anti-Tricyclo­[4.2.1.12,5]deca-3,7-diene-9,10-dione

The title compound, C10H8O2, is a precursor to an unusual bis-homoaromatic dication and to heterodiamantanes and other oxa-cage compounds. Two independent mol­ecules, each of which is situated on a center of symmetry, comprise the unit cell. Both mol­ecules are in nearly identical chair conformations