Reactivity of 3-nitroindoles with electron-rich species.

The indol(in)e building block is one of the "privileged-structures" for the pharmaceutical industry since this fragment plays a central role in drug discovery. While the electron-rich character of the indole motif has been investigated for decades, exploiting the electrophilic reactivity of 3-nitroindole derivatives has recently been put at the heart of a wide range of new, albeit challenging, chemical reactions. In particular, dearomatization processes have considerably enriched the scope of C2[double bond, length as m-dash]C3 functionalizations of these scaffolds. This feature article showcases this remarkable electrophilic reactivity of 3-nitroindoles with electron-rich species and highlights their value in generating diversely substituted indol(in)es. This compilation underlines how these heteroaromatic templates have gradually become model substrates for electron-poor aromatic compounds in dearomatization strategies.