24220-43-7Relevant articles and documents
A New Class of Lanthanide Complexes with Three Ligand Centered Radicals: NMR Evaluation of Ligand Field Energy Splitting and Magnetic Coupling
Hiller, Markus,Sittel, Thomas,Wadepohl, Hubert,Enders, Markus
, p. 10668 - 10677 (2019)
Combination of three radical anionic Ph-BIAN ligands (Ph-BIAN=bis-(phenylimino)-acenaphthenequinone) with lanthanoid ions leads to a series of homoleptic, six-coordinate complexes of the type Ln(Ph-BIAN)3. Magnetic coupling data were measured by paramagnetic solution NMR spectroscopy. Combining 1H NMR with 2H NMR of partially deuterated compounds allowed a detailed study of the magnetic susceptibility anisotropies over a large temperature range. The observed chemical shifts were separated into ligand- and metal-centered contributions by comparison with the Y analogue (diamagnetic at the metal). The metal-centered contributions of the complexes with the paramagnetic ions could then be separated into pseudocontact and Fermi contact shifts. The latter is large within the Ph-BIAN scaffold, which shows that magnetic coupling is significant between the lanthanide ion and the radical ligand. Pseudocontact shifts were further correlated to structural data obtained from X-ray diffraction experiments. Ligand-field parameters were determined by fitting the temperature dependence of the observed magnetic susceptibility anisotropies. The electronic structure determined by this approach shows, that the Er and Tm analogues are candidates for single molecule magnets (SMM). These results demonstrate the possibilities for the application of NMR spectroscopy in investigations of paramagnetic systems in general and single molecule magnets in particular.
Synthesis, characterization of zinc complexes with neutral α-diimine ligands and application in ring-opening polymerization of σ-caprolactone
Wang, Xiaodan,Liu, Xuehong,Huang, Ju
, p. 773 - 776 (2017/12/08)
A series of neutral α-diimine ligands with diacetyl and acenaphthenequinone skeletons were prepared by the reaction between diacetyl and the corresponding aromatic amine. These ligands reacted with ZnCl2 to generate symmetric α-diimine zinc complexes C1-C
Cationic platinum(II) complexes bearing aryl-BIAN ligands: Synthesis and structural and optoelectronic characterization
Obrien, Cameron,Wong, Michael Yin,Cordes, David B.,Slawin, Alexandra M. Z.,Zysman-Colman, Eli
, p. 13 - 22 (2015/01/30)
Five cationic platinum(II) complexes bearing a 2-(3′-substituted aryl)pyridine cyclometalating ligand (C^N) and a neutral Ar-BIAN ligand have been synthesized: [Pt(ppy)(PhBIAN)]PF6 (1), [Pt(3Fppy)(PhBIAN)]PF6 (2), [Pt(3MeOppy)(PhBIAN)]PF6 (3), [Pt(3MeOppy)(4-FPhBIAN)]PF6 (4), [Pt(ppy)(4-MeOPhBIAN)]PF6 (5). All complexes have been characterized by NMR spectroscopy and mass spectrometry. Complexes 2 and 3 have been characterized by X-ray crystallography. Structure-property relationships were established from UV-visible spectroscopy and cyclic voltammetry studies. Interestingly, we found that when both the C^N and the Aryl-BIAN ligands contained electron-donating MeO groups the absorption spectrum for the platinum complex extended out to 650 nm. The electrochemical studies of these complexes established that they are electronically compatible dye molecules for dye-sensitized solar cells.
