Organic Chemistry Portal



Sodium Sulfide: A Sustainable Solution for Unbalanced Redox Condensation Reaction between o-Nitroanilines and Alcohols Catalyzed by an Iron-Sulfur System

Thanh Binh Nguyen*, Ludmila Ermolenko, Ali Al-Mourabit*

*Centre de Recherche de Gif-sur-Yvette, Institut de Chimie des Substances Naturelles, CNRS, 91198 Gif-sur-Yvette Cedex, France, Email:,

T. B. Nguyen, L. Ermolenko, A. Al-Mourabit, Synthesis, 2015, 47, 1741-1748.

DOI: 10.1055/s-0034-1380134 (free Supporting Information)

see article for more reactions


Sodium sulfide in combination with iron(III) chloride hexahydrate promote an unbalanced redox condensation reaction between o-nitroanilines and alcohols, leading to benzimidazole and quinoxaline heterocycles. Beside the role as a precursor for an iron-sulfur catalyst, hydrated sodium sulfide is also an excellent noncompetitive, multi-electron reducing agent.

see article for more examples

Cobalt- and Iron-Catalyzed Redox Condensation of o-Substituted Nitrobenzenes with Alkylamines: A Step- and Redox-Economical Synthesis of Diazaheterocycles

T. B. Nguyen, J. Le Bescont, L. Ermolenko, A. Al-Mourabit, Org. Lett., 2013, 15, 6218-6221.

Benzazoles from Aliphatic Amines and o-Amino/Mercaptan/Hydroxyanilines: Elemental Sulfur as a Highly Efficient and Traceless Oxidizing Agent

T. B. Nguyen, L. Ermolenko, W. A. Dean, A. Al-Mourabit, Org. Lett., 2012, 14, 5948-5951.

Key Words

redox condensation, iron-sulfur, benzimidazoles, atom economy, sodium sulfide, green chemistry

ID: J66-Y2015