Sonogashira Coupling Reaction Catalyzed By Cu(Ⅱ)-NaY Zeolite

In the past decades, zeolites have achieved great success as industrial catalysts in petroleum chemistry. Also, their application in organic synthesis has aroused much research interest recently. However, knowledge on zeolite catalysis is much limited for most synthetic chemists, which restricts, to a large extent, further application of zeolites as efficient catalysts in the area of synthetic organic chemistry.Aiming to apply zeolites as heterogeneous catalysts in organic synthesis and to further study the mechanisms involved, we conducted the research described in this thesis, which consists of two parts.In the first chapter, the basic background on zeolite catalysis was introduced. Moreover, the applications of zeolites as efficient catalysts in organic synthesis were summarized. In the second chapter, Sonogashira coupling reaction catalyzed by Cu(â…¡)-NaY zeolite under heterogeneous conditions has been achieved for the first time. Sonogashira coupling reaction is the most straightforward method for the synthesis of substituted alkynes. Pd or Pd/Cu salts are generally utilized as efficient catalysts for this reaction. With the growing shortage of noble metals and the revival of copper catalysis, many efforts have been dedicated to develop copper-only catalytic systems to realize Sonogashira coupling reaction. Most reports of these copper-only systems are Cu(â… )-catalysis and only few papers deal with Cu(â…¡)-catalysis. Furthermore, applications of Cu(â…¡) salts as heterogeneous catalysts for Sonogashira coupling reaction are quite limited. Accordingly, we present herein, for the first time, that Cu(â…¡)-NaY zeolite is an effective catalyst for Sonogashira coupling reaction, which possesses the advantage of ligand-free and palladium-free catalysis. A preliminary investigation on the mechanism involved in this process has also been performed.