The synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2-aminobenzothiazoles, and benzoxazoles is described via intramolecularcyclization 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
A one step synthesis of functionlized N-acylanthranilamidevia Pd-catalyzed carboxamidation of o-halo substituted N-phenylamide consisting of isocyanideinsertion followed by oxidation of the imine intermediate has been achived successfully. Furthermore, at elevated temprature (160oC) the Pd-catalyzed tandem reaction afforded functionlized quinazolin-4-one in a single step without the isolation of
widely used in preparative organic syntheses. As copper production has recently exceeded a yearly amount of 20 million tons, using minerals instead of pure copper compounds can lower the need for such processes and can lead to more economical and environmentally friendly procedures. Such a method is the subject of our present study in which the preparation of 2-substituted benzoxazoles and benzothiazoles