First Examples of Ternary Lanthanide 2,2′‐Diphenyldicarboxylate Complexes: Hydrothermal Syntheses and Structures of Lanthanide Coordination Polymers of 2,2′‐Diphenyldicarboxylic Acid and 1,10‐Phenanthroline

In the four new lanthanide coordination polymers {[La 2 (2,2′‐dpdc) 3 (phen)(H 2 O)]·2H 2 O} n ( 1 ), [Eu 2 (2,2′‐dpdc) 3 (phen)(H 2 O) 2 ] n ( 2 ), {[Ln 2 (2,2′‐dpdc) 3 (phen) 2 (H 2 O) 2 ]·4H 2 O} n [Ln = Tb ( 3 ), Yb ( 4 )] (2,2′‐dpdc = 2,2′‐diphenyldicarboxylate, phen = 1,10‐phenanthroline), prepared by hydrothermal synthesis, the 2,2′‐dpdc dianion affords tetradentate, pentadentate, and hexadentate coordination modes. Complex 1 is a two‐dimensional network of infinite 1‐D chains assembled through π−π interactions, with nine‐ and ten‐coordinate La 3+ , and arranged in wave‐like layers. In 2 , Eu 3+ possesses nine‐ and ten‐coordinate geometries bridged by 2,2′‐dpdc ligands to give a 3‐D structure. The isomorphous complexes 3 and 4 , in which Tb 3+ and Yb 3+ ions are both nine‐coordinate, have two‐dimensional structures of 1‐D zigzag chains stacked via hydrogen bonds and π−π interactions of phen molecules. The high‐resolution emission spectrum of 2 shows two Eu 3+ ion sites, which is consistent with the results of the X‐ray crystal structure analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)