Nitrene-mediated Aminative N–N–N Coupling: Facile Access to Triazene 1-Oxides

Significant strides have been made in the realm of nucleophile-electrophile coupling reactions over recent decades. However, the development of innovative strategies for nucleophile-nucleophile coupling is still highly sought after. Among these, aminative coupling, especially when involving two nitrogen-connected nucleophiles, is not only rare but also exceedingly challenging. In this work, we present a novel nitrene-mediated aminative N–N–N coupling reaction that employs an anomeric amide as a key reagent to connect amines with nitrosoarenes. This innovative method capitalizes on the in situ generation of an aminonitrene intermediate, which is efficiently captured by nitrosoarenes. The resultant reaction offers a direct, mild, and highly efficient pathway for synthesizing triazene 1-oxides, thereby establishing a new paradigm for aminative coupling between nucleophiles. Our mechanistic studies demonstrate that the \textit{N}-substituents of the amine have a profound impact on the reactivity of the aminonitrene intermediate. Additionally, complementary computational studies suggest that aryl nitroso and aminonitrene coupling is significantly favored due to the substantial reduction in distortion energy, outcompeting alternative nitrene dimerization pathways.