Influence of Aromatic Substituents on the Supramolecular Architectures of Monoorganooxotin Drums

The reaction of n-BuSn(O)(OH) with various substituted benzoic acids affords hexameric organostannoxane drums, [n-BuSn(O)OC(O)R]6, where R = 2,6-(CH3)2−C6H3 (1), 4-CH3−C6H4 (2), 4-NH2−C6H4 (3) and 2-NH2−C6H4 (4). The central stannoxane motif (Sn6O6) is similar in all these compounds and is surrounded by six substituted benzoate groups. All the drums show an extensive supramolecular organization in the solid state. Accordingly, drum 1 forms a one-dimensional supramolecular assembly mediated by noncovalent interactions such as C−H···O and π···π interactions. Similarly, drums 24 form interesting three-dimensional supramolecular assemblies mediated by C−H···O, N−H···N, C−H···π, and π···π interactions in the solid state. The role of the peripheral aromatic substituents in determining the final course of the supramolecular assembly is discussed.