11‐octasubstituted pentacenequinonederivatives were prepared by the oxidation of 1,2,3,4,8,9,10,11‐octasubstituted pentacenes, which were synthesized by the double homologation method. Oxidation of the pentacenes was carried out with H5IO6 or air and DDQ. These octasubstituted pentacenequinones were converted into 1,2,3,4,6,8,9,10,11,13‐decasubstituted or 2,3,6,9,10,13‐hexasubstituted pentacenederivatives by the