Ligand-free copper-catalyzed synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2-aminobenzothiazoles, and benzoxazoles.
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.
Saha
Prasenjit
P
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, India.
Ramana
Tamminana
T
Purkait
Nibadita
N
Ali
Md Ashif
MA
Paul
Rajesh
R
Punniyamurthy
Tharmalingam
T
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
D001562:Benzimidazoles; D001583:Benzoxazoles; D008024:Ligands; D003300:Copper; C030973:cupric oxide