Ring — chain transformations with the participation of the C=N group
In reaction with primary aromatic amines, 3-aryl-3-chloroperinaphthalides form 3-aryl-3-arylaminoperinaphthalides. The ring—chain tautomerism of these compounds has been studied and isomerization has been realized in the 2,3-diaryl-3-hydroxy-2,3-dihydro-1H-benz[d,e]isoquinolin-1-ones.