Synthesis Of Thiophene And Deuterium Thioalcohol Compounds Based On Xanthate

Organic sulfur compounds are widely used in many fields such as life science,drug molecules,functional materials and so on because of their characteristics.Most of the existing methods for synthesis of organic sulfur compounds require transition metal catalysis,harsh reaction conditions and poor tolerance of functional groups.Therefore,it is of great significance and value to develop simple and efficient methods for construction of organic sulfur compounds.Based on xanthate as the medium,this research paper constructs C-S bond and undergoes subsequent conversion reaction to synthesize sulfur compounds,and C(sp~3)-H deuterization reaction,and develops a new method to synthesize a series of organic sulfur compounds with simple operation.The specific contents are as follows:In the first chapter,the importance of organic sulfur compounds is introduced,and the selection of sulfur sources and the problems of sulfuration,as well as the application of xanthates are described.The synthesis methods and applications of thiophene heterocycles and thioethers in recent years and the research methods of C(sp~3)-H bond deuterization are reviewed.Finally,the purpose,content and significance of this research are introduced.In the second chapter,a method of regioselective synthesis of thiopheno[2,3-b]pyridine and thiopheno[2,3-b]quinoline derivatives via hydrocarbon functionalization without transition metal catalysis was studied,and the post-functionalization reaction of thiopheno[2,3-b]pyridine was studied,which confirmed the application prospect of this method.The mechanism study showed that thiophene[2,3-b]pyridine was synthesized by sulfuration and thiocyclization.In the third chapter,xanthate was developed as mercaptan precursor,and the corresponding pyridine sulfide and aniline sulfide derivatives were synthesized by thionucleophilic substitution reaction with halopyridine and halonitrobenzene and desulfurization and carbon oxidation reaction.The reaction does not need to use transition metal catalysis,and avoids the direct use of malodorous mercaptan.The reaction has the characteristics of medium to excellent yield and good substrate universality.In the fourth chapter,a kind of strategy of synthesesα,βdeuterated mercaptan was developed via halogenated hydrocarbon without transition metal catalysis,using cheap and easily available deuterium water as the deuterium source and xanthate medium.This method has the characteristics of medium to excellent yield,high deuterization rate,high functional group tolerance and practicability,which enriches the method of C(sp~3)-H bond deuterization of mercaptan.