Metal-Free Catalytic Oxidation of Urazoles under Mild and Heterogeneous Conditions via Combination of Ammonium Nitrate and Catalytic Amounts of Silica Sulfuric Acid

A. Ghorbani-Choghamarani^a,, M.A. Zolfigol^b,, M. Hajjami^b and S. Mallakpour^c

^aDepartment of Chemistry, Faculty of Science, Ilam University, P.O. Box 69315516, Ilam, Iran
^bFaculty of Chemistry, Bu-Ali Sina University, P.O. Box 6517838683, Hamadan, Iran
^cOrganic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, Iran

Highly efficient production of 4-substituted-1,2,4-triazole-3,5-diones from urazole derivatives using ammonium nitrate and silica sulfuric acid (SiO₂-OSO₃H), as a cheap and nontoxic catalyst, in the presence of wet SiO₂ (50% w/w) under mild and heterogeneous conditions is reported. The process presented here is operationally simple, environmentally benign and produces high yield.

Keywords: Urazole, Bis-urazole, Triazolinedione, Ammonium nitrate, Silica sulfuric acid

Metal-Free Catalytic Oxidation of Urazoles under Mild and Heterogeneous Conditions via Combination of Ammonium Nitrate and Catalytic Amounts of Silica Sulfuric Acid

A. Ghorbani-Choghamarania,*, M.A. Zolfigolb,*, M. Hajjamib and S. Mallakpourc

aDepartment of Chemistry, Faculty of Science, Ilam University, P.O. Box 69315516, Ilam, Iran bFaculty of Chemistry, Bu-Ali Sina University, P.O. Box 6517838683, Hamadan, Iran cOrganic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, Iran

A. Ghorbani-Choghamarani^a,, M.A. Zolfigol^b,, M. Hajjami^b and S. Mallakpour^c

^aDepartment of Chemistry, Faculty of Science, Ilam University, P.O. Box 69315516, Ilam, Iran
^bFaculty of Chemistry, Bu-Ali Sina University, P.O. Box 6517838683, Hamadan, Iran
^cOrganic Polymer Chemistry Research Laboratory, Department of Chemistry, Isfahan University of Technology, Isfahan, Iran