Synthesis Of ?-cyano Sulfone Via Thermal Rearrangement Of 1,4-disubstituted Triazole Mediated By Carbene And Radical Species

N-sulfonyl-1,2,3-triazole was used as carbene resource in the recent decade,and played an important role in organic synthesis.The reaction mode of N-sulfonyl-1,2,3-triazole includes:1)Producing ?-imino metal carbene under the catalysis of transition metal,which bears electrophilic carbene carbon atom and nucleophilic imine nitrogen atom;the ?-imino metal carbene could undergo many important chemical reactions,such as:cyclopropanation,X-H bond insertion,1,2-migration,and other types of carbene reactions,and it is widely used in the synthesis of nitrogen-containing(heterocyclo)compounds.2)Ring-opening reactions could be promoted by Lewis acid,followed by fluorination or transannulation reaction.3)Under thermal conditions,ketenimine could be obtained by rearrangement of N-sulfonyl-1,2,3-triazole,and the subsequent intramolecular cyclization delivered ring products.This thesis studied the thermal reaction of N-sulfonyl-1,2,3-triazole for synthesis of ?-cyano sulfone,which could be further transformed to fused multi-cycle molecules.The reaction had a broad substrate scope and tolerated various functional groups.Carbene and radical species were proposed as the key intermediates and ketenimine was captured by an intramolecular reaction.New insight into the properties of N-sulfonyl-1,2,3-triazole and the corresponding ketenimine was provided.