ABSTRACT N ‐Bromosuccinimide (NBS) is a versatile and widely employed reagent in organic synthesis, valued for its mild reactivity, operational simplicity, and high selectivity. Since its introduction, NBS has been a cornerstone in bromination reactions, particularly allylic and benzylic bromination via radical pathways. Beyond classical halogenation, NBS has found extensive applications in oxidation, cyclization, functional group transformations, and the synthesis of diverse heterocycles. Its broad substrate compatibility, ability to operate under both radical and ionic conditions, and adaptability to solvent‐free and green chemistry protocols have further enhanced its synthetic utility. This review (2015–present) comprehensively highlights the major applications of NBS in modern organic synthesis, emphasizing mechanistic insights, reaction scope, and recent advancements. Special attention is given to NBS‐mediated heterocyclic construction, including monocyclic rings, five‐ and six‐membered mixed‐atom heterocycles, bicyclic fused systems (saturated, benzofused, and polycyclic), spiro‐heterocycles (monocyclic, heterocycle‐heterocycle, and spiro‐fused hybrids), and miscellaneous heterocyclic frameworks. The review underscores NBS's continuing relevance in both academic and industrial settings as a versatile and sustainable tool for the construction of complex molecular architectures.
Varala et al. (Tue,) studied this question.