Macrocyclic polyethers as probes to assess and understand alkali metal cation-π interactions

Cation-pi interactions of alkali metals with arenes have been known in the gas phase for two decades but solid-state structural data have become available only recently. The quest for solid-state evidence is described here. Complexation of Na+ and K+ by arene-terminated lariat ethers has provided important insights into the cation-pi interaction. (C) 2001 Elsevier Science B.V. All rights reserved.