Synthesis of magnetic hollow mesoporous N-doped silica rods as a basic catalyst for the preparation of some spirooxindole-1,4-dihydropyridine derivatives

Abstract

In this study, magnetic hollow mesoporous N-doped silica rods were successfully prepared via the in-situ calcination of different amounts of diethanolamine in the presence of silica precursor. Doping of the nitrogen atoms in to silica rod structures was performed through a new method and the structure of obtained composite confirmed by X-ray photo electron spectroscopy (XPS), X-ray diffraction (XRD) analysis, elemental analysis, TEM, FESEM and elemental mapping methods. Comparison of the synthesized N-doped catalyst with the same sample without nitrogen atoms (mesoporous silica) showed the high basic characteristic. Furthermore, the efficiency of the prepared basic catalyst was investigated for the synthesis of some spirooxindole-1,4-dihydropyridine derivatives under green conditions. High efficient heterogeneous catalyst, short reaction times (compare with other reported methods) and green conditions are some advantageous of presented method.