It is of some scientific interest as a stable derivative of the highly reactive antiaromatic pentalene by benzannulation.

[1] Aromatic dicationic salts can be obtained by reaction with antimony pentafluoride in sulfuryl chloride.

The dianion forms by reduction with lithium metal or deprotonation of 5,10-dihydroindeno[2,1-a]indene with two equivalents of butyllithium.

[4][5] The aromatic nature of the dianion has been confirmed by X-ray analysis.

[6] Another isomer of this compound exists called dibenzo[a,f]pentalene with one of the benzene rings positioned on the other available pentalene face.