RESUMO
The self-assembled, hydrogen-bonded hexameric resorcin[4]arene capsule represents one of the most readily accessible host systems for the study of container catalysis. This assembly can stabilize cationic intermediates and transition states through cation-π interactions with the aromatic walls and several reactions have been successfully performed in its cavity. This highlight focuses mainly on the applications of this host system for the catalysis of cyclization reactions such as terpene cyclizations, intramolecular hydroalkoxylation and carbonyl-olefin metathesis.
RESUMO
Stereoisomeric complexes of an open-ended cavitand and its guest molecules (shown schematically) were detected, and complexes within caviplexes were introduced. Some control can be exerted on the stereoisomerism through methylation of the guest. The symbols "0" and "1" represent different ends of the guest molecule.
RESUMO
When outfitted with long alkyl chains, polycaps, capsules along a polymer chain, spontaneously organize themselves into a two-dimensional liquid crystalline phase. Further organization results from shearing or pulling the liquid crystalline samples, producing three-dimensional assemblies of micrometer-wide, infinitely long fibers (see schematic representation).
