A Halogen-Bonding-Based Heteroditopic Receptor for Alkali Metal Halides

Abstract

A new heteroditopic receptor for alkali metal halides has been designed and synthesized. It is comprised of a well-established motif for cation binding and a motif for halogen-bonding-based anion recognition processes. The single-crystal X-ray structure of the complex between the heteroditopic receptor and sodium iodide is reported. Thanks to the cooperativity of metal coordination and the strong I-...I halogen bonding, the ion pair is fully separated. The boosting effect of the binding of the anion through halogen bonding on the coordination of the cation by the receptor has been proved also in solution by NMR experiments. The selectivity of the new heterotopic receptor toward different alkali metal halides has been tested by ESI mass experiments.

Commemorating Two Centuries of Iodine Research: An Interdisciplinary Overview of Current Research

“…[18] The interaction of the most important iodine-containing biomolecule, the thyroid hormone thyroglobulin, with its receptors and the enzyme catalyzing its deiodination are considered to involve C À I···O = C [19] and C À I···Se À C (selenocysteine) [20] halogen bonds, respectively. In the field of supramolecular receptors for the formation of iodide complexes, there are now host-guest systems in which the iodide is bound through halogen bonding to a receptor appended with monoiodoperfluorophenyl groups, [21] in addition to those featuring N À H···I [22] and (triazole) C À H···I hydrogen bonds, and interactions with soft Lewis acids such as Hg in mercuracarborands. [23] …”

The quest for a molecular capsule assembled via halogen bonds

“…The C-pentyltetra(3-pyridyl)cavitand 2 and the calix [4]arene B were synthesized according to literature procedures 23,24 and isolated as white crystalline solids (see 60 Supporting Information). The non-covalent combination of the two modules was realized by adding the cavitand 2 (0.006 g, 0.0053 mmol) dissolved in 5mL of ethanol to a solution of calix [4]arene B (0.010 g, 0.0052 mmol) in 5 mL of the same solvent.…”

Zweihundert Jahre Iodforschung: ein interdisziplinärer Überblick über die derzeitige Forschung

“…[18] Es wird angenommen, dass an der Wechselwirkung des wichtigsten iodhaltigen Biomoleküls, des Schilddrüsenhormons Thyroglobulin, mit seinen Rezeptoren und dem Enzym, das seine Desiodierung katalysiert, Halogenbrücken der Typen C-I···O=C [19] und C-I···Se-C (Selenocystein) [20] beteiligt sind. Auf dem Gebiet supramolekularer Rezeptoren für die Bildung von Iodidkomplexen gibt es jetzt Wirt-Gast-Systeme, in denen Iodid über Halogenbrü-cken an einen Rezeptor mit Monoiodperfluorphenylgruppen gebunden ist [21] [zusätzlich zu denen mit N-H···I- [22] und (Triazol)C-H···I-Wasserstoffbrücken], sowie Wechselwirkungen mit weichen Lewis-Säuren wie Hg in Mercuracarboranden. [23] 4.…”