Synthesis of mono- and bis-spirooxindole derivatives “on water” using double salt of aluminum sulfate–sulfuric acid as a reusable catalyst, By Khodabakhsh Niknam

Research

Title	Synthesis of mono- and bis-spirooxindole derivatives “on water” using double salt of aluminum sulfate–sulfuric acid as a reusable catalyst
Type	Article
Keywords	Double salt Bis-spirooxindoles On water Synthesis Catalyst
Journal	MOLECULAR DIVERSITY
DOI	10.1007/s11030-020-10091-5
Researchers	Esmali Ghaderi (Third researcher) , Khodabakhsh Niknam (Fourth researcher)

Abstract

The preparation of double salt of aluminum sulfate–sulfuric acid (Al4(SO4)6·(H2SO4)·24H2O) by the reaction of aluminum sulfate and sulfuric acid in water is described. Aluminum sulfate–sulfuric acid is characterized via some spectroscopic and microscopic techniques such as infrared spectroscopy (IR), X-ray diffraction spectroscopy (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) which corroborated the structure of the double salt. This double salt is soluble in water and insoluble in organic solvents. It was employed as a new catalyst for the synthesis of spirooxindole compounds on water with good to excellent yields. The double salt could be recycled and reused without appreciable loss of activity.