Nickel(II), Cadmium(II), and Copper(II) Complexes Based on Ditopic Terpyridine Derivative Ligand: Syntheses, Crystal Structures, and Luminescent Properties

Abstract

Three complexes with the ditopic ligand 4Ј-[4-(quinolin-8yloxymethyl)phenyl]-2,2Ј:6Ј,2ЈЈ-terpyridine (abbreviated as L), [Ni(L) 2 ](CH 3 COO) 2 (1), [Cd(L) 2 ](ClO 4 ) 2 (2), and [Cu 2 (L) 2 ](ClO 4 ) 4 · 4DMF (3), were synthesized and characterized by elemental analysis, IR spectroscopy, and structurally analyzed by X-ray single-crystal diffraction. Interestingly, in complexes 1 and 2, two ligands adopt a tridentate chelating pattern where the oxaquinoline group is non-coordinated and coordinate with one M II ion (M = Ni for 1, M = Cd for 2) to form a mononuclear unit. In complex 3, two ligands bridge two Cu II 817 ions by pyridyl N atoms, ethereal O atoms, and quinolyl N atoms in a head-to-tail mode to generate a dinuclear [Cu 2 L 2 ] unit. Moreover, extended 1D and 2D supramolecular architectures are further constructed in 1-3 by multiple secondary interactions such as aromatic stacking and hydrogen bonding. Notably, the structural diversity of complexes 1-3 can be properly assigned to the central metal ions that have distinct coordination preferences. In addition, luminescent properties of the ligand and complex 2 were also investigated.

Crystal exploring, Hirshfeld surface analysis, and properties of 4′‐(furan‐2‐yl)‐2,2′:6′,2″‐terpyridine complexes of nickel (II): New precursors for the synthesis of nanoparticles

“…The red shift of all complexes could be attributed to the coordination of ftpy to the Ni (II) center. [ 69,70 ]…”

Entropically Favoured Assembly of Pyrazine‐Based Helical Fibers into Superstructures: Achiral/ Chiral Guest‐Induced Chirality Transformation

“…We believe that due to its moderate nature and preference for higher coordination numbers,N i 2+ ions interact strongly with the helical fibers,i nc ontrast to other metal ions,a nd can hence influence the packing arrangement. [24] To understand the interactions between 1 and Ni 2+ ions, we carried out FTIR and 1 HNMR studies.I nt he FTIR studies,t he stretching mode of the carbonyl groups and stretching and bending modes of amide groups (NH) are visible in solution (Figure S18 a). In the presence of Ni 2+ ions, the stretching bands corresponding to the carbonyl and amide groups are shifted ( Figure S18 band Table S2), which suggests that the nickel ions are coordinating to the assemblies through the carbonyl and amide groups.T he 1 HNMR spectra of 1 were measured in the presence of varying concentrations of Ni 2+ ions (2-8 equiv) in [D 6 ]DMSO/D 2 O( 9:1).…”

“…However, in the absorption studies, the presence of Al 3+ (300 equiv) and Cu 2+ ions (300 equiv) lead to no changes in the absorption of 1 and the corresponding CD spectra of the solution was found to be silent in both cases (Figure S17). We believe that due to its moderate nature and preference for higher coordination numbers, Ni 2+ ions interact strongly with the helical fibers, in contrast to other metal ions, and can hence influence the packing arrangement …”

Synthesis, Crystal Structure, Luminescence and Magnetism of Three Novel Coordination Polymers Based on Flexible Multicarboxylate Zwitterionic Ligand

“…As for complexes 2 and 3, no clear photoluminescence was observed. The luminescence emissions are probably quenched by the Mn(II) and Cu(II) ions, when excited at 350 nm for 2 and 348 nm for 3 respectively, which may be a result of the d-d transitions of unfilled d-orbitals of Mn(II) and Cu(II) ions [24,25]. …”