Synthesis of quinolines by a solid acid-catalyzed microwave-assisted domino cyclization-aromatization approach

A microwave-assisted solid acid-catalyzed synthesis of quinolines from anilines and cinnamaldehydes is described. Use of montmorillonite K-10 results in a one-pot process; the cyclization and oxidation steps readily take place in a domino approach. Reactions were completed in a matter of minutes and provided excellent yields. The efficient and ecofriendly catalyst and the convenience of the product isolation make this process an attractive alternative for the synthesis of these important heterocycles. (C) 2009 Elsevier Ltd. All rights reserved.