Star hexacarboxylate: Synthesis,crystal structure and luminescent properties of its terbium complex

A new star host, hexakis (carboxylphenyl-2-thiolmethyl)benzene (1H₆), has been synthesized by a simple one-step condensation procedure with the high yield. Crystal structure of the DMSO adduct 1H₆·6DMSO (2) reveals it to be rhombohedral crystal system, space group R-3, with a = b = 2.4129(2), c = 1.1576(3) nm, α= β = 90°, γ= 120°, ∨= 5.837(2) nm³, Z = 3. The six arms of side benzoic acid rings and the H-bonded DMSO molecules are located alternatively above and below the central benzene plane with “1,3,5-up/2,4,6-down” conformation. Terbium complex (Tb₂1)₂Py·9H₂O (3) was prepared in hot pyridine, which shows bright characterized Tb(III) emission with a longer lifetime and higher luminescent intensity than that of the corresponding terbium benzoate in solid state. These observations suggest that host 1 is a good antenna for sensitizing Tb^III emission.