Synthesis of 5-Nitrotetrazolate via the Aqueous Oxidation of 5-Aminotetrazole

Abstract

The preparation of the important energetic precursor sodium nitrotetrazolate has long been plagued by safety and purity problems. The prevailing synthesis methods utilizing the Sandmeyer reaction proceed via sensitive, explosive intermediates and would be classified as a high-hazard process. In this work, we directly oxidize precursor 5-aminotetrazole to 5-nitrotetrazole in aqueous solution utilizing a heterogeneous titanium superoxide catalyst, skipping the sensitive intermediates inherent in the current industrial Sandmeyer route and providing a vastly safer process with a yield of 50−65%. The prepared sodium nitrotetrazole is of high purity and therefore is directly useful in the synthesis of the primary explosive DBX-1, which is a synthesis that is highly sensitive to impurities. The improved safety and excellent product purity demonstrates the superiority of our route.

A Facile Zinc(II) Chloride Assisted Desulfurization of High‐Nitrogen Heterocycles

“…Nitrogen rich heterocycles, in particular tetrazoles, are important to fields as diverse as pharmaceuticals [1] and energetic materials (propellants and explosives). [2] In the pharma industry 5-substituted tetrazoles are a bioisotere for the carboxylic acid group, [3] and 1-substituted tetrazoles are found in numerous drugs. [4] While the chemistry of 5-substituted-1-H tetrazoles is particularly well developed where the tetrazole ring is easily built up from a parent nitrile and an azide source, the preparation of 1-substituted tetrazoles is considerably less investigated.…”

“…Nitrogen rich heterocycles, in particular tetrazoles, are important to fields as diverse as pharmaceuticals [1] and energetic materials (propellants and explosives) [2] . In the pharma industry 5‐substituted tetrazoles are a bioisotere for the carboxylic acid group, [3] and 1‐substituted tetrazoles are found in numerous drugs [4] .…”

Thermal Risk Assessment of Sandmeyer Reaction from 5-Aminotetrazole (5-AT) to Hydronium Copper(II)-tris(5-nitrotetrazolate) trihydrate

“…In this process, neither of intermediates needed to be handled by an operator, and the purification step was no longer necessary. Although many methods have been researched to solve issues of prepare 5-NaNT, which was beneficial to simple synthesis technology and enhance the safety of production [15][16][17][18][19]. The other important question has been overcome, that was the safety of Sandmeyer reaction, many explodes have been reported in the paper.…”

Process Study on One-Pot Synthesis of DBX-1 with High Conversion Rate and Intrinsic Safety

“…have the disadvantages of high cost, long reaction time, low yield, etc., making it difficult to apply in practice (Table ). − Currently, the majority of laboratory synthesis and industrial production still use the synthesis process proposed by Von Herz in 1937, which uses hydronium copper­(II)-tris­(5-nitrotetrazolate) trihydrate (intermediate 1 ) as the intermediate. − …”