Mellitic anhydride

Mellitic anhydride, the anhydride of mellitic acid, is an organic compound with the formula C₁₂O₉.

Mellitic anhydride is an oxide of carbon (oxocarbon), like CO₂, CO, and C₃O₂. It is a white sublimable solid, apparently obtained by Liebig and Wöhler in 1830 in their study of mellite ("honey stone"); they assigned it the empiric formula C₄O_3. The substance was properly characterized in 1913 by H. Meyer and K. Steiner. It retains the aromatic character of the benzene ring.