Tetrathiafulvalene-Calix[4]pyrroles: Synthesis, Anion Binding, and Electrochemical Properties

详细信息    查看全文

• 作者：Kent A. Nielsen ; Won-Seob Cho ; Joë ; l Lyskawa ; Eric Levillain ; Vincent M. Lynch ; Jonathan L. Sessler ; and Jan O. Jeppesen
• 刊名：Journal of the American Chemical Society
• 出版年：2006
• 出版时间：February 22, 2006
• 年：2006
• 卷：128
• 期：7
• 页码：2444 - 2451
• 全文大小：272K
• 年卷期：v.128,no.7(February 22, 2006)
• ISSN：1520-5126

文摘

The syntheses of monotetrathiafulvalene-calix[4]pyrrole 5 and bistetrathiafulvalene-calix[4]pyrrole6, prepared from the acid-catalyzed condensation of monopyrrolo[3,4-d]tetrathiafulvalene (MPTTF, 7) withacetone in the presence of tripyrrane 8 and dipyrromethane 9, respectively, are described. Compound 5and the previously reported tetrathiafulvalene-calix[4]pyrrole 4 both adopt a 1,3-alternative conformation inthe solid state, as determined from X-ray crystallographic analysis. The anion binding properties of thetetrathiafulvalene-calix[4]pyrroles 5 and 6, as well as those of the parent meso-octamethylcalix[4]pyrrole(1), were investigated in acetone using ¹H NMR spectroscopic and isothermal titration calorimetry (ITC)techniques and, within the error limits of the methods, were generally found to give concordant results. Onthe basis of the results of the ITC studies carried out in 1,2-dichloroethane, increasing the number oftetrathiafulvalene units annulated to the calix[4]pyrrole system serves to enhance the anion binding affinitiessubstantially but at the price of lowered selectivity. Cyclic voltammetry (CV) studies, carried out in 1,2-dichloroethane, provided evidence of an anion-dependent electrochemical response with Cl^- and Br^- ions.This response was particularly dramatic in the case of the monotetrathiafulvalene-calix[4]pyrrole 5, with aE_max of -145 mV being seen after the addition of approximately 1 equiv of Cl^- ion.