Preparation and characterization of 4-aminopyridine-functionalized zeolite-HY and application as a basic nanocatalyst in the synthesis of polyhydroquinolines

Combining inorganic and organic material is of interest for various applications, including catalysis, separation, and adsorption agents [1-4]. For catalysis, many kinds of organic acid and alkali were functionalized on various support materials such as amine compound-MCM-41, amine compound-SBA-15, carboxylic acid MCM-41, carboxylic acid-SBA-15,[5] and sulphonic acid-SBA-15 [6]. Zeolitic material, a crystalline aluminosilicate mineral, was more interesting than silica for functionalized support due to its large surface area, high chemical and thermal stability, and pore diameter that is selective to small organic molecules. Moreover, zeolite Y had a great density of silanol groups (Si-OH), potentially allowing a high density of functional groups to be attached. 1,4-dihydropyridyl compounds have various pharmaceutical and biological activities [7]. Thus development of a simple and efficient method for preparation of PHQ derivatives is an active research area, and there is a scope for further improvement involving milder and less hazardous reaction conditions. In this study, the preparation and characterisation of a basic catalyst with functionalized pyridine moiety on zeolite HY was introduced. The zeolite HY was functionalized with 4-aminopyridine compound and its catalytic activity was investigated in the synthesis of polyhydroquinoline derivatives.