Metal organic nanocapsules

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

Although most substituted pyrogallol[4]arene capsules have quite reasonable stability based on their 72 hydrogen bond network, Atwood showed that they could be further stabilized by replacing the network with various metals. Atwood, Dalgamo, and coworkers explored these compounds extensively and found that only certain elements were appropriate to the formation of these metal organic nanocapsules, or MONCs [21]. One such metal was copper, which we used in developing a membrane-resident ion conductor as described later in this chapter. 

Early examples of both capsules and the metal organic nanocapsules were prepared from pyrogallol[4]arene that had relatively short side chains. A typical side chain is n-butyl or isobutyl, and solid-state structures have been reported for these capsules by several groups. Work in this area continues until today in several labs, but our interest in pyrogallol[4]arenes diverged from the capsule approach. 

The pyrogallol[4]arenes have shown remarkable properties. They are amphiphi-les even when their alkyl side chains are short. When their alkyl side chains are longer (eg, in the Cn range), they self-assemble into ion-conducting pores within bilayer manbranes. The alkyl side-chained pyrogallol[4]arenes can also form into previously known capsules, but these can entrap solvent molecules within then-chains. When converted into a metal organic nanocapsule, ion conducting activity... 

Dalgamo SJ, Power NP, Warren JE, Atwood JL (2008) Rapid formation of metal-organic nanocapsules gives new insight into the self-assembly process. Chem Commun 1539-1544... 

Recently, Atwood and coworkers reported a series of metal-organic analogs of multimeric nanocapsules based on resor-cin[4]arenes (76) and pyrogallol[4]arene units (77). These containers contain several metal atoms in the hydrogen-bonded seam connecting the capsule units and it was demonstrated that metal... 

Kouhi, M., Mohebbi, A., Mitzaei, M., and Peikari, M. (2013) Optimization of smart self-healing coatings based on micro/nanocapsules in heavy metals emission inhibition. Progress in Organic Coatings, 76, 1006-1015. 

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