N-Nitrosamide chemistry: Synthesis and applications in organic transformations

Nitroso chemistry has gained considerable interest in the fields of chemistry and biology over the past few decades. However, while N-nitrosamines and C-nitrosamines have been extensively studied, N-nitrosamides have received relatively less attention in the literature. In recent years, various synthetic chemists have developed dynamic synthetic approaches to prepare a diverse range of N-nitrosamide derivatives using different nitrosating agents. Further, these nitrosamides have been utilized for the preparation of structurally significant compounds such as amides, esters, thioesters, acids, alcohols, acyl hydrazides, glycouronamides, and heterocycles like indazole scaffolds through transamidation, esterification, thioesterification, reduction and aryne σ-insertion followed by C(sp3)–H bond functionalization strategy under suitable reaction conditions. Moreover, synthesis of other nitrosamides such as nitrosocarbamates, nitrosoureas and nitrososultams is also described. In this brief review, we highlight the progress in this field, focusing on the synthesis and applications of N-nitrosamides in various organic transformations. Moreover, the reaction mechanisms have also been included for the respective reactions. The contents of the review include the following subsections.