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Nitroarenes are readily available compounds that are commonly utilized in reductive processes to form C–NAr bonds via reactive nitrogen intermediates. Recent advances in the development of reductive reactions of nitroarenes using organomagnesium, organozinc, and single-electron transfer reagents are discussed within this short review. 1 Introduction 2 Organomagnesium-Mediated Reductive Reactions of Nitroarenes 3 Organozinc- and Zinc-Mediated Reductive Reactions of Nitroarenes 4 Iodine-Catalyzed Redox Cyclizations of Nitroarenes 5 Titanium(III)-Mediated Reductive Cyclizations 6 Sulfur-Mediated Reductive Reactions of Nitroarenes 7 Alkoxide-Mediated Reductive Reactions of Nitroarenes 8 4,4′-Bipyridine-Mediated Reductive Reactions of Nitroarenes 9 Visible-Light-Driven Reductive Amination Reactions 10 Electrochemical Reductive Reactions 11 Conclusion [ABSTRACT FROM AUTHOR]

tert‐Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert‐butoxide was found to produce N‐hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen‐transfer reaction followed by a 1,2‐phenyl migration. Mechanistic experiments established that these reactions proceed via radical intermediates and suggest that counterion coordination controls whether an oxindole or N‐hydroxyindole product is formed. [ABSTRACT FROM AUTHOR]

A reductive amination process that constructs indoles, carbazoles or benzimidazoles from nitroarenes – irrespective of their electronic or steric nature – was developed that uses CO2 as the source of CO. The process is robust, tolerating common gaseous components of flue gas (H2S, SO2, NO and H2O) without adversely affecting the reductive cyclization. [ABSTRACT FROM AUTHOR]