Cyclization: A Useful Approach for the Synthesis of Nitrogen Heterocyclic N-Oxides

Nitrogen heterocyclic N-oxides attract enormous interest in synthetic chemistry, medicinal chemistry, functional materials and energetic materials. Cyclization reaction turns out to be an important and highly rewarding protocol for the construction of N-heterocyclic N-oxides and different types of organonitrogen compound could be utilized as crude materials. In this work a review of recent advancement in the generation of pyrazole, imidazole, triazole, triazine, tetrazine, isoquinoline and other N-heterocyclic N-oxides and their derivatives via cyclization reactions is presented.