title: Ammonium ion binding with pyridine-containing crown ethers.
abstract: Dipyrido[24]crown-8 (DP24C8) has been synthesized and shown to form [2]pseudorotaxanes spontaneously with dibenzylammonium ions. These complexes, which have been demonstrated by (1)H NMR spectroscopy to form faster in solution than when the macrocyclic polyether is dibenzo[24]crown-8 (DB24C8), are also stronger than their DB24C8 counterparts. One of the [2]pseudorotaxanes has been used to construct a [2]rotaxane (see above) comprising a dumbbell-shaped component based on a dibenzylammonium ion which is encircled by a DP24C8 macrocycle and terminated by (triphenylphosphonium)methyl stoppers.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095-1569, USA.
authors.forename: T
authors.initials: T
authors.lastname: Chang
authors.forename: A M
authors.initials: AM
authors.lastname: Heiss
authors.forename: S J
authors.initials: SJ
authors.lastname: Cantrill
authors.forename: M C
authors.initials: MC
authors.lastname: Fyfe
authors.forename: A R
authors.initials: AR
authors.lastname: Pease
authors.forename: S J
authors.initials: SJ
authors.lastname: Rowan
authors.forename: J F
authors.initials: JF
authors.lastname: Stoddart
authors.forename: A J
authors.initials: AJ
authors.lastname: White
authors.forename: D J
authors.initials: DJ
authors.lastname: Williams