An Efficient Method for the Oxidation of Urazoles Under Mild and Heterogeneous Conditions

Abstract

A combination of inorganic acidic salts or silica gelsupported inorganic acids and sodium nitrite in the presence of wet SiO₂ was used as an effective oxidizing agent for the oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogenous conditions in good yields. Silica gel supported nitric acid and ceric ammonium nitrate (CAN) are also capable of effecting these oxidations in the absence of sodium nitrite in moderate to good yields. Mg(HSO₄)₂ is a superior to all the aforementioned reagents in convenience, yield and purity of the isolated triazolinediones.