Dimeric Molecular Capsules under Redox Control

摘要

The design and self-assembly of molecular capsules is a very active topic of research in modern chemistry.A well-established methodology for the assembly of these supramolecular structures relies on the formation of kinetically stable,hydrogen-bonded dimers between two calix[4]arenes,each functionalized with four urea groups on its upper rim.The groups of Rebek and Bohmer have independently shown that two molecules of tetraphenylurea calix[4]arenes(similar to 1,but with different aliphatic chains in the lower rim)interact head-to-head to form a robust seam of hydrogen bonds between the four urea groups in each of the calixarene upper rims,giving rise to a dimer with S_8 symmetry.