A Rapid Access to Novel and Known Benzimidazole Derivatives Using Silica Chloride as a Reusable Catalyst (original) (raw)
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silica boron sulfonic acid (SBSA) was easily prepared and used as a new and efficient solid acid catalyst for the synthesis of benzimidazole derivatives with high isolated yields. Various substituted benzimidazoles were synthesized by a combination of o-phenylenediamines and aldehydes in the presence of boron sulfonic acid in with good yields in water and under a mild reaction conditions. This method is also applicable for precursors such as: aromatic and unsaturated aldehydes and o-phenylenediamines.
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