Preparation and application of kaolin-based magnetic nanocatalyst for the synthesis of 4H-pyrimido[2-1-b] benzothiazole derivatives

4H-Pyrimido[2,1-b]benzothiazole derivatives are an important category of fused heterocycles due to their wide range of potential biological activities such as anti-tumor,anti-allergic,anti-inflammatory, anticonvulsant,and antimicrobial activity [1, 2]. Kaolin is a rock rich in kaolinite clay, which is very cheap and abundant and has diverse uses in the industry. Kaolinite is a clay mineral, part of the group of industrial minerals, with the chemical composition Al2Si2O5(OH)4. It is a layered silicate mineral, with one tetrahedral sheet of silica (SiO4) linked through oxygen atoms to one octahedral sheet of alumina (AlO6) octahedral [3]. In this investigation, Kaolin/TiCl4/Fe3O4 was synthesized and characterized by FT-IR, XRD, TGA, FESEM and EDS techniques. 4H-Pyrimido[2,1-b]benzothiazole was prepared via three-component reaction of 2-amino-benzothiazole, aldehyde, and β- ketoester in the presence of Kaolin/TiCl4/Fe3O4. The structure of products were confirmed by FT-IR, 1H NMR and 13C NMR spectra.Reusability, eco-friendly and thermal stability are some advantages of this no expensive efficient catalysts. Short reaction times, high yields, simplicity of operationand easy work up are some of advantages of this method.