Nano-Fe3O4@ZrO2-H3PO4 as an Efficient Recyclable Catalyst for the Neat Preparation of Thiazole Derivatives in Ordinary or Magnetized Water

Background: Thiazoles have been a class of important synthetic heterocyclic compounds which are widely used in clinical therapy. These compounds exhibited biological activities such as antitumor, antifungal, antibiotic, and antiviral properties. Also, applications such as liquid crystals and cosmetic sunscreens have been found for these important structures. Methods: The purpose of this work is to identify the most suitable condition for the synthesis of some thiazole derivatives in the presence of nano-Fe3O4@ZrO2-H3PO4 as magnetically recyclable nanocatalyst that presented as n-FZSA in the presence of the two forms of water (ordinary or magnetized) as solvent. Results: The results showed that n-FZPA exhibited high catalytic activity towards the synthesis of thiazole derivatives, with the desired products being formed in high yields. The catalyst was easily recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Furthermore, this new catalytic method for the synthesis of thiazoles provides rapid access to the desired compounds in high yields in the presence of ordinary or magnetized water upon reflux condition following a simple work-up procedure, and avoids the use of harmful organic solvents. Final outcomes exhibited that magnetized water showed better yields in shorter reaction times at the same conditions. This method therefore represents a significant improvement over the methods currently available for the synthesis of thiazole derivatives. Conclusion: This new method provided some thiazole derivatives via the reaction of acyl chloride with ammonium thiocyanate, amino acides and alkyl bromides catalyzed by n-FZPA in high yields over short reaction time upon refluxing ordinary or magnetized water, following a facile work-up process. Totally, the magnetized water provided a better situation as solvent for this reaction. The catalyst is inexpensive and easily obtained, stable and storable. Also, easy magnetic separation makes this catalyst attractive in view of green chemistry and catalysis science.