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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Hercynite silica sulfuric acid: a novel inorganic sulfurous solid acid catalyst for one-pot cascade organic
Masoud Mohammadi1, Arash Ghorbani-Choghamarani2
1Department of Chemistry, Faculty of Science, Ilam University P. O. Box 69315516 Ilam Iran.
Abstract:
Herein, we delignated the synthesis of a novel inorganic sulfurous magnetic solid acid catalyst by the immobilization of an extremely high content of sulfuric acid functionalities on the amorphous silica-modified hercynite nanomagnetic core-shell via a simple method. Silica sulfuric acid (SSA) modified hercynite nanocomposite (hercynite@SSA) combines excellent recoverability and stability characteristics of hercynite (which can be regarded as a ferro spinel with Fd3m space group and cubic crystal structure) with the strong Brønsted acid properties of -SO3H groups. This nanomagnetic solid acid was found to be an efficient and facile strong solid acid catalyst for the synthesis of bis(pyrazolyl)methanes via two different one-pot multicomponent methodologies under green conditions. The hercynite@SSA catalyst shows excellent catalytic activity and reusability in the ethanolic medium among different solid acid materials. A plausible reaction mechanism is proposed for this synthesis.
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