One- and two-dimensional polymerisation of homoleptic M(II)-complexes of 4′-(3-pyridyl)-2,2′;6′,2″-terpyridine in the solid state: A combined study by XRD, cyclic voltammetry, NMR and UV–Vis spectroscopies

A Bichromophoric Approach to Induce Luminescence - A Blend of Experimental and Theoretical Studies

Two homoleptic terpyridyl complexes of Ru(II), 1 and Fe(II), 2 were synthesized using a ligand L1 that contained a phenyl spacer between an anthracenyl (An) and a terpyridyl (tpy) moiety. An equilibrated-bichromophoric strategy was adopted to induce photoluminescence in 1 and 2. A glimpse into the excited state photophysical properties of 1 and 2 revealed that 1 exhibited NIR emission at ~700 nm with an excited state lifetime components of 1.33 and 6.52 ns. On the other hand, 2 was found to be non-luminescent. The origin of emission in case of 1 was attributed to the effect of phenyl spacer which rendered the 3An state to be nearly isoenergetic to the emissive 3MLCT state of 1 facilitating 3MLCT-3An equilibrium. This fact was supported by experimental (photocurrent generation) and theoretical (potential energy diagram) evidences.

Extreme enhancement of secondary chirality through coordination-driven steric changes of terpyridyl ligand in glutamide-based molecular gels

Aggregation-induced chirality is potentially useful in sensor technology applications. Herein we show extreme enhancement of secondary chirality through coordination-driven steric changes of terpyridyl ligand in molecular gels. The secondary chirality reflecting on enhancement of chiral signals (i.e., circular dichroism (CD) and circularly polarised luminescence (CPL)) of the molecular gels formed from glutamide-attached terpyridine (G-tpy) is extremely enhanced by the coordination of its terpyridyl groups to metal ions such as Cu2+, Zn2+ and Ru2+, which is due to dramatic changes in the stacked structure of the chromophore groups through the formation of metal ion complex. Metal-free terpyridine exists in a non-planar geometry, which suppress π-π stacking interactions among aggregates. The planarity of the terpyridyl group is improved through metal-ion complexation, which induces the metal-ion-coordinated terpyridyl groups to stack. The thermal stabilities of the CD signals are strongly affected by the metal-ion species. CPL signal is generated in the molecular gel formed from G-tpy-Zn2+ complex accompanied by chelation-enhanced fluorescence. It is expected that large and sensitive coordination-driven secondary chirality signals (CD and CPL) are useful for sensing guest molecules and the surrounding environment.

Terpyridine-based metallosupramolecular constructs: tailored monomers to precise 2D-motifs and 3D-metallocages

Comprehensive summary of the recent developments in the growing field of terpyridine-based, discrete metallosupramolecular architectures.

Synthesis of discrete Re(i) di- and tricarbonyl assemblies using a [4 × 1] directional bonding strategy

Discrete assembly of two Re(i) squares was achieved by a simple [4 × 1] strategy where the complexes, [Re(4-pytpy-κ²N)(CO)₃Br] and [Re(4-pytpy-κ³N)(CO)₂Br], act as their own ligands. The properties of the assemblies and their precursors are described along with solid-state X-ray diffraction studies.

Crystal structure of bis-(2,2':6',2''-terpyridine-κ(3) N,N',N'')nickel(II) dicyanidoaurate(I)

In an ionic compound composed of bis­(2,2′:6′,2′′-terpyridine)­nickel(II) dications and dicyanidoaurate(I) dianions in a 1:2 ratio, the two tridentate terpyridine ligands define the coordination of the Ni²⁺ cation, resulting in a nearly octa­hedral coordination sphere, although there is not any imposed crystallographic symmetry about the Ni²⁺ site.

The title compound, [Ni(C₁₅H₁₁N₃)₂][Au(CN)₂]₂, is an ionic compound composed of bis­(2,2′:6′,2′′-terpyridine)­nickel(II) dications and dicyanidoaurate(I) anions in a 1:2 ratio. The two tridentate terpyridine ligands define the coordination of the Ni²⁺ cation, resulting in a nearly octa­hedral coordination sphere, although there is not any imposed crystallographic symmetry about the Ni²⁺ site. The two nearly linear dicyanidoaurate(I) anions [C—Au—C = 179.0 (2) and 178.2 (2)°] contain a short aurophilic inter­action of 3.1017 (3) Å. The structure does not demonstrate any π–π stacking. Non-classical C—H⋯N inter­actions between the cations and anions build up a three-dimensional network.