Synthesis of novel 6-(substituted benzyl)imidazo[2,1-b][1,3]thiazole catalyzed by polystyrene-supported palladium(ii) ethylenediamine complex

the polymer-supported palladium(ii) ethylenediamine complex, [ps-en-pd(ii)], is a highly active catalyst that could be used for the sonogashira coupling reaction between an aryl iodide and 2-amino-3-(2-propynyl)-1,3-thiazolium bromide, 3. this heterogeneous palladium catalyst is efficient, stable, and recyclable. reaction of compound 3 with various aryl iodides, 4a-f in the presence of the [ps-en-pd(ii)] complex leads to the production of the 6-(substituted benzyl)imidazo[2,1-b][1,3]thiazoles 5a-f.