Experimental

R factor = 0.043; wR factor = 0.126; data-to-parameter ratio = 13.4. In the title molecule, C23H18O3, the dihedral angle between the two naphthalene ring systems is 80.44 (4). The mean plane of the bridging carbonyl C—C ( O)—C group makes a torsion angle of 68.55 (17) with the naphthalene system of the 2,7-dimethoxynaphthalene unit and a torsion angle of 9.01 (19) with the naphthalene ring system of the naphthoyl group. In the crystal, a weak C—H O hydrogen bond occurs between the carbonyl O atom and an H atom of the naphthalene ring in the 2,7-dimethoxynaphthalene unit of a symmetry-related molecule. Related literature For electrophilic aromatic aroylation of naphthalene deriva-tives, see: Okamoto & Yonezawa (2009); Okamoto et al. (2011). For the structures of closely related compounds, see: Kato et al. (2010); Muto et al. (2011, 2012); Nakaema et al. (2008); Tsumuki et al. (2011)