Metal-Directed Synthesis of Enantiomerially Pure Dimetallic Lanthanide Luminescent Triple-Stranded Helicates

Abstract

The synthesis and photophysical evaluation of two enatiomerially pure dimetallic lanthanide luminescent triple-stranded helicates is described. The two systems, formed from the chiral (R,R) ligand 1 and (S,S) ligand 2, were produced as single species in solution, where the excitation of either the naphthalene antennae or the pyridiyl units gave rise to Eu(III) emission in a variety of solvents. Excitation of the antennae also gave rise to circularly polarized Eu(III) luminescence emissions for Eu(2):1(3) and Eu(2):2(3) that were of equal intensity and opposite sign, confirming their enantiomeric nature in solution providing a basis upon which we were able to assign the absolute configurations of Eu(2):1(3) and Eu(2):2(3).

The btp [2,6-bis(1,2,3-triazol-4-yl)pyridine] binding motif: a new versatile terdentate ligand for supramolecular and coordination chemistry

“…[16][17][18][19]53,58,[138][139][140][141] Hence they lend themselves to use in other applications such as in biological sensing, OLEDs, and as imaging agents, etc. 142,143 Flood and co-workers proved that btp-ligand 3a could form a stable coordination complex with Eu(III), which is to the best of our knowledge, the first example of such a system in the literature.…”

The effect on the lanthanide luminescence of structurally simple Eu(iii) cyclen complexes upon deprotonation of metal bound water molecules and amide based pendant arms

“…15 Herein, examples 2-4 were developed by incorporating the naphthalene antenna through a pendant amide linkage, either via a methylene spacer or as part of the amide functionality. All the complexes were designed so that they would give rise to an eight coordinate environment around the lanthanide ion, which should ensure that each metal would possess a single metal bound water molecule, giving an overall nine coordinate complex.…”

Diastereoselective Self‐Assembly of a Homochiral Europium Triangle from a BipyoxazolineCarboxylate Ligand

“…[1,[4][5][6][7][8][9][10] Fewer examples of chiral polynuclear assemblies have been described for lanthanides. [3,[11][12][13][14][15][16] Some original examples of chiral assemblies were obtained from the controlled hydrolysis [11][12][13] or CO 2 fixation reactions [15,16] of lanthanide salts in the presence of chiral ligands. In these synthetic methods the hydroxo and the carbonate groups play an important role in the formation of the heteroleptic assemblies causing the rational design of the final assembly to be difficult.…”