Self-assembly of a novel functional molecule: 1,2,4,5-tetra(p-hydroxyphenyl)benzene

A new rigid tetraaryl-substituted benzene, 1,2,4,5-tetra(p-hydroxyphenyl)benzene (C30H22O4, TetHPB), has been synthesized. Its crystalline hydrate C30H22O4·2H2O (1) and the inclusion compound of its anions with the tetrapropylammonium cations, [(C30H21O4)2H]−·(n-C3H7)4N+ (2), have been prepared and characterized by single crystal X-ray diffraction. The results of the structural study show that the four peripheric para hydroxyl benzene rings of the TetHPB molecules twist around the aryl–aryl bonds and adopt an X-shaped configuration thus avoiding steric congestion. In the crystal structure of 1 hydrogen-bonded TetHPB chains are connected to a 3D architecture by hydrogen bonds mediated through the solvent water molecules and by C–H…π interactions. In compound 2, the TetHPB anions construct an anionic arrangement based on O–H…O hydrogen bonds. The resulting host contains cavities which accommodate the tetrapropylammonium cations, thus forming a channel-like inclusion compound. These results demonstrate that TetHPB molecules allow to construct hydrogen-bonded networks with cavities; co-crystallized water molecules may cooperate in the formation of these extended structures.