The present invention relates to methods for synthesizing energetic compounds and intermediates thereof. Specifically, the present invention relates to methods for synthesizing adamantanes and intermediates that are useful in such synthesis. Synthesized intermediates are useful in the synthesis of bicyclic and tricyclic substituted adamantanes. Examples of various intermediates are: acyclic 2-nitromalonaldehyde intermediates, 2,6,9-tri-substituted-4,8-dinitro-2,6,9-triazabicyclo[3.3.1]nona-3,7-dienes and 2,6-dinitro-4,8,9,10-tetra-aza-4,8,9,10-tetra-substituted adamantanes. Intermediates synthesized according to the methods of the present invention are useful toward the synthesis of tetraaza-adamantanes, which can serve as precursors to potentially superior new high-energy-density compounds (HEDCs).