engleski

Anion directed self-assembly of a flexible ligand into highly porous and symmetrical organic solids

It is very hard to imagine modern supramolecular chemistry without principles of anion binding.1 Despite all progress in this field, significant anion binding rate in this type of assembly is hard to achieve due to the properties of anions (e.g. low charge to radius ratio, variable geometry etc.).2 Anion binding is interesting because of its potential applications and roles in many biological systems and industrial processes, such as nuclear waste managment, molecular sensing, transport and recognition etc.3 There is a remaining open question: is it better to create a rigid molecule, complement to specific anion, or to create a simple flexible molecule which can adapt its conformation and respond to the anion demands? 4 Herein we describe a solid-state study of several supramolecular complexes based on a podand containing three potential binding sites, namely, N, N’ -3-azapentane-1, 5-bis[3-(1-aminoethylidene)-6-methyl-3H-pyran-2, 4-dione (L), and anions with various geometries and basicities. Since the assembly is highly anion specific, the occurrence of the complexes in systems with high concentrations of competing anions has been explored. In addition, the role of the solvent in structural stabilization will be also discussed. [1] S. O. Kang, R. A. Begum, K. Bowman-James, Angew. Chem. Int. Ed. 2006, 45, 7882– 7894. [2] P. D. Beer, P. A. Gale, Angew. Chem. Int. Ed. 2001, 40, 486– 516. [3] J. L. Sessler, E. Katayev, G. D. Pantos, Y. A. Ustynyuk, Chem. Commun. 2004, 1276– 1277. [4] J. W. Steed, Chem. Commun. 2006, 2637– 2649.

supramolecular chemistry; template synthesis; anion recognition

nije evidentirano