Bipyrrole-Strapped Calix[4]pyrroles: Strong Anion Receptors That Extract the Sulfate Anion

Journal Article · Wed Jan 01 00:00:00 EST 2014 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja5086996· OSTI ID:1162081

Kim, Sung Kuk ^[1]; Lee, Juhoon ^[1]; Williams, Neil J ^[2]; Lynch, Vincent M. ^[1]; Hay, Benjamin ^[2]; Moyer, Bruce A ^[2]; Sessler, Jonathan L. ^[3]

---

1. University of Texas at Austin
2. ORNL
3. University of Texas

Cage-type calix[4]pyrroles 2 and 3 bearing two additional pyrrole groups on the strap have been synthesized. Compared with the parent calix[4]pyrrole (1), they were found to exhibit remarkably enhanced affinities for anions, including the sulfate anion (TBA+ salts), in organic media (CD2Cl2). This increase is ascribed to participation of the bipyrrole units in anion binding. Receptors 2 and 3 extract the hydrophilic sulfate anion (as the methyltrialkyl(C8-10)ammonium (A336+) salt)) from aqueous media into a chloroform phase with significantly improved efficiency (>10-fold relative to calix[4]pyrrole 1). These two receptors also solubilize into chloroform the otherwise insoluble sulfate salt, (TMA)2SO4 (tetramethylammonium sulfate).

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1162081
• Journal Information: Journal of the American Chemical Society, Vol. 136, Issue 42; ISSN 0002--7863
• Country of Publication: United States
• Language: English