Control of Face-to-Face π−π Stacked Packing Arrangement of Anthracene Rings via Chalcogen−Chalcogen Interaction:  9,10-Bis(methylchalcogeno)anthracenes

Crystal packing structures of 9,10-dimethoxyanthracene (1), 9,10-bis(methylthio)anthracene (2), and 9,10-bis(methyltelluro)anthracene (3) were revealed by X-ray crystallographic analysis as models for the molecular ordering of acenes. Compound 1 is arranged in a herringbone packing motif similar to anthracene. In contrast, compound 2 is arranged by face-to-face π−π stacking with S−S interactions. The anthracene columns of 2 formed by face-to-face π−π stacking are parallel to each other and are linked by the S−S interactions to self-assemble into a 2-D network sheet. The resulting 2-D network sheets are packed parallel to each other in an offset manner. Compound 3 is arranged by face-to-face π−π stacking with Te−Te interactions, concomitant with Te−π interactions, to produce a 2-D network sheet similar to 2. Thus, the chalcogen−chalcogen interaction plays an important role in the face-to-face π−π stacking arrangement of 9,10-bis(methylchalcogeno)anthracenes 2 and 3. In contrast to 2, the neighboring 2-D network sheets of 3 are packed to each other with large tilt angle (γ-motif). The self-assembling cyclophane-network structure of {[2(3)·2(Ag+)]·(NO3 -)}·(NO3 -) is also described.