CuO Nanoparticles as an Efficient and Reusable Catalyst for the One-pot Friedlander Quinoline Synthesis

摘要

The quinoline ring system is presents in a number of natural and synthetic products often endowed with interesting pharmacological or physical properties. Quinoline derivatives are utilized as antimalarial, antitumor, and antibacterial agents. Due to their importance, the synthesis of quinolines attracted widespread attention. Despite quinoline usage in pharmaceutical and other industries, comparatively few methods for their preparation have been reported. The Friedlander annulation is one of the simplest and most straightforward methods for the synthesis of poly substituted quinolines. Modified methods employing acid catalysts such as lewis acids, bransted acids and ionic liquid have been reported for the quinoline synthesis. Although these approaches are satisfactory for a one-pot synthesis of quinolines, they suffer from at least one of the following drawbacks such as long reaction times, low yields of the products requiring stoichiometric amounts of catalysts, excess amounts of diketone compounds or use of additives. Such reactions under solvent-free condition have received more attention in comparison with their homogeneous counterparts, due to economical and environmental demands.