title: Interaction of 6,6''-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2':6',2''-terpyridine (CyMe4-BTTP) with some trivalent ions such as lanthanide(III) ions and americium(III).
abstract: The new ligand 6,6''-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2':6',2''-terpyridine (CyMe4-BTTP) has been synthesized in 4 steps from 2,2':6',2''-terpyridine. Detailed NMR and mass spectrometry studies indicate that the ligand forms 1:2 complexes with lanthanide(III) perchlorates where the aliphatic rings are conformationally constrained whereas 1:1 complexes are formed with lanthanide(III) nitrates where the rings are conformationally mobile. An optimized structure of the 1:2 solution complex with Yb(III) was obtained from the relative magnitude of the induced paramagnetic shifts. X-Ray crystallographic structures of the ligand and of its 1:1 complex with Y(III) were also obtained. The NMR and mass spectra of [Pd(CyMe4-BTTP)]n(2n+) are consistent with a dinuclear double helical structure (n = 2). In the absence of a phase-modifier, CyMe4-BTTP in n-octanol showed a maximum distribution coefficient of Am(III) of 0.039 (±20%) and a maximum separation factor of Am(III) over Eu(III) of 12.0 from nitric acid. The metal(III) cations are extracted as the 1:1 complex from nitric acid. The generally low distribution coefficients observed compared with the BTBPs arise because the 1:1 complex of CyMe4-BTTP is considerably less hydrophobic than the 1:2 complexes formed by the BTBPs. In M(BTTP)(3+) complexes, there is a competition between the nitrate ions and the ligand for the complexation of the metal.
authors.affiliation: Department of Chemistry, The University of Reading, Whiteknights, Reading, UKRG6 6AD. f.lewis@reading.ac.uk, l.m.harwood@reading.ac.uk.
authors.forename: Frank W
authors.initials: FW
authors.lastname: Lewis
authors.forename: Laurence M
authors.initials: LM
authors.lastname: Harwood
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Hudson
authors.forename: Michael G B
authors.initials: MG
authors.lastname: Drew
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Modolo
authors.forename: Michal
authors.initials: M
authors.lastname: Sypula
authors.forename: Jean F
authors.initials: JF
authors.lastname: Desreux
authors.forename: Nouri
authors.initials: N
authors.lastname: Bouslimani
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Vidick