Construction Of Benzosulfonimide Derivatives By Tandem Cyclization/SO₂ Insertion Reaction Of N-Cyanamide Olefins Involving Sodium Metabisulfite

Sulfonyl compounds have very important roles in biology,medicine,materials and other fields.In recent years,the method of introducing sulfonyl groups into organic molecules by SO₂ substitution has gradually become an important means of synthesizing sulfonyl compounds.In this paper,we develop a strategy for the construction of benzosulfonimide derivatives by tandem cyclization of radicals with N-cyanoalkenes under green and mild conditions through SO₂ insertion,where the inorganic SO₂ substitute"Na₂S₂O₅"is used as both a reducing agent and a source of SO₂ in the system.The main points of this paper are summarized as follows:Part Ⅰ:we focus on the application of SO₂ substitution,which plays a reducing role in the system,to the synthesis of sulfonyl compounds and elaborate on the intention of this paper.Part Ⅱ:we have described the common methods for the synthesis of benzosulfonimide derivatives.And the fluoroalkyl-substituted benzosulfonimides were successfully constructed by the tandem cyclization/SO₂ insertion reaction of fluoroalkyl radicals with N-cyanamide olefins.The utility of the reaction was also verified by amplification and conversion experiments.In addition to this,we also made a preliminary exploration of whether other radical precursors can be used to obtain the corresponding benzosulfonimides under this condition,where aryl diazonium salts were used as a radical source,and we also achieved double SO₂ insertion.