title: Ligand-free copper-catalyzed synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2-aminobenzothiazoles, and benzoxazoles.
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 can be recovered and recycled without loss of activity.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India.
authors.forename: Prasenjit
authors.initials: P
authors.lastname: Saha
authors.forename: Tamminana
authors.initials: T
authors.lastname: Ramana
authors.forename: Nibadita
authors.initials: N
authors.lastname: Purkait
authors.forename: Md Ashif
authors.initials: MA
authors.lastname: Ali
authors.forename: Rajesh
authors.initials: R
authors.lastname: Paul
authors.forename: Tharmalingam
authors.initials: T
authors.lastname: Punniyamurthy
mesh_terms: D001562:Benzimidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D001583:Benzoxazoles / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D001562:Benzimidazoles; D001583:Benzoxazoles; D008024:Ligands; D003300:Copper; C030973:cupric oxide