Compound 4

(3-(6,6,6,6,6-Pentafluoro-6λ⁸-hexa-1,3,5-triyn-1-yl)bicyclo[2.2.0]hex-2-ene-1,2,4-triyl)tris(trimethylsilane)

From: A Diels–Alder super diene breaking benzene into C₂H₂ and C₄H₄ units