Macrotricycles Featuring a π-Basic Tetrahedral Cavity: Preference for NH<sub>4</sub><sup>+</sup> Detected by Electrospray Ionization Mass Spectrometry
作者:Anne Lélias-Vanderperre、Jean-Claude Chambron、Enrique Espinosa、Peran Terrier、Emmanuelle Leize-Wagner
DOI:10.1021/ol070498a
日期:2007.8.1
Cation-pi interactions play an important role in biology. The title compounds are C-3-symmetric macrotricycles built from resorcinol, a pi electron-rich arene. They were prepared in up to 18% yield by intramolecular cyclization of 1,3,5-trisubstituted benzene tripods bearing pendant resorcinol groups, with methylene acetal bridges. Positive ESI-MS showed that these receptors recognize NH4+ over K+, and poorly respond to the large t-BuNH3+ cation, suggesting that they bind NH4+ intramolecularly, presumably via cation-pi interactions.