Novel Magnetically Separable Sulfated Boric Acid Functionalized Nanoparticles for Hantzsch Ester Synthesis
Received: 24 February 2016
Accepted after revision: 18 March 2016
26 April 2016 (eFirst)
This article is dedicated to the memory of Mansour Sattari.
A novel, separable, solid-acid catalyst consisting of sulfated boric acid nanoparticles immobilized on a silica-coated magnetite support was prepared. This catalyst permits the preparation of dihydropyridine derivatives (Hantzsch esters) by condensation of an aldehyde with two equivalents of a β-keto ester in the presence of ammonium acetate. The catalyst can be recovered and recycled.
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