New Examples of Metal Coordination Architectures of 4,4′‐Sulfonyldibenzoic Acid: Syntheses, Crystal Structure and Luminescence

Seven metal–organic coordination polymers, namely [Cd(sfdb)(phen) 2 ] n · 2 n H 2 O ( 1 ), [Cd(sfdb)(bpy) 2 ] n · n H 2 O ( 2 ), [Cu(sfdb)(phen)(H 2 O)] n · 0.5 n H 2 O ( 3 ), [Zn(sfdb)(bpy)(H 2 O)] n · 0.5 n CH 3 OH ( 4 ), [Cd(sfdb)(quin)] n ( 5 ), [Cd 3 (sfdb) 2 (Hsfdb) 2 (phen) 2 ] n ( 6 ), and [Cd(sfdb)(bpy)] n ( 7 ) [H 2 sfdb = 4,4′‐sulfonyldibenzoic acid, phen = 1,10‐phenanthroline, quin = 2,2′‐biquinoline, bpy = 2,2′‐bipyridine] have been synthesized according to the principles of crystal engineering and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction analyses. Compounds 1 – 3 form 1D zigzag chains. Two phen ligands chelate to one cadmium atom in 1 , which is rare in similar polymers, while two 2,2′‐bpy ligands coordinate one cadmium atom in 2 . The zigzag chains in 3 propagate in two different directions (rotated by 75°) that are assembled by supramolecular forces into an intriguing three‐dimensional network. Complexes 4 and 5 form square‐wave‐like 1D chains, although the results indicate a transformation of 2,2′‐bpy into quin during the course of the hydrothermal synthesis of compound 5 . Compound 6 is a 1D grid‐chain based on a linear trinuclear unit, and compound 7 shows a 1D double chain containing 28‐membered rings with sfdb 2– ligands as bridges. Weak hydrogen bonding and intra‐ and/or intermolecular π ··· π stacking contacts in compounds 3 – 7 link the discrete 1D chains into high‐dimensional supramolecular structures. The sfdb 2– ligand displays multiple coordination modes in these seven complexes. Complexes 1 , 2 , and 4 – 7 show blue photoluminescence at room temperature. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)