Molecular geometry and crystal structure of 9-acetylanthracene

Abstract

The molecular geometry of 9-acetylanthracene has been established by X-ray diffraction analysis. The acetyl group is twisted out of the plane of the aromatic π-system by 88º. The intermolecular geometry in crystalline 9-acetylanthracene is characterized by head-to-tail pairs with an interplanar distance of 3.42 Å between parallel aligned anthracene moieties. Parallel adjacent molecules of 9-acetylanthracene deviate from perfect overlap by a long-axis shift of 1.35 Å, and a short-axis shift of 0.88 Å.