@article {4954,
	title = {Nuclear magnetic resonance studies of helical dipyrromethene-zinc complexes},
	journal = {Organic Letters},
	volume = {2},
	number = {9},
	year = {2000},
	note = {ISI Document Delivery No.: 309XRTimes Cited: 27Cited Reference Count: 16},
	month = {May},
	pages = {1315-1318},
	type = {Article},
	abstract = {Analysis of helical chirality within dinuclear dipyrromethene-Zn(II) complexes has been achieved with the use of H-1 NMR spectroscopy. The use of AgFOD and chiral lanthanide shift reagents gives fully resolved resonances attributable to two diastereomeric helical complexes.},
	keywords = {chirality, LIGANDS, NMR, RESOLUTION, SHIFT-REAGENTS},
	isbn = {1523-7060},
	url = {<Go to ISI>://000086795200036},
	author = {Thompson, A. and Dolphin, D.}
}
@article {3926,
	title = {Cationic lanthanide complexes of N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetic acid (H(2)bped)},
	journal = {Inorganic Chemistry},
	volume = {36},
	number = {7},
	year = {1997},
	note = {ISI Document Delivery No.: WQ490Times Cited: 22Cited Reference Count: 51},
	month = {Mar},
	pages = {1316-1321},
	type = {Article},
	abstract = {A series of monocationic lanthanide complexes containing the ligand N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetate(2-) (bped(2-)) have been prepared and isolated as either the hexafluorophosphate or perchlorate salts. The complexes have been characterized by H-1 and C-13 NMR, +LSIMS, IR, and elemental analysis. Complex formation constants have been measured in water at 25 degrees C (mu = 0.16 M (NaCl)). log K (Ln(bped)](+)) (log K([Ln(bped)(OH)])): Ln = La, 10.81 (0.06); Ln = Nd, 11.99 (1.45); Ln = Gd, 12.37 (2.10); Ln = Ho, 12.31 (3.00); Ln = Yb, 13.32 (4.43). The stability constants for [M(bped)](+) increase from La(III) to Nd(III), plateau to Ho(III), and increase again to Yb(III), while the formation constants for [Ln(bped)(OH)] increase almost linearly with atomic number. The solution structures of the [Ln(bped)](+) complexes have been probed by multinuclear NMR (H-1, C-13, O-17) studies, and these indicate only one isomer present in solution; this isomer has 2-fold symmetry and is rigid at 20 degrees C on the NMR time scale. O-17 NMR studies of the paramagnetic lanthanides indicate that the hydration number is 3, [Ln(bped)(H2O)(2)](+), and that an overall coordination number of 9 is maintained across the lanthanide series.},
	keywords = {AQUEOUS-SOLUTION, CARBOXYLATES, COMPLEXES, COORDINATION-NUMBER, EDTA, GADOLINIUM(III), NMR, NUCLEAR MAGNETIC-RESONANCE, polarization, SHIFT-REAGENTS, SHIFTS, WATER-MOLECULES},
	isbn = {0020-1669},
	url = {<Go to ISI>://A1997WQ49000007},
	author = {Caravan, P. and Mehrkhodavandi, Parisa and Orvig, Chris}
}
@article {3926,
	title = {Cationic lanthanide complexes of N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetic acid (H(2)bped)},
	journal = {Inorganic Chemistry},
	volume = {36},
	number = {7},
	year = {1997},
	note = {ISI Document Delivery No.: WQ490Times Cited: 22Cited Reference Count: 51},
	month = {Mar},
	pages = {1316-1321},
	type = {Article},
	abstract = {A series of monocationic lanthanide complexes containing the ligand N,N{\textquoteright}-bis(2-pyridylmethyl)ethylenediamine-N,N{\textquoteright}-diacetate(2-) (bped(2-)) have been prepared and isolated as either the hexafluorophosphate or perchlorate salts. The complexes have been characterized by H-1 and C-13 NMR, +LSIMS, IR, and elemental analysis. Complex formation constants have been measured in water at 25 degrees C (mu = 0.16 M (NaCl)). log K (Ln(bped)](+)) (log K([Ln(bped)(OH)])): Ln = La, 10.81 (0.06); Ln = Nd, 11.99 (1.45); Ln = Gd, 12.37 (2.10); Ln = Ho, 12.31 (3.00); Ln = Yb, 13.32 (4.43). The stability constants for [M(bped)](+) increase from La(III) to Nd(III), plateau to Ho(III), and increase again to Yb(III), while the formation constants for [Ln(bped)(OH)] increase almost linearly with atomic number. The solution structures of the [Ln(bped)](+) complexes have been probed by multinuclear NMR (H-1, C-13, O-17) studies, and these indicate only one isomer present in solution; this isomer has 2-fold symmetry and is rigid at 20 degrees C on the NMR time scale. O-17 NMR studies of the paramagnetic lanthanides indicate that the hydration number is 3, [Ln(bped)(H2O)(2)](+), and that an overall coordination number of 9 is maintained across the lanthanide series.},
	keywords = {AQUEOUS-SOLUTION, CARBOXYLATES, COMPLEXES, COORDINATION-NUMBER, EDTA, GADOLINIUM(III), NMR, NUCLEAR MAGNETIC-RESONANCE, polarization, SHIFT-REAGENTS, SHIFTS, WATER-MOLECULES},
	isbn = {0020-1669},
	url = {<Go to ISI>://A1997WQ49000007},
	author = {Caravan, P. and Mehrkhodavandi, Parisa and Orvig, Chris}
}
@article {3266,
	title = {POTENTIOMETRIC, CALORIMETRIC, AND SOLUTION NMR-STUDIES OF A TRIDENTATE LIGAND WHICH HAS A MARKED PREFERENCE FOR FORMATION OF BIS(LIGAND) VERSUS MONO(LIGAND) LANTHANIDE COMPLEXES AND WHICH EXHIBITS HIGH SELECTIVITY FOR HEAVIER LANTHANIDES},
	journal = {Journal of the American Chemical Society},
	volume = {117},
	number = {45},
	year = {1995},
	note = {ISI Document Delivery No.: TE739Times Cited: 69Cited Reference Count: 59},
	month = {Nov},
	pages = {11230-11238},
	type = {Article},
	abstract = {A new water-soluble N4O3 tripodal amine phenol ligand, tris(((2-hydroxy-5-sulfobenzyl)amino)ethyl)amine (H(3)TRNS) has been synthesized, and its complexation properties with six lanthanide(III) ions (Ln, Nd, Gd, Ho, Yb, Lu) have been probed. In water, the ligand coordinates in a tridentate fashion through the three phenolate oxygen atoms to give mono- and bis(ligand) complexes. The bis complexes are proposed to be 7-coordinate containing one bound water as evinced by O-17 NMR experiments on the Dy3+ complex. while the mono complexes are proposed to have a coordination number of eight or nine. The stepwise formation constants for the 1:1 and 2:1 (L:M) complexes have been measured at 25 degrees C (mu = 0.16 M NaCl) for Nd3+ (log K-1 = 6.41, log K-2 6.34), Gd3+ (log K-1 = 6.67, log K-2 = 7.69), Ho3+ (log K-1 = 7.67, log K-2 = 8.75), and Yb3+ (log K-1 = 8.53, log K-2 = 9.73). The formation constants show an increasing affinity and an unprecedented selectivity for the heavier lanthanides (beta(2(yb)) - beta(2(Nd)) = 10(5.5)). Furthermore, the stepwise stability constant for the 2:1 complex is increasingly greater than that for the 1:1 complexes of Gd3+, Ho3+, and Yb3+, while K-1 and K-2 for the 1:1 and 2:1 complexes of Nd3+ are approximately the same. Solution calorimetry shows that the selectivity for the heavier lanthanides is an enthalpic effect (Delta H-beta 2 = -45.11 (Yb) and -13.71 kJ . mol(-1) (Nd)), while the anomalous behavior in formation constants (K-2 > K-1) is predominantly entropic (Delta S-2 > Delta S-1) and is rationalized in terms of salvation of the complexes, Lanthanum(III) forms only the 1:1 complex (log K = 5.65) which precipitates from solution.},
	keywords = {AGENTS, AMINE PHENOL LIGANDS, AQUEOUS, BIOLOGICAL-SYSTEMS, CHEMISTRY, EXCHANGE, HEPTADENTATE LIGANDS, METAL-IONS, NUCLEAR MAGNETIC-RESONANCE, probes, SHIFT-REAGENTS, WATER},
	isbn = {0002-7863},
	url = {<Go to ISI>://A1995TE73900021},
	author = {Caravan, P. and Hedlund, T. and Liu, S. and Sjoberg, S. and Orvig, Chris}
}
