Premium
Multivalent Crown Ether Receptors Enable Allosteric Regulation of Anion Exchange in an Fe 4 L 6 Tetrahedron
Author(s) -
von Krbek Larissa K. S.,
Roberts Derrick A.,
Pilgrim Ben S.,
Schalley Christoph A.,
Nitschke Jonathan R.
Publication year - 2018
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/anie.201808534
Subject(s) - tetrahedron , allosteric regulation , chemistry , crown ether , tris , ammonium , ion , crystallography , receptor , stereochemistry , organic chemistry , biochemistry
Abstract We report a strategy for regulating the rate of internally bound anion exchange within an Fe 4 L 6 metal–organic tetrahedron through external coordination of tripodal tris(alkylammonium) cations. The cage features three flexible 18‐crown‐6 receptors at each of its Fe II vertices, facilitating strong tritopic interactions with tris(ammonium) cations to “cap” the vertices of the tetrahedron. This capping mechanism restricts the flexibility of the cage framework, thereby reducing the rate of anion exchange within its central cavity by 20‐fold. Thus, we demonstrate the first use of an externally bound multivalent effector to allosterically control internal guest binding in a molecular cage.