Supramolecular Organization Using Multiple Secondary Bonding Interactions

Treatment of 1,4-bis(2-mercaptoethyl)benzene (1) or 1,4-bis(2-bromoethyl)benzene (2) with excess SbCl3 affords new one-dimensional and two-dimensional supramolecular coordination networks. Compound 1·2SbCl3 is stabilized solely by Sb···Cl, Sb-π, and Sb···S secondary bonding interactions (SBIs), providing an unusual example of Sb(III) and a thiol interacting through an SBI rather than a strong antimony thiolate bond. 2·2SbCl3 is stabilized by Sb···Cl, Sb···Br, and Sb-π SBIs. Both compounds have higher melting points than that of SbCl3. The crystal structures of 1·2SbCl3 and 2·2SbCl3 have been determined by single crystal X-ray diffraction methods.