Olefin Sulfurization Of Dimethyl(methylthio)sulfonium Triflate (MeSSMe₂OTf)

In recent years,the synthesis of various sulfur compounds has become an popular topic of organic chemistry.In which,construction of molecules containing sulfur atom on the basis of sulfonium ion intermediates represents one of the most important tools.This thesis firstly reviews the reactions starting from different types of sulfur sources,following by the formation of sulfonium ion intermediates with alkenes and alkynes,which then are transformed to the corresponding sulfur-containing compounds in the presence of various nucleophiles.We speculate that the sulfonium ion formed by the reaction of dimethyl(methylthio)sulfonium Trifluoromethanesulfonate(DMTSM)and olefins should be able to undergo ring-opening addition by the attack of different types of carbon nucleophiles,therefor lead to the synthesis of sulfur ether derivatives by difunctionalization of olefins in a system that free of metal-catalysis.In this regard,the following parts are included in this thesis.1.Introduction of the background on the synthesis of thioethers from alkenes or alkynes.2.DMTSM promoted sulfenoarylation of alkene.A catalyst-free sulfenoarylation of styrene has been achieved by using DMTSM as the activator and with arylzinc reagent as the carbon nucleophile.Benefit from employing the less covalent carbon-metal bond(C-Zn)derived nucleophile,the reaction is well tolerated with a wide scope of functional groups.2.DMTSM promoted sulfenoallylation of alkene.On the basis of the sulfonium intermediate that generated by mixing DMTSM and olefin substrate,a transition-metal free sulfenoallylation of carbon-carbon double bond has been accomplished in the presence of allyl tin reagent.The reaction is able to convert different types of olefins to the methylthioether derivatives under mild conditions.The protocol further expands the substrate compatibility of the DMTSM promoted sulfenofunctionalization of olefin.