Stacking Them High

See allHide authors and affiliations

Science  17 Aug 2001:
Vol. 293, Issue 5533, pp. 1225
DOI: 10.1126/science.293.5533.1225a

Molecular-scale wires have many potential applications in nanotechnology. Such wires may be assembled from molecular units by exploiting intermolecular interactions, such as metal-ligand bonds or hydrogen bonds. Benzene rings may also stack up to form the conductive backbone of a molecular-scale wire; substituents may then form an insulating sheath around this core. Unfortunately, the interactions between the benzene rings are relatively weak, and the resulting columnar structures are not very stable.

Bushey et al. have synthesized benzene rings with three amide substituents in alternate positions on the ring; the remaining three positions are taken up by various ether substituents. The resulting molecules form columnar structures that are stabilized by hydrogen bonds between the amide nitrogens and the ether oxygens of alternating rings in the column. The approach is versatile in that other functional groups could be placed on the outside of the column. Furthermore, the dipole moment should be amplified in the columnar stacks, which should prove useful in electro-optical and other applications. — JU

J. Am. Chem. Soc., 10.1021/ja0104148.

Navigate This Article