[3+3] Cycloaddition of Azomethine Imine: Synthesis of Bi‐ or Tricyclic N‐Heterocycle

Synthesis of six‐membered bicyclic, tricyclic or tetracyclic N‐heterocycles are important due to enormous use of such scaffolds in bioactive natural products, agrochemicals and in pharmaceuticals. [3+3] cycloaddition of azomethine imine for the construction of such heterocycles is less explored but also a genuine approach with the other method like [4+2] and [2+2+2] cycloaddition. Hence, the literature survey in this area is utmost significant. The delights and difficulties of [3+3] cycloaddition of azomethine imine have been deliberated thoroughly to elucidate this highly mounting field in this literature study. Herein, we report a vast synthetic method [base catalyzed, metal catalyzed (racemic and asymmetric), phosphine catalyzed, NHC and Lewis acid catalyzed] for the synthesis of di, tri and tetra‐nitrogen containing heterocycles via [3+3] cycloadditon reaction of azomethine imine.