Coordination cages sphere

Knots and Ravels, Self-Assembly of Coordination Cages and Spheres, Self-Assembly of Coordination Chains and Helices, Self-Processes, and Zeolitelike Metal-Organic Frameworks (ZMOFs) Design, Structure, and Properties, Supramolecular Materials Chemistry). 

Fig. 13.5 Coordination cages 15 and 16 obtained from TC4A, Co , and alkali hydrogen phosphates. Polyhedron Co, green sphere P, orange Na, blue K, yellow Cl ( 2014 American Chemical Society)...

Most tin(II) compounds display structures with a trigonal pyramidal coordination. This is of course to be expected as the tin atom is in the first place electrophilic in order to complete its outer electron configuration (cf. Chapter 5 and 6). To illustrate the resemblance of this geometry between ionic and molecular compounds, the structure of NH4SnF3 (5) 31) is compared with that of the cage compound (Me3CN)3(Me3A10)Sn4 (6) 32). The coordination sphere of the tin atom is the same in 5 and 6 (for the complete structure of 6 see Sect. 6.5) ... 

On the basis of kinetic studies, a mechanism for the radical oxidation of thioether with 36 has been proposed and is indicated in Scheme D ". The key step involves the formation of a radical cation-anion pair within the solvent cage. The presence of the pic ligand in the coordination sphere of the metal reduces the electrophilicity of the peroxo complex, thus allowing the competitive radical process to take place. 

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