Guest exchange dynamics

Davis AV, Eiedler D, Seeber G, Zahl A, Van Eldik R, Raymond KN (2006) Guest exchange dynamics in tm MiLe tetrahedial host. J Am Chem Soc 128(4) 1324-1333... 

Figure 26.17 Dynamical processes for molecular information and expression in the cases of protein (upper) and steroidal molecules (lower), (a) A molecule as an information carrier, (b) a molecular architecture based on folding or assembly, (c) a host-guest complexation, and (d) a guest exchange reaction.

The question of guest exchange in inclusion compounds received little attention, despite that fact that such processes are important for sensing and catalysis based on inclusion. However, a number of host-guest systems with organic and metal-containing hosts that entrap volatile guests were recently studied.The host l,l,6,6-tetraphenyl-2,4-diyne-1.6-diol H) forms inclusion compounds with tetrahydrofuran (THF), and thiophene (THIO), and we analyzed the dynamics of the reaction ... 

Caira, M.R. Nassimbeni, L.R. Toda, F. Vujovic D. Inclusion by a diol host compound Structure and dynamics of volatile guest exchange. J. Chem. Soc., Perkin Trans., 2 2001, 2119-2124. 

X-ray crystallography provides the clearest structural evidence of the often-subtle intermolecular interactions. Combination of solution-state methods (NMR spectroscopy, mass spectrometry) and soUd-state methods (X-ray structure analysis) is necessary for an overall understanding of the host-guest behavior. In the case of self-assembled NRs, mechanisms of guest inclusion, guest exchange, and host-guest interactions are not simple, due to the dynamic, flexible nature of self-assembled NRs [13]. 

Solvent molecules within the hexameric capsule can be displaced by sizable quaternary ammonium salts, and dissociation of at least one resorcinarene molecule from the hexamer is required for guest exchange. More details about the dynamic process of this assembly at nano- and micromolar concentrations were acquired using... 

Szabo T, Hilmersson C, Rebek J Jr (1998) Dynamics of assembly and guest exchange in the tennis ball. J Am Chem Soc 120(24) 6193-6194... 

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