... Volume: Page: ... Figure 1 Dicyclopenta[a,e]pentalene 1 and dicyclopenta[a,f]pentalene 2 ... Diene-diyne 16 (300-mg scale) was stirred with 9 mol % of Co 2 (CO) 8 and irradiated with a Q-Beam MAX MILLION 100 W xenon spotlight 51 for 72 h at 50−55 °C under an ...