Supramolecular cages

Synthesis of a Large Metallo-Supramolecular Cage from a Cavitand-Terpy Building... 

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...

One of the first formal definitions of a supramolecular cage-like host-guest structure was proposed by... 

Hartshorn. C.M. Steel. P.J. Self-assembly and x-ray structure of a ten-component, three-dimensional metallo-supramolecular cage. Chern. Commun. 1997. 541-542. 

In the field of self-assembly of molecular components to generate defined structures which can be used as molecular devices, structural and functional information must be contained at the molecular level. The approach described in 1993 in Lehn s group was to use two complementary components a mesa 5,15-diuracil-substituted porphyrin and an alkyl triaminopyrimidine.- The interaction between the hydrogen-bonded sites of both components led in large part to a bis-porphyrin supramolecular cage structure 6 as evidenced by proton NMR and fluorescence and electrospray mass spectroscopy as well as by vapour phase osmometry (Figure 7). 

Figure 7. Supramolecular cage-like compound 6 formed through 12 H bonds between two porphyrins covalently linked to 5-alkyluracil recognition groups, and two alkyltriaminopyrimidine units.

Substitution-inert, redox- and photo-active ruthenium(ii) complexes based on 2,2, 6, 2"-terpyridine ligands (see Fig. 8) were self-assembled into discrete supramolecular cages via coordination to palladium(n)... 

C.M. Drain, R. Fischer, E.G. Nolen, and J.M. Lehn (1993). Self-assembly of a bisporphyrin supramolecular cage induced by molecular recognition between complementary hydrogen-bonding sites. J. Chem. Soc. Chem. Commun. 243-245. 

A bis-porphyrin supramolecular cage is obtained by self-assembly of two prophyrin components bearing uracil type units that interact through hydrogen bonding with two complementary triaminopyrimidine units (Figure 5) [26]. 

Supramolecular Cage Formed by Self-Assembly of Trimeric Zinc... 

SUPRAMOLECULAR CAGE FORMED BY SELF-ASSEMBLY OF TRIMERIC ZINC COMPLEX WITH TRITHIOCYANURIC ACID... 

For the construction of more robust supramolecular cages in aqueous solutions at neutral pH, we replaced the CA of (14) + with trithiocyanuric acid (TCA Scheme 3.6). An expected advantage of TCA over CA was that the three imide deprotonation constants of TCA (pK values of 5.1, 8.2, and 11.7) were about two orders of magnitude lower than those for CA (pK s of 6.9, 10.9, and >12). For this reason, the trianionic TCA might stabilize at near-neutral pH. 

Sumby, C. J. Fisher, J. Prior, T. J. Hardie, M. J. 2006. Tris(pyridylmethylamino)cyclotriguaiacylene cavi-tands An investigation of the solution and solid-state behaviour of metallo-supramolecular cages and cavitand-based coordination polymers. Chem. Eur. J., 12 2945-59. 

Garrison, J. C. Panzner, M. J. Custer, P. D. Reddy, D. V. Rinaldi, P. L. Tessier, C. A., and Youngs, W. J. (2006). Synthesis and Characterization of a Trigonal Bipyramidal Supramolecular Cage Based upon Rhodium and Platinum Metal Centers. Chem. Commun., 4644-4646. 

Fleming JS, Mann KLV, Carraz C-A, Psillakis E, Jeffery JC, McCleverty JA, Ward MD (1998) Anion-templated assembly of a supramolecular cage complex. Angew Chem Int Ed 37 1279-1281... 

Han M, Hey J, Kawamura W, Stalke D, Shionoya M, CleverGH (2012) An inclusion complex of hexamo-lybdate inside a supramolecular cage and its structural conversion. Inorg Chem 51(18) 9574-9576... 

Custelcean and Wu groups independently reported tripodal tris(3-pyridylurea) receptor 38e, which assembled with metal sulfate salts MSO4 (M = Mn, Zn, Co, Mg, etc.) to afford supramolecular cages encapsulating S04 anion via multiple H-bonds in a 3D structure held by second-sphere coordination (Fig. 5.30) [82, 83]. 

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