ZnO nanoparticles embedded in SBA-15 as an efficient heterogeneous catalyst for the synthesis of dihydropyrimidinones via Biginelli condensation reaction

A new ZnO@SBA-15 nanocomposite material has been fabricated by an "in situ" generation of ZnO NPs on SBA-15 support. The as-synthesized nanocomposite material was fully characterized with various spectroscopic techniques and their catalytic activity was tested for the synthesis of a diverse range of dihydropyrimidinones (DHPMs) and thione derivatives via Biginelli condensation reaction. The catalytic efficiency of ZnO@SBA-15 nanocomposite was far superior with a remarkably lower catalyst loading and shorter reaction time compared to unsupported ZnO nanoparticles. The catalyst was recycled for minimum of four times without significant loss in its catalytic activity. Moreover, a tentative catalytic cycle for the reaction is also proposed. (C) 2017 Elsevier Inc. All rights reserved.