Dual-buckybowl Buckycatcher

A new molecular receptor for buckminsterfullerene contains two concave, bowl-shaped polycyclic aromatic hydrocarbon components that, unlike earlier C₆₀ receptors, embrace the C₆₀ molecule through "pure" concave-convex π-π interactions (J. Am. Chem. Soc. 2007, 129, 3842). The resulting 1:1 inclusion complex (shown) forms dark red crystals and provides the first experimental evidence of the robustness and importance of π-π interactions between the convex surface of a buckyball and the concave surface of a buckybowl, according to chemist Andrzej Sygula of Mississippi State University and coworkers. Unlike some previously reported molecular tweezers for C₆₀, the new C₆₀H₂₈ buckycatcher contains no heteroatoms or polar substituents that would enable it to bind to a fullerene via other types of interactions. Such receptors may be able to distinguish between different fullerenes and thus allow them to be separated, Sygula speculates.