title: Localizing Perturbations of the Racemic Equilibria Involving Dipicolinate-Derived Lanthanide(III) Complexes.
abstract: Helical D3 tris(4-amino-2,6-pyridine-dicarboxylate)terbium(III) and europium(III) complexes, which form a racemic equilibrium in aqueous solution, were prepared to study their secondary coordination sphere interactions with chiral amino acids. These interactions were probed using a combination of circularly polarized luminescence (CPL) and 13C NMR spectroscopy. The results indicate that, regardless of the interaction between the chiral molecule and the complex, without an accessible hydrogen-bond donor on the associating molecule, perturbation of the racemic equilibrium cannot occur. A generalized conclusion is established that indicates that the mechanism of chiral recognition by tris(dipicolinate)lanthanide(III) complexes is similar across a variety of analogous ligands.
authors.affiliation: Department of Chemistry, San José State University, San José, California, USA.|Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, IL.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry, San José State University, San José, California, USA.|Department of Chemistry, Stanford University, Stanford, CA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Ingram
authors.affiliation: Department of Chemistry, San José State University, San José, California, USA.
authors.forename: Gilles
authors.initials: G
authors.lastname: Muller
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002942:Circular Dichroism; D056831:Coordination Complexes / Q000737:chemistry; D005063:Europium / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry; D008024:Ligands; D049449:Luminescence; D009942:Organometallic Compounds / Q000737:chemistry*; D010848:Picolinic Acids / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D056831:Coordination Complexes; D028581:Lanthanoid Series Elements; D008024:Ligands; D009942:Organometallic Compounds; D010848:Picolinic Acids; C000609711:tris(4-amino-2,6-pyridine-dicarboxylate)terbium; D005063:Europium; C030614:picolinic acid
keywords: D3 lanthanide complexes; Pfeiffer effect; circularly polarized luminescence; secondary coordination sphere; supramolecular chemistry