesulfonyl chloride which established the synthesis method of sulfone-functional compound.A method for synthesizing an Ar-Ar'type aromatic hydrocarbon compound by a cycloaddition reaction of 2-aryloxiranes with an alkyne.This paper will be divided into three parts for detailed explanation:?1?In recent years,the free radical-induced unsaturated hydrocarbon conversion reaction and its development history are reviewed.Mainly introduced from three aspects:a.olefin functionalization reaction,b.alkyne functionalization reaction,c.alkyne cyclization reaction.And the Lewis acid-catalyzed cycloaddition reaction and its development process are reviewed and discussed.?2?The cyclization cascades reaction of 1,6-diene with a benzenesulfonyl chloride derivative is developed.The reaction was carried out under the optimal conditions of 10mol%CuBr,10 mol%ligand,2 equiv K₂CO₃,2 ml PhCF₃,Ar for 12 h.Through the cleavage of the sulfur-chlorine bond in the benzenesulfonyl chloride derivative,two new bonds of carbon-sulfur and carbon-chlorine were constructed by radical mechanism.?3?The cycloaddition reaction of 2-aryloxiranes and alkynes is presented under optimal conditions of 10 mol%ZnCl₂,3 equiv BF₃.Et₂O,2 ml CH₂Cl₂,and reacted at room temperature for 30 minutes.The reaction is catalyzed by anhydrous zinc chloride,and boron trifluoride etherate is coordinated with oxygen to form a ion intermediate.The phenylacetylene attacks the ion intermediate to form an alkenyl cation intermediate,and then attacks the benzene ring,and finally dehydrates to form a aryl compound.Among them,the pharmaceutical structure of the estrone derivative is also sufficient to participate in the reaction.The raw material is easy to obtain,the conditions are simple,the reaction time is short,and the functional group is highly tolerant.