A C-C bonded 5,6-fused bicyclic energetic molecule: exploring an advanced energetic compound with improved performance.

A C-C bonded amino-nitro pyrazole (7) and its ring-expansion product (9) have been synthesized and characterized. The synthetic route to 9 proceeds in several steps from the commercial substrate diethyl oxalate and acetone. The process was found to be straightforward, practical and easily scalable. Both of these structures were confirmed by single crystal X-ray diffraction. Compound 9 with a high density (1.85 g cm-3) at room temperature, excellent thermal stability (Td: 315 °C), good detonation performance and low sensitivity to impact and friction has potential as a high-temperature energetic material.