Abstract 
         The 1,3-dipolar cycloaddition of azomethine ylides is a versatile and efficient tool
            for the construction of five-membered nitrogen heterocycles. When the azomethine ylide
            is conjugated with double bonds other pericyclic pathways become available, including
            1,5- or 1,7-electrocyclizations, with the latter 8π-electron process having only recently
            emerged as a potentially useful method for the formation of seven-membered heterocycles.
            Under special structural circumstances, multistep rearrangements can also be observed.
            In this account, a summary of our work on the exploration and development of 1,7-electrocyclizations
            of azomethine ylides is presented.
         1 	Introduction
         2 	Electrocyclizations
         2.1 	Reaction of β-Phenylcinnamaldehyde with Amino Acids: The First 1,7-Electrocyclization
            of Nonstabilized Azomethine Ylides
         2.2 	Synthesis of Azepines from Unsaturated Aldehydes and Sarcosine via 1,7-Electrocyclizations
         2.3 	Electrocyclizations of Stabilized Azomethine Ylides
         2.4 	Electrocyclizations of Azomethine Ylides onto a N=O Double Bond
         3 	Conclusions
         
            
Key words 
         
         
            azomethine ylides - electrocyclization - heterocycles
          
       
    
   
      
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