Coordination hexameric

PdF4 is the only stable palladium(IV) halide [18] (testimony to the oxidizing nature of palladium(IV)) and is a very moisture-sensitive diamagnetic red solid the structure is based on Pd6F24 hexameric units linked three-dimensionally. It has octahedrally coordinated palladium with two terminal (cis) fluorines and four bridging ones. Despite the absence of other tetra-halides, the complete series of PdX - exist (cf. Ir). 

Figure 3.67 Part of the hexameric [Pd(SPr )2]6 molecule showing square-planar coordination of palladium. (Reproduced with permission from Acta Crystallogr. Sect. B, 1968, 24, 1623.)...

Figure 7-18 Stereoscopic MolScript ribbon drawings of the B chains (A chains omitted) of (A) hexameric 2-zinc pig insulin. (B) A phenol complex of the same protein. Within each dimer the B chains are shaded differently. The Zn2+ ions are represented by white spheres and the coordinating histidine side chains are shown. Six noncovalently bound phenol molecules can be seen, as can several conformational differences. From Whittingham et al.B7 Courtesy of Peter C. E. Moody.

A hexameric Cu compound, in which each Cu atom is coordinated through the non-esterified sulfur and the nitrogen atom, was prepared from the ester of monophenyl dithiocarbamate after deprotonation of the nitrogen atom.54... 

Numerous metallomacrocycles self-assemble from their components giving species possessing various structures, for instance triangular shape [9.30,9.31] containing a cavity [9.32], which may include a guest molecule [9.33] square [9.34,9.35] or star like [9.36-9.39] shapes wheel-shaped or toroidal hexameric [9.40], octameric [9.41] or decameric [9.42,9.43] structures square [9.44,9.45] rectangular [9.46,9.47] or bent [9.48] boxes into which substrate molecules may bind [9.49,9.50] adaman-tanoid shape [9.51,9.52] with cation inclusion [9.51c], formally related to that of the spheroidal macrotricycle 21 catenane type [9.53]. Coordination species of dendri-mer or arborol nature have been constructed [7.61, 8.27, 9.54]. 

However, for hexameric alkyllithiums in hydrocarbon solution, bases can coordinate to form either a solvated hexamer (Eq. (9)) ... 

McKinlay, R. M., Thallapally, P. K., Atwood, J. L., Hexameric C-alkylpyrogallol[4]arene molecular capsules sustained by metal-ion coordination and hydrogen bonds. Chem. Commun. 2006, 2956-2958. 

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