Study On The Iodine Element Participated Bifunctional Reaction Of Alkynes

Alkenes,one kind of important structure motifs,occupy a significant position in the pharmaceutical,agricultural chemicals,materials and other fields.Therefore nowadays how to efficiently synthesis this kind of compounds with green methods is one of the most important issues of organic synthesis.Among all these methodologies,Free radical mediated bifunctional reactions of alkynes appears to be the most powerful one with high atom economy.In this thesis,based on the literature review,we propose strategies for synthesizing iodinated olefinic compounds,by addition of free radicals to alkynes,which form alkenyl radical intermediates and then are captured by elemental iodine.This dissertation is made up of three chapters:(1)In this part,different kinds of free radical additional reactions of unsaturated bonds were summarized,especially the progress of bifunctional reactions of alkyne compounds.The contents are classified by different kinds of radicals.(2)In this part,we have developed a high efficient and high stereoselective method for iodonitration of alkynes.With alkynes as starting materials,iodine as halogen source and tert-butyl nitrite as green nitro radical precursor,this reaction undergoes a quite mild condition and simple process to achieve bifunctionalized styrenes,providing an environmentally friendly method for the synthesis of ?-iodonitro styrene compounds with higher Z/E ratio.A series of alkyne compounds can be applied to this method.(3)In this part,a novel method for the construction of thiocyanate-containing?-iodothiocyanate Styrene compounds has been developed.With iodine as halogen source,cheap and easily achieved K2S2O8 as oxidant and non-toxic KSCN as thiocyanate radical precursor ?-iodothiocyanate styrenes are obtained under mild condition.This reaction provides a convenient method for the synthesis of?-iodothiocyanato styrene compounds.