A SAFE AND SCALABLE PROCESS FOR THE SYNTHESIS OF MELT-CAST EXPLOSIVE 1-METHYL-3,5-DINITRO-1<i>H</i>-1,2,4-TRIAZOLE

Abstract

An improved and safe process for the production of 1-methyl-3,5-dinitro-1H-1,2,4-triazole, a promising melt-cast explosive to replace TNT, is described starting from dicyandiamide and methylhydrazine. The key step in our procedure is generation of target compound by catalytic oxidation of 3,5-diamino-1-methyl-1,2,4-triazole nitrate with hydrogen peroxide at 65 to 70°C. The main advantage of our procedure is the use of modified catalytic oxidation system and improved reagent addition method, which enabled proper control of the reaction exotherm in a 2-l reactor. After solvent  extraction, 1-methyl-3,5-dinitro-1H-1,2,4-triazole was obtained in up to 92.5% purity (HPLC) with 43% overall yield. An improved modification of 1-methyl-3,5-dinitro-1H-1,2,4-triazole with lower melting point was prepared, using carboxymethylcellulose sodium salt as a surfactant.