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Preparation of benzimidazole N-oxides by a two-step continuous flow process

A continuous flow process for the synthesis of nitrobenzimidazole N-oxides from 2,6-dinitrochlorobenzene and amines or amino acids is reported. The process, performed in a two-step sequence, is faster than previously reported batch processes and avoids some of the isolation and purification steps.

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Fabrizio Politano is thankful to Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina, for a PhD fellowship and to Bec.Ar – Fulbright Commission, for an exchange fellowship.

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Correspondence to Nicholas E. Leadbeater.

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Published in Khimiya Geterotsiklicheskikh Soedinenii, 2016, 52(11), 952–957

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Politano, F., Buján, E.I. & Leadbeater, N.E. Preparation of benzimidazole N-oxides by a two-step continuous flow process. Chem Heterocycl Comp 52, 952–957 (2016).

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  • benzimidazoles
  • N-oxides
  • cyclization
  • flow chemistry
  • green chemistry
  • nucleophilic aromatic substitution