A Simple and Green One-Pot Synthesis of 2-Arylbenzimidazoles from Alcohols Using MnO2/I2
- 1Department of Industrial and Engineering Chemistry, Institute of Chemical Technology – IOC Bhubaneswar, IIT Kharagpur Extension Centre, Mouza Samantpuri, Bhubaneswar, Odisha, India, 751013
- 2Department of Chemistry
- 3National Institute of Technology Puducherry
Abstract
A straightforward and green synthetic method has been developed to prepare functionalized 2-arylbenzimidazole derivatives from readily accessible starting materials (arylmethyl alcohols and o-phenylenediamines) via a two-step, one-pot reaction. In the first step, arylmethyl alcohols are oxidized using MnO2 (4-8 equiv.) under both solvent-free and toluene-mediated conditions. subsequently, the aromatic aldehyde undergoes a 10 mol% iodine-catalyzed condensation with o-phenylenediamine in toluene at 100 °C under open-air conditions, leading to the production of 2-substituted benzimidazoles. The one-pot direct conversion of benzyl alcohols to 2-arylbenzimidazoles proceeds efficiently, affording the desired benzofused imidazoles in good to excellent yields, up to 91%. The sustainable method exhibits broad substrate scope, tolerating a wide range of functional groups. Mechanistic studies support a plausible imine formation pathway, followed by cyclization and oxidative aromatization under open-air conditions. This work highlights the synthetic utility and potential of the developed green method for future applications in organic synthesis and medicinal chemistry.
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BibTeX
@misc{gat2026simple,
title = {{A Simple and Green One-Pot Synthesis of 2-Arylbenzimidazoles from Alcohols Using MnO2/I2}},
author = {Savita Gat and Selvam Vasanth and Jayshree Nandkumar Solanke and Vasudevan Dhayalan and Rambabu Dandela},
howpublished = {ChemRxiv},
year = {2026},
month = sep,
doi = {10.26434/chemrxiv.15008907/v1},
url = {https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008907/v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - A Simple and Green One-Pot Synthesis of 2-Arylbenzimidazoles from Alcohols Using MnO2/I2
AU - Savita Gat
AU - Selvam Vasanth
AU - Jayshree Nandkumar Solanke
AU - Vasudevan Dhayalan
AU - Rambabu Dandela
PY - 2026
DA - 2026/09/16
PB - ChemRxiv
DO - 10.26434/chemrxiv.15008907/v1
UR - https://chemrxiv.org/doi/full/10.26434/chemrxiv.15008907/v1
AB - A straightforward and green synthetic method has been developed to prepare functionalized 2-arylbenzimidazole derivatives from readily accessible starting materials (arylmethyl alcohols and o-phenylenediamines) via a two-step, one-pot reaction. In the first step, arylmethyl alcohols are oxidized using MnO2 (4-8 equiv.) under both solvent-free and toluene-mediated conditions. subsequently, the aromatic aldehyde undergoes a 10 mol% iodine-catalyzed condensation with o-phenylenediamine in toluene at 100 °C under open-air conditions, leading to the production of 2-substituted benzimidazoles. The one-pot direct conversion of benzyl alcohols to 2-arylbenzimidazoles proceeds efficiently, affording the desired benzofused imidazoles in good to excellent yields, up to 91%. The sustainable method exhibits broad substrate scope, tolerating a wide range of functional groups. Mechanistic studies support a plausible imine formation pathway, followed by cyclization and oxidative aromatization under open-air conditions. This work highlights the synthetic utility and potential of the developed green method for future applications in organic synthesis and medicinal chemistry.
ER -