Construction Of C-S Bond Based On Inorganic Sulfur Source

Transition-metal-free catalytzed sulfur insertions are one of the most hot research field of sulfur chemistry.Organo sulfur compounds widely exist in natural products,new drugs,and organic synthesis intermediates.In recent years,many studies have focused on the construction of C-S and S-N bonds.In this thesis,we developed C-S bond construaction reactions by coupling reactions and cyclization reaction of inorganic sulfur under transition-metal free conditions to synthesis of high potential pharmacological and biological activities sulfur-containing compounds.The work mainly consists of the following three parts:In the first part,a transition-metal-free process for the synthesis of unsymmetrical sulfides via dual C-S bond formation by one-pot three-component reaction of alcohols,organo-halides,and odorless sodium thiosulfate in water has been developed.In addition,Bunte salt is the key intermediate for the construction of various unsymmetrical aryl sulfides.In the second part,a novel[4+l]-type cycloaddition reaction between ?,?-alkynic hydrazones and potassium thiocyanate has been developed for the synthesis of N-iminoisothiazolium ylides.The transformation features wide substrate scope,functional tolerance,and easy operation.This investigation involves C-S/S-N bond formation under transition-metal-free conditions.This protocol provides a simple operation and economical strategy toward synthesis of N-iminoisothiazolium ylides from inorganic sulfur source.In the third part,trisulfur radical anion(S3'?)mediated reactions with in situ formed?,?-usaturated N-sulfonylimines and a-Chlorosulfonohydrazides for the construction of isothiazoles and 1,2,3-thiadiazoles has been developed.The reaction does not requiret diazo groups,which provides a simple,safe and efficient method for the construction of sulfur-containing heterocyclic compounds from inorganic sulfur source.