ZnO-loaded mesoporous silica (KIT-6) as an efficient solid catalyst for production of various substituted quinoxalines

Conventional homogeneous and microporous heterogeneous catalysts for quinoxalines production from diamines and diketones usually suffer from difficult separation or harsh reaction conditions. Here, we demonstrate the production of various substituted quinoxalines using ZnO nanoparticle-loaded, highly ordered, mesoporous silica KIT-6 materials as solid catalysts in room temperature. The results show that the KIT-6-130-10Zn sample (aged at 130 degrees C and containing 10 wt% ZnO) effectively produces quinoxalines up to the maximum of 99%. We propose that the enhanced performance of the ZnO-loaded KIT-6 materials resulted from the homogeneous distribution of ZnO nanoparticles, along with the KIT-6's high specific surface area and large pore sizes. (C) 2016 Elsevier B.V. All rights reserved.