Organic Chemistry Portal



Parallel Synthesis of a Library of Benzoxazoles and Benzothiazoles Using Ligand-Accelerated Copper-Catalyzed Cyclizations of ortho-Halobenzanilides

Ghotas Evindar and Robert A. Batey*

*Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6, Email:

G. Evindar, R. A. Batey, J. Org. Chem., 2006, 71, 1802-1808.

DOI: 10.1021/jo051927q

see article for more reactions


A general method for the formation of benzoxazoles and benzothiazoles via a copper-catalyzed cyclization of ortho-haloanilides is reported. Optimal conditions for cyclization used a catalyst combination of CuI and 1,10-phenanthroline as ligand. The mechanism is believed to proceed via an oxidative insertion/reductive elimination pathway through a Cu(I)/Cu(III) manifold. The rate of reaction of ortho-haloanilides follows the order I > Br > Cl, consistent with oxidative addition being the rate-determining step.

see article for more examples

proposed mechanism

Copper-Catalyzed Domino Annulation Approaches to the Synthesis of Benzoxazoles under Microwave-Accelerated and Conventional Thermal Conditions

R. D. Viirre, G. Evindar, R. A. Batey, J. Org. Chem., 2008, 73, 3452-3459.

Key Words

Benzoxazoles, Benzothiazoles

ID: J42-Y2006-610