Mechanism Improvement and Process Optimization of the One‐Pot Synthesis of 3.7‐Dinitro‐1,3,5,7‐Tetraazabicyclo[3,3,1]nonane from Urea.

As a key precursor in the preparation of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX), 3,7‐dinitro‐1,3,5,7‐tetraazabicyclo[3,3,1]nonane (DPT) prepared from urea by a modified one‐pot method has a bright future. On the basis of our previous work (Reaction Mechanism of One‐Pot Synthesis of Dinitro Pentamethylene Tetramine, Chinese Journal of Organic Chemistry 2010, 30 (3), 414–418.) [1], a novel intermediate 3‐nitro‐1,3,5,7‐tetraazabicyclo[3,3,1]nonane was captured and isolated, and the key reactive intermediate hexahydro‐1‐nitro‐1,3,5‐triazine was directly captured and confirmed by HPLC‐MS. Thus, a modified synthetic mechanism for DPT was elaborated, and based which DPT preparation process was optimized. [ABSTRACT FROM AUTHOR]