A novel one-pot benzimidazole ring formation via a continuous flow selective reductive cyclization method

Balázs Szabó, F. Faigl, János Éles, István Greiner

Research output: Contribution to journalArticle

Abstract

A novel, simple and efficient laboratory scale continuous flow protocol has been elaborated for one-pot benzimidazole synthesis via a reductive cyclization method using the commercially available H-Cube Pro. Coupling with a stainless steel microreactor (4mL reactor volume), the acylation of o-nitroaniline was successfully joined in the hydrogenation step without any isolation or purification steps. This concept enabled a fully integrated process using a standard 5% Pt/C, sulfide catalyst for the reductive cyclization of 2-nitroacetanilide with quantitative yield. Compared with the previously reported batch processes, the present procedure facilitated efficient synthesis of a broad range of benzimidazole derivatives bearing functionalities sensitive to reductive cleavage and acidic conditions (10 compounds, 82 to >99% selectivity).

Original languageEnglish
Pages (from-to)1940-1944
Number of pages5
JournalCurrent Organic Chemistry
Volume22
Issue number19
DOIs
Publication statusPublished - Jan 1 2018

Fingerprint

Cyclization
Bearings (structural)
Acylation
Stainless Steel
Sulfides
Hydrogenation
Purification
Derivatives
Catalysts
benzimidazole
2-nitroacetanilide
2-nitroaniline

Keywords

  • Benzimidazole
  • Continuous flow
  • Heterocycles
  • One-pot
  • Reductive cyclization
  • Selective synthesis

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

A novel one-pot benzimidazole ring formation via a continuous flow selective reductive cyclization method. / Szabó, Balázs; Faigl, F.; Éles, János; Greiner, István.

In: Current Organic Chemistry, Vol. 22, No. 19, 01.01.2018, p. 1940-1944.

Research output: Contribution to journalArticle

Szabó, Balázs ; Faigl, F. ; Éles, János ; Greiner, István. / A novel one-pot benzimidazole ring formation via a continuous flow selective reductive cyclization method. In: Current Organic Chemistry. 2018 ; Vol. 22, No. 19. pp. 1940-1944.
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