Room temperature synthesis of benzimidazole derivatives using reusable cobalt hydroxide (II) and cobalt oxide (II) as efficient solid catalysts

MA Chari, D Shobha, T Sasaki

Index: Adharvana Chari, Murugulla; Shobha, Donthabhakthuni; Sasaki, Takehiko Tetrahedron Letters, 2011 , vol. 52, # 43 p. 5575 - 5580

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Citation Number: 70

Abstract

Here we demonstrate the synthesis of benzimidazoles through the coupling of 1, 2- phenylenediamine with aldehydes by using Co (OH) 2 and similarly CoO (II) as efficient solid catalysts in ethanol at room temperature. The Co (OH) 2 solid catalyst gave better yields (82–98%) in short reaction times (4–7h) than CoO (II) catalyst (80–94%, 6–9h). These commercially available cheap catalysts are more active than many reported expensive ...