Cavitand ligand

LSs is the trithiolate cavitand ligand, l,3,5-tris((4,6-dimethyl-3-mercaptophenyl)thio)-2,4,6-tris(p-tolylthio)benzene(3-). 

The structure of the parent material in this study—due to its uniqueness with respect to its inequivalent chloride ions both as coordinated and lattice chlorides—represents yet still another example of a solid state copper imidazole material. Others include copper(II) perchlorate salts complexed with amines [10] and copper(I) imidazole complexes based on a cavitand ligand design [11], Copper(I) imidazole complexes have been... 

Figure 7.4 Cavitand ligands with four pyridyl (14) and pyridylethynyl (15) substituents at the apical position.

A different synthetic procedure to introduce cyanophenyl groups at the apical position (12c) was reported by Kobayashi et al. in 2004, together with the synthesis of the two new tetradentate cavitand ligands 14 and IS (Figure 7.4) [26]. 

Figure 7.10 Trimeric assemblies of bispyridyl cavitand ligands 39a-d.

Figure 7.13 Thioether-functionalized cavitand ligand and the corresponding homocage 43 and heterocage 44.

We therefore turned our attention to the self-assembly of neutral complexes, which are kinetically stable in solution, starting from the same cavitand ligands [57]. The use of cis-[ Pt(CH3CN)2Cl2] and cis-[Pt(DMSO)2Cl2] as metal precursors led to the formation of the trans complex 49 in both cases (Figure 7.21). The unexpected stereochemistry of the final product is the result of the cis-to-trans isomerization of the intermediate monofunctionalized complexes. 

Fig. 9 Design of cavitand ligands 31a-b and 33a-b and the self-assembly of cavitands to form metallo-supramolecular cages 32a-h and 34a-f...

Ugono O, Moran JP, Holman KT (2008) Closed-surface hexameric metal-organic nanocapsules derived from cavitand ligands. Chem Commun 1404... 

A very efficient one-pot synthesis of the octahedral hexacavitand caging hgand 20 with a cavity volume of approximately 1700 has been performed in [26] by Scheme 2.9 through 18-component imine condensation of 6 aldehyde-functionalized cavitand ligand syntones and 12 terminal diamine linkers, followed by the reduction of a Schiff-base cage intermediate with NaBH4. 

Effects of remote chiral centers of the resorci-narene and cavitand ligand syntones on encapsulated guests have been observed in [127] for their hybrid supramolecular capsules 448-454 giving 1 1 cage complexes with encapsulated neutral guest 202 by Scheme 3.120. These distal effects are additive or subtractive, depending on the relative configurations of the chiral elements. 

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