Document Type: Original Research Article


Department of Chemistry, University of North Bengal, Darjeeling734013, India



Small amount of Zn dust and NaHSO3 was utilized to efficiently synthesize benzimidazole derivatives via one pot reductive cyclocondensation process in water medium at 100oC temperature. Very good to excellent yields in reasonably short reaction times, high atom economy and usage of readily available starting material, operational simplicity and easy workup are the fundamental features of this protocol.

Graphical Abstract


  • One potreaction
  • Chemoselective reductive cyclisation reaction.
  • Aqueous medium.
  • Shorter reaction time.
  • Easy reaction set-up.
  • Inexpensive, easily available reagent, easily separable by simple filtration.
  • Mild reaction condition.


Main Subjects


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Hridoydip Ranjan Dasgupta, Suvodip Mukherjee, Pranab Ghosh, One Pot Reductive Synthesis of Benzimidazole Derivatives from 2-Nitro Aniline and Aromatic Aldehydes Using Zn/NaHSO3 in Water Medium, Prog. Chem. Biochem. Res., 4(1) (2021) 57-67.

DOI: 10.22034/pcbr.2020.245413.1126