Reversible Anion Exchange and Sensing in Large Porous Materials Built from 4,4'-Bipyridine via [pi]...[pi] and H-Bonding Interactions

• Published in: Inorganic chemistry Vol. 47; no. 12; pp. 5122 - 5128
• Main Authors: Qiu, Yongcai, Liu, Zhihui, Li, Yinghua, Deng, Hong, Zeng, Ronghua, Zeller, Matthias
• Format: Journal Article
• Language: English
• Published: 16.06.2008
• Subjects: Anion exchanging; Derivatives; Detection; Formations; Immersion; Porous materials; Single crystals; Transition metals
• ISSN: 0020-1669
• DOI: 10.1021/ic702366t

Two unusual d super(10) compounds, [Zn sub(2)(bipy) sub(3)(H sub(2)O) sub(8)(CIO sub(4)) sub(2)(paba) sub(2)][middot ]2( bipy)-4H sub(2)O (1) and [Cd sub(2)(bipy) sub(4)(H sub(2)O) sub(6)(ClO sub(4)) sub(2)(paba) sub(2)][middot ](b ipy)[middot]5H sub(2)O (2) (bipy = 4,4'-bipyridine, paba = p-aminobenzoate), were obtained from reaction of the metal salts, bipy and paba in an EtOH/H sub(2)O mixture. The bipy ligands in the two compounds exhibit two new modes of coordinating to transition metal ions, resulting in the formation of large porous frameworks. Immersion of single crystals of 1 in an aqueous solution of NH sub(4)PF sub(6) results in the formation of its hexafluorophosphate derivative 3 as shown by single crystal diffraction. Immersion of crystals of 3 in NaClO sub(4) regenerates 1. Furthermore, compound 1 also shows interesting anion sensing properties in an EtOH/H sub(2)O mixture.