Surface Modification and Enhanced Catalytic Interface in Bifunctional Montmorillonite for the Synthesis of Novel Thiazolo[3,2‐<i>a</i>]pyrimidine‐6‐Carboxylates

Abstract This study centers on the modification of montmorillonite (MMT) through the incorporation of pillaring agents, specifically ceria (CeO 2 ) and zirconia (ZrO 2 ), using a straightforward synthesis technique. The resulting catalyst is thoroughly characterized by employing various standard spectroscopic and electron microscopic methods to verify its structural and compositional integrity. Moreover, temperature‐programmed desorption (TPD) is utilized to assess and quantify the acidic properties of the catalyst. The modified MMT catalyst is then applied in the ultrasonic‐assisted one‐pot synthesis of novel thiazolo[3,2‐ a ]pyrimidine‐6‐carboxylates. This approach allowed for the efficient production of these compounds, which are subsequently characterized by 1 H NMR, 13 C NMR, and High‐Resolution Mass Spectrometry (HRMS) to confirm their structures. Additionally, the study elucidates the mechanistic role of ultrasonication in enhancing the synthesis process, highlighting the way sonic energy improves reactant dispersion, accelerates reaction rates, and facilitates high‐yield formation of the target heterocycles.