98943-66-9Relevant academic research and scientific papers
Functionalized Trigonal Lanthanide Complexes: A New Family of 4f Single-Ion Magnets
Buch, Christian D.,Hansen, Steen H.,Tram, Camilla M.,Mitcov, Dmitri,Piligkos, Stergios
, p. 16328 - 16340 (2020)
We report the synthesis, characterization, and magnetic properties of eight neutral functionalized trigonal lanthanide coordination complexes LnL with Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5), Tm (6), Yb (7), Lu (8). These were prepared through a one-pot synthesis where, first, the ligand H3L was synthesized in situ through a Schiff base reaction of tris(2-aminoethyl)amine with 2,6-diformyl-p-cresol. Following addition of Ln(OTf)3xH2O and base, LnL was obtained. Powder X-ray diffraction confirms that all complexes are isostructural. LnL contain pendant, noncoordinating carbonyl functions that are reactive and represent direct anchoring points to appropriately functionalized surfaces. Furthermore, these reactive carbonyl functions can be used to postfunctionalize LnL: For example, with aromatic πsystems. We present herein the Schiff base condensation of 7 with benzylamine to yield 9 as well as the characterization and magnetic properties of 9. Our study establishes LnL as a truly versatile module for the surface deposition of Ln-based single-ion magnets.
Neutral and ionic multiple hydrogen bonded moieties in crystal structure of a one tripodal Schiff base
Ko?odziej, Beata,Dominiak, Paulina M.,Ko?cielecka, Anna,Schilf, Wojciech,Grech, Eugeniusz,Wo?niak, Krzysztof
, p. 133 - 139 (2004)
Structural and spectroscopic properties of solid tris(3-formyl-5-methyl-2- salicylidenamino-ethyl)amine have been investigated. This is a compound containing two moieties with triple Schiff base fragments. One of the moieties has all three neutral intramolecular O-H?N hydrogen bonds, whereas there are only ionic H-bonds in the other moiety. Both moieties form cavities with the amine N atom lone electron pairs inside strongly shielded by three aliphatic wings. The H-bond formed in the Schiff fragments influence the other structural parameters of the nearest aromatic parts of the moieties. 13C and 15N CP/MAS NMR results (chemical shifts) allow to identify two pairs of Schiff and amino nitrogen nuclei thus supporting formation of the two types of moieties in the crystal lattice.
Synthesis of first acyclic trinuclear ruthenium(II) phenolate schiff base complex from acyclic tripodal and macrobicyclic ligands
Mangayarkarasi, Nagarathinam,Korupoju, Srinivas R.,Aneetha, Halikhedkar,Zacharias, Panthappally S.
, p. 442 - 450 (2007/10/03)
An acyclic trinuclear ruthenium(II) Schiff base complex Ru3H3L1(DMSO)6Cl6, 1, has been isolated for the first lime from preformed acyclic tripodal ligands H3L1, H3L2 and also from macrobicyclic ligand H3L3 instead of the dinuclear ruthenium complex 2. The ligand H3L1 crystallizes in space group R 3 and exhibits carry over of molecular trigonal symmetry into crystal. Trigonal network is due to intermolecular interactions of aminomethylene (N-CH2) proton and formyl (CH=O) oxygen. The CSD analysis reveals that N-C-H... O=CH interaction is unique. The complex Ru3H3L1(DMSO)6Cl6 1 crystallizes in triclinic P 1 space group. Each ruthenium atom is coordinated by phenolic and formyl oxygens of ligand, sulphur atoms of two DMSO moieties in equitorial plane and two chloride ions in axial positions providing distorted octahedral geometry. The Ru-Ru distances in complex 1 indicate that there is no interaction between the metal centers. Further reaction of complex 1 with tren and ruthenium metal does not yield macrobicyclic complex 2 showing the inertness of the coordinated formyl group towards Schiff base condensation. The electronic spectrum of the complex shows charge transfer bands while cyclic voltammetry in dichloromethane solvent gives a single reversible redox couple at E1/2 = 0.87 V (vs Ag-AgCl) corresponding to Ru(II) to Ru(III) oxidation.
