title: Supramolecular organization of calix[4]pyrrole with a methyl-trialkylammonium anion exchanger leads to remarkable reversal of selectivity for sulfate extraction vs. nitrate.
abstract: meso-Octamethylcalix[4]pyrrole (C4P) enhances sulfate selectivity in solvent extraction by Aliquat® 336N, an effect ascribed to the supramolecular preorganization and thermodynamic stability imparted by insertion of the methyl group of the Aliquat cation into the cup of C4P in its cone conformation.
authors.affiliation: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6119, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Borman
authors.forename: Radu
authors.initials: R
authors.lastname: Custelcean
authors.forename: Ben P
authors.initials: BP
authors.lastname: Hay
authors.forename: Nathan L
authors.initials: NL
authors.lastname: Bill
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Moyer