Selective Oxidation of Heterocyclic Amines

ABSTRACT: New energetic materials are needed for use in explosives and propellants that have a very powerful energy release yet are insensitive to handling. Safer materials that also allow development of lighter weight, longer range missiles and higher performance explosives are needed. One class of such compounds is materials based on furazan heterocycles. While some furazans are too energetic, others have very attractive properties but are difficult or unsafe to make. To address this challenge, a synthetic method development program is proposed for the challenging selective oxidation of one amine of a diaminofurazan based compound called DAAzF to give the amino nitro compound ANAzF. New and current oxidants to such transformations will be trialed in a relatively high through put effort using microwave assisted organic synthesis with low to high temperature control. A much greater reaction space will thus be examined in terms of oxidant type, temperature, pressure, pH, reactant ratios and more to identify suitable conditions. Care will be taken to develop scalable methods, and LCMS will be used to follow progress of the reactions and determine mass balance. The end result will be a robust, general method that gives acceptable, reproducible yields in a scalable process that can be further scaled and expanded to other substrates in Phase II. BENEFIT: Successful completion of this program will provide a general method for preparing new, energetic materials of interest. The ability to prepare these new materials should be a useful tool in the development and testing of new, low sensitivity but high energy propellants and explosives. The method may also be useful in preparing pharmaceuticals and other chemicals.