Ligand-free copper-catalyzed synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2-aminobenzothiazoles, and benzoxazoles

P Saha, T Ramana, N Purkait, MA Ali…

Index: Saha, Prasenjit; Ramana, Tamminana; Purkait, Nibadita; Ali, Md. Ashif; Paul, Rajesh; Punniyamurthy, Tharmalingam Journal of Organic Chemistry, 2009 , vol. 74, # 22 p. 8719 - 8725

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Citation Number: 223

Abstract

The synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2- aminobenzothiazoles, and benzoxazoles is described via intramolecular cyclization of o- bromoaryl derivatives using copper (II) oxide nanoparticles in DMSO under air. The procedure is experimentally simple, general, efficient, and free from addition of external chelating ligands. It is a heterogeneous process and the copper (II) oxide nanoparticles ...