Guanidinium sulfonate

Fig. 12 An example of guanidinium-sulfonate superstructures. The fundamental interaction responsible for both robustness and flexibility is the charge-assisted (+)N-H---0( ) hydrogen bonding between the guanidinium cations and the sulfonate anions, which can be varied in shape and length [44]...

Figure 9.16 Ionic guanidinium sulfonate layer in pillared guanidinium disulfonates along with the two main types of architecture (a) pillared discrete bilayer and (b) simple brick (reprinted with permission from Section Key Reference American Chemical Society).

Figure 9.17 Variation of cavity volume with disulfonate length in guanidinium sulfonates.

Related to guanidinium sulfonates are analogous cation phosphonate structures which can adopt either pillared or zeotype structures. Recently novel tubular morphologies have also been discovered for both classes of compound which may have promise for improving porosity in these types of material. At present, like the guanidinium sulfonates, few phosphonates, are really porous and removal of the guest template generally leads to the collapse of the structures.15... 

Scheme 11. (a) Guanidinium sulfonate 2D layer (b) supramolecular isomers of guanidinium sulfonates (dependent on orientation of R on the sulfonate group, i.e. up or down). 

Fig. 16 a The quasi-hexagonal guanidinium sulfonate (GS) hydrogen-bonded array, b The shifted ribbon GS array [208]... 

A.M. Pivovar, M.D. Ward, T. Yildirim D.A. Neumann (2001). J. Chem. Phys., 115, 1909-1915. Vibrational mode analysis of isomotphous hydrogen-bonded guanidinium sulfonates with inelastic neutron scattering and density-functional theory. 

Fig. 6 An example of guanidinium-sulfonate superstructures. The fundamental interaction responsible for robustness and flexibility is the charge-assisted —H-. hydrogen bonding...

ORGANIC LAYERED SOLIDS AS HOSTS Guanidinium Sulfonates... 

The most extensively studied intercalation solids based upon weak interactions are the guanidinium sulfonate (GS) frameworks of Ward et These stractures are... 

Irradiation of 4,6-dimethyl-a-pyrone immobilized in a guanidinium-sulfonate-calixarene gives rise to a 4,6-dimethyl-Dewar-p-lactone, a carboxyl zwitterion and 1,3-dimethylcyclobutadiene, both in the solid crystalline state and in aqueous solution. Diarylmethyl carbocations have been generated within the cavities of non-protic zeolites (LiY, NaY, KY, RbY, CsY, and NaX) via laser-mediated decarboxylation of diarylacetic acids. 

Guanidinium-sulfonate interactions between the faces of a tetragonal Fe4Le coordination capsule 581 have been used for modulation of its guest exchange kinetics. A correlation between the concentration of guanidinium ions and the rate of the encapsulation process by Scheme 5.86 is described in [86]. 

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