Synthesis of C-14-labelled octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) for use in microcosm experiments

To monitor the biodegradation of explosives in microcosm experiments, carbo n-14 labelled substrates such as C-14-HMX were needed. Many synthetic route s were evaluated to identify the best synthesis of C-14-HMX with high yield and minimal radioactive waste. To synthesize C-14-HMX, acetylation of labe lled hexamethylenetetramine (C-14-HMTA) was done yielding 3,7-diacetyt-1,3, 5,7-tetraazabicyclo-[3.3.1]-nonane (C-14-DAPT) which was nitrated to obtain 1,5-diacetyloctahydro-3,7-dinitro- 1,3,5,7-tetrazocine (C-14-DADN) in one step. Nitrolysis of C-14-DADN was achieved using a mixture of 100% nitric a cid and phosphorus pentoxide to yield C-14-HMX. The synthesis of this carbo n-14 labelled HMX was optimized first using cold starting materials and the n conducted with labelled compounds. This synthesis represents the best way of preparing high purity C-14-HMX with a high yield.