The Catalytic Radical Reaction Of Cyclic Sulfonyl Aldimines With Tertiary Cyclic Alcohol And Cyclic Secondary Amine

As organic synthesis intermediates,cyclic sulfonyl aldimines and their derivatives can synthesize a series of natural active substances and be widely used in medicine,pesticides and other fields.Because of its easy preparation and stable chemical properties,it has been used as a reaction substrate for organic synthesis methodological research and has achieved a lot of results.At present,its research mainly focuses on nucleophilic addition reactions,cycloaddition reaction,ring expansion and ring opening reaction.There are few reports on its application in the study of free radical reactions.Therefore,synthesizing a series of cyclic sulfonimides and their derivatives,and applying them to the study of free radical reactions,to provide pharmacists with new synthetic strategies for the development of new natural drugs has become the focus of this topic.This paper mainly focuses on the study of the catalytic free radical reaction of cyclic sulfonyl aldimines with tertiary cyclic alcohols and cyclic secondary aminesfrom two aspects.In the first section,we designed and prepared a Silver salt-catalyzed ring-opening radical reaction of cyclic sulfonyl aldimines and tertiary cyclic alcohols The selective functionalization of inert C-H bonds through catalytic ring-opening radical reaction is extremely attractive in organic synthesis in recent years.Here,we firstly describe a silver-catalyzed direct C-H functionalization of cyclic N-sulfonylated imines with cyclopropanols and cyclobutanols via radical C-C bond cleavage strategy under mild reaction conditions.The corresponding products were generated in moderate to good yields(32-91%).In addition,a gram-scale reaction and synthetic transformation of the product were performed.Experimental studies show the reaction undergoes a radical process.In the second section,we developed a Organic photocatalytic research on the C-N bond coupling reaction of cyclic sulfonyl aldimines and cyclic secondary amines An organophotocatalyzed C(sp2)-H/N-H cross-dehydrogenative coupling of cyclic aldimines with aliphatic amines has been disclosed,which represents the first example for visiable-light-induced C-H amination of N-sulfonylated imines.This methodology enables the streamline assembly of amine derivatives via radical mediated C-N bond formation.The current protocol features transition-metal-free,external oxidant-free,mild conditions,good functional group tolerance and good yields.