Multivalent Crown Ether Receptors Enable Allosteric Regulation of Anion Exchange in an Fe4L6 Tetrahedron

L.K.S. von Krbek, D.A. Roberts, B.S. Pilgrim, C.A. Schalley, J.R. Nitschke – 2018

Precise control over guest uptake and release in molecular cages is critical for applications in catalysis and chemical separations. Here we report a strategy for regulating the rate of internally-bound anion exchange within an FeII4L6 metal-organic tetrahedron through external coordination of tripodal tris(alkylammonium) cations. The cage features three flexible 18-crown-6 receptors at each of its FeII vertices, facilitating strong tritopic interactions with tris(ammonium) cations to ‘cap’ the vertices of the tetrahedron. This vertex-capping mechanism restricts the flexibility of the cage framework, which reduces the rate of anion exchange within its central cavity 20-fold when tris(ammonium) cations are bound externally. Thus, we demonstrate the use of an externally-bound multivalent effector for allosteric control over internal guest binding in a molecular cage.

Titel
Multivalent Crown Ether Receptors Enable Allosteric Regulation of Anion Exchange in an Fe4L6 Tetrahedron
Verfasser
L.K.S. von Krbek, D.A. Roberts, B.S. Pilgrim, C.A. Schalley, J.R. Nitschke
Datum
2018
Kennung
10.1002/anie.201808534
Zitierweise
Angew. Chem. Int. Ed., 2018, 57, 14121-14124; Angew. Chem., 2018, 130, 14317-14320
Art
Text
dfg_logo