The indole side chain of tryptophan as a versatile π-donor

J Hu, LJ Barbour, GW Gokel

Index: Hu, Jiaxin; Barbour, Leonard J.; Gokel, George W. Journal of the American Chemical Society, 2002 , vol. 124, # 37 p. 10940 - 10941

Full Text: HTML

Citation Number: 44

Abstract

Single-armed, 15-and 18-membered lariat ether receptor systems having indolylethyl side arms bind Na+ and K+ in the ring. The indole residue serves as a π-donor to the ring-bound cation. Whether the five-or six-membered ring interacts most directly with Na+ or K+ depends on whether the sidearm is attached to indole's 3-or 5-position. This suggests that structural as well as electronic factors are important in π-complexation of alkali metal ...