Research On The Construction Of Sulfoxides Via C(sp~3)-H Functionalization Of Free Radicals In Alkanes

Efficient synthesis of molecules is essential for drug development.C-H functionalization provides a highly atom-economical,step-economical,and redox-economical direct transformation strategy by avoiding pre-functionalization,offering a new efficient approach for molecular synthesis.Alkanes are abundant and inexpensive resources in nature,making the development of direct functionalization strategies for C(sp~3)-H bonds in simple alkanes highly meaningful.However,most C(sp~3)-H bonds are inert,making such transformations challenging.In fact,free-radical oxidative dehydrogenative coupling of alkanes provides a promising strategy and approach for their C-H functionalization.This article focuses on the research of constructing sulfoxide compounds through the oxidative dehydrogenative coupling reaction of simple alkanes and thiols via C(sp~3)-H functionalization.Article consists of two main parts:1.The recent research and application of free-radical C(sp~3)-H functionalization reactions of simple alkanes are reviewed.The strategies for constructing C-C,C-N,C-O and C-S/Se bonds through free-radical oxidative dehydrogenative coupling are classified,and some reaction mechanisms are described and summarized.2.The direct C(sp~3)-H functionalization reaction of alkanes and thiols via oxidative dehydrogenative coupling is investigated,which generates new C-S bonds and S=O double bonds.This reaction has the characteristics of using readily available reagents,high step and atom efficiency,and provides an efficient and concise approach for the synthesis of sulfonamides.The reaction has good generality and can be carried out on a kilogram scale,demonstrating its potential for practical applications.Mechanistic studies confirm that the reaction is a free-radical process,and the oxygen atom in the sulfonamide is derived from the water in the system.