Eco-friendly synthesis and characterization of a highly efficient heterogeneous catalyst for benzo[d]thiazole derivatives under mild condition

This research presents the development of two novel catalysts, CM and SB, derived from naturally abundant clay minerals, which, to the best of our knowledge, have not been previously utilized in organic chemical reactions. The CM catalyst is composed of a mixture of quartz, kaolinite, illite, and montmorillonite, while the SB catalyst consists of sodium feldspars (albite and orthoclase). The catalysts were characterized using a variety of techniques, including scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and energy-dispersive X-ray fluorescence. Their catalytic performance was tested in the synthesis of benzo[d]thiazole, using 2-aminothiophenol and various aldehyde derivatives. The results revealed high yields (83-94%) in a short reaction time (90-150 min), with ethanol identified as the optimal solvent for the reaction. Additionally, the optimal catalyst mass was found to be 16 mg, providing the highest yield efficiency. Notably, these catalysts demonstrated excellent recyclability, maintaining their catalytic activity over five consecutive cycles with minimal reduction in efficiency. These findings highlight the promising potential of these natural clay-based catalysts in sustainable and green organic synthesis, offering high yields, short reaction times, excellent recyclability, and alignment with the principles of green chemistry.