title: (E)-2-Meth-oxy-9-(2-meth-oxy-9H-xanthen-9-yl-idene)-9H-xanthene.
abstract: The title compound, C28H20O4, was synthesized by a bimolecular Zn-HCl reduction in glacial acetic acid using the meth-oxy-substituted xanthone as a starting material. The crystal structure shows that the 2,2'-meth-oxy-bixanthenyl-idene unit is an E-type conformation anti-folded conformer. The mol-ecule lies on an inversion center. The meth-oxy group is almost coplanar with the attached benzene ring, with a C-O-C-C torsion angle of 179.38 (14)°.
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei 230026, People's Republic of China.
authors.forename: Xiang-Yu
authors.initials: XY
authors.lastname: Tian
authors.forename: Qin-Hua
authors.initials: QH
authors.lastname: Song
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