2,6-Dimethoxy-9,10-anthraquinone

The title compound, C16H12O4, crystallizes with two half-molecules in the asymmetric unit, each of which is completed by a crystallographic inversion center. The two crystallographically independent molecules have almost the same geometry and are almost planar [maximum deviations = 0.018 (3) and 0.049 (3) Å]. They adopt a conformation in which the Cmethyl—O bonds are directed along the molecular short axis [C—C—O—C torsion angles of 179.6 (2) and 178.0 (2)°]. In the crystal, the molecular packing is characterized by a combination of a columnar stacking and a herringbone-like arrangement. The molecules form slipped π-stacks along the b axis, in which there are two kinds of columns differing from each other in their slippage. The interplanar distances between neighboring molecules are 3.493 (3) for one column and 3.451 (2) Å for the other.