Chiral supramolecular capsule by ligand promoted self-assembly of resorcinarene-zn porphyrin conjugate

Cavitand-Zn porphyrin conjugates self-assemble to give supramolecular (1 + 1) structures upon coordination of bifunctional ligands such as 4,4'-bipyridine and the like. The formation of the capsule depends on key structural factors, such as the size of the cavity, and the possibility of the onset of hydrogen bonds, π-π and π-cation interactions. The extension of this protocol to chiral bifunctional ligands, such as (+)-cinchonine and (-)-cinchonidine, and cinchona alkaloid derivatives, results in the achievement of supramolecular structures with chiral cavities, whose configuration is dependent on the asymmetry of the bound ditopic ligand. MM calculations, gave further insights into the plausible geometry of the structures. Copyright © 2008 Society of Porphyrins & Phthalocyanines.