New norbornane derivatives based on diene condensation of spiro2.4hepta-4,6-diene with methylenecyclopropane and methylenecyclobutane have been synthesized. The obtained adducts were modified both by palladium-catalyzed hydrogenation and by cyclopropanation, accompanied by the formation of an additional strained cycle in the molecule structure. The obtained hydrocarbon compounds demonstrate high values of combustion heat and density in a wide temperature range. The specific impulse calculated values of the majority of the synthesized compounds exceed similar characteristics of the JP-10 reference fuel by 4–11 s. The first obtained dispirocyclopropane-(1,6′)-tricyclo[3.2.1.0octane-(8′,1′′)-cyclopropane] has a specific impulse exceeding that of boctane. The obtained results can serve as a fundamental basis for further expansion the field of new high-energy fuel synthesis and the new highly effective types of rocket fuels introduction to the market.
V. A. Zigarev (Thu,) studied this question.