Study On The Cascade Cyclization Reaction Involving Isocyanide To Synthesize Indoles And Polysubstituted Benzenes

Due to its unique structural characteristics and reactivity,isocyanide has become very important synthon and reaction component in organic synthesis.In recent years,cyclization based on isocyanide has become one of the research hotspots in organic community.In this regard,we attempt to perform the reactions of isocyanides and other reactive intermediates,thus offers a series of novel cyclizations.This thesis main contains of the following contents:Chapter one gives a brief introduction to the properties,structural features of isocyanides,and their application in many cyclizations.In particular,we also focus our attention on the recent progress of the construction of nitrogen-containing heterocyclic compounds.Chapter two mainly investigates the reactions between isocyanide and N-2’-chloromethylphenyl-4-methylbenzenesulfonamide under basic conditions.This protocol provides a new method for indole derivatives.Further experiments also reveal that aliphatic isocyanides can react with two molecular N-2’-chloromethylphenyl-4-methylbenzenesulfonamides,thus offers a new pathway for the synthesis of structurally complex indole derivatives.This strategy is also distinguished by the mild conditions,good selectivity,and broad substrate scope.Chapter three describes the cascade cyclization of isocyanide and propargylic ester.This reaction is proposed to proceed through rearrangement,intramolecular cyclization,ring opening,and acyl migration,thus provides a new method for construction of structurally complex polysubstituted benzenes.This reaction can take place without the addition of any transition metal catalyst.In addition,two molecular isocyanides were used to finish the above-mentioned transformation.And the reaction condition is very mild.