5,10-Diiododibenzo[a,e]pentalene

The crystal structure and the improved synthesis of the title compound (1) are presented. Treatment of 5,10-disilyldibenzo[a,e]pentalenes (2a and 2b) with iodine chloride (ICl) readily provided 1 in good yields. Recrystallization from a dichloromethane/hexane solution afforded single crystals suitable for X-ray diffraction studies. In the packing structure, iodine···iodine interactions classified as type II halogen bonding were found, forming the zigzag I…I chains along the ac-plane.