Orthorhombic and Monoclinic 2,3,7,8‐Tetramethoxythianthrene: Small Structural Difference–Large Lattice Change

Abstract

Merely the change of the solvent for the crystallization of the title compound leads to different crystal modifications. In the orthorhombic crystals (from n-hexane) a methoxy group is twisted out of the C6 plane (see structure). In the monoclinic crystals (from diisopropyl ether) all four methoxy groups lie in the plane of the C6 rings.