Macrocyclic, Dinuclear Zinc(<scp>II</scp>)‐Directed Self‐Assembly with Pyridine, 2,2′‐Bipyridine and 2‐Methylquinoline: μ²‐OH Bridging Bi‐Macrocyclic Complexes and Hydrogen‐Bond‐Supported Donor‐Acceptor Complexes

Abstract

Abstract Two macrocyclic dinuclear zinc( II ) complexes ( 1a and 1b ) have been self‐assembled in the presence of pyridine and 2,2′‐bipyridine, respectively, to form μ 2 ‐OH‐bridged bimacrocycles with a Zn 4 O 4 cavity through coordination bonding. The X‐ray structural analysis reveals that both compounds { 2a : [Zn 4 L a 2 (OH) 2 ] 2 (ClO 4 ) 2 ; 2b : [Zn 4 L b 2 (OH) 2 ] 2 (ClO 4 ) 2 } have an open‐mouthed sandwich‐like structure with π−π interactions between parts of two phenyl rings to strengthen two hydroxyl groups connecting the metal atoms in the same direction of the macrocycle. Furthermore, nonclassical C−H ··· Cl intermolecular interactions have been observed in the crystal of 2b . In addition, the reaction of 1a with quinoline derivatives has yielded novel hydrogen‐bond‐supported donoracceptor complexes { 3a : [Zn 2 L a (H 2 O) 2 (C 10 H 9 N) 2 ](ClO 4 ) 2 }. The crystallographic study of the complex containing 2‐methylquinoline indicates that two 2‐methylquinoline molecules are linked to two coordinating water molecules above and below the macrocyclic framework through O−H ··· N hydrogen bonds. The 2‐methylquinoline plane interacts in a face‐to‐face fashion with the phenyl ring of adjacent macrocyclic frameworks, forming an ordered arrangement where one macrocycle and two 2‐methylquinolines are arrayed alternately with almost the same separation. The interplanar distance mentioned before is ca. 3.6 Å. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2003)