Pd/C catalytic cyclopropanation of polycyclic olefins for synthesis of high‐energy‐density strained fuels.

Cyclopropane derivates are appealing to synthesis of high‐energy‐density fuels because of the high strained energy of the three‐numbered ring. The catalytic cyclopropanation of olefin with diazomethane is very effective to construct the carbocycle. The majority of the catalysts employed are nonrecyclable homogeneous compounds. Herein, we report cyclopropanation of polycyclic olefins catalyzed by heterogeneous Pd/C. The optimal cyclopropanation conditions were explored utilizing dicyclopentadiene as model substrate and a series of polycyclic olefins were cyclopropanated with high yield. Additionally, the catalyst has good recyclability and stability, as shown by characterizations as well as the fact that no inactivation happens after cyclopropanation. The synthesized cyclopropane derivates exhibit good fuel characteristics like high density (1.006–1.087 g/cm3), high volumetric net heat of combustion (42.58–46.45 kJ/cm3), good low‐temperature and combustion performance. This work shows industrial potential for cyclopropanation of polycyclic olefins with diazomethane. [ABSTRACT FROM AUTHOR]