Conjugated Belts and Nanorings with Radially Oriented p Orbitals

Undeterred by the propensity of trigonal carbon atoms to strive for planarity, synthetic chemists have recently succeeded in constructing novel macrocycles with inward-pointing p orbitals (see picture). Individual metal ions are too small to fill the cavity, but fullerenes are just the right size for some of these electron-rich, π-lined hosts.