A Computational Study of Reaction Routes of 1,3,3‐trinitroazetidine (TNAZ) Synthesis

Abstract

This study performs simulation modeling of the synthesis of 1,3,3-trinitro azetidine (TNAZ), a high-energy compound. Based on the experimental nitromethane and 1,3-dihalo-2-propanol raw material methods in the latest literature, we suggest reasonable reaction mechanisms. Using quantum mechanical theory, i.e., electronic density functional theory (DFT) B3LYP/6-31G(d,p) in the Gaussian 09 program, we have completed optimization work for all species in related reaction stages and obtained energy barrier data, which are used to identify the most feasible reaction pathways. Nitromethane has been used to react with formaldehyde through an ionic-type transition to produce 2,2-dinitro-1,3-propandiol, followed by reaction with hydrogen bromide to produce 1,3-dibromo-2,2-dinitro propane, then further react with a tertiary amine to produce 1-tertiary amino-3,3-dinitro azetidine, and subsequently nitrate to obtain TNAZ. Substituent effects of some atomic groups have been found during synthesis modeling, and a total activation energy of 1386.6 kJ/mol needs to be conquered in order to complete the reaction. Furthermore, from synthesis modeling using the 1,3-dihalo-2-propanol raw material method, the suggested reaction routes could be bromination of glycerol to 1,3-dibromo-2-propanol, followed by reaction with nitromethane to undergo amination, and further cyclization, oxidation, oximization, and nitration in sequence to produce the target product TNAZ. An overall 1163.5 kJ/mol energy barrier needs to be overcome in this part of the computation.