Versatility of Terpyridine‐Functionalised Aryl Tetrazoles: Photophysical Properties, Ratiometric Sensing of Zinc Cations and Sensitisation of Lanthanide Luminescence

Abstract

Four new tetrazole-containing species, in conjugation with terpyridine moieties through phenyl or pyridyl linkers, have been synthesised and characterised. In the series, the tetrazole functional groups are either in their acidic form or are alkylated at the N2 position with a methyl group. The photophysical properties of the species reveal moderate UV or efficient blue fluorescent emission, with photoluminescence quantum yields of around 30 % and 80 % for UV and blue emission, respectively. The spectral profiles can be reversibly modulated through protonation/deprotonation, with changes being consistent with an increase of the electron density on the tetrazole

Structural Adjustments of Zn(II)‐Terpyridine Analogues by Pendent of Coligand: Solvothermal Syntheses, Crystal Structure, and Photophysical Behavior

“…[1][2][3][4][5] Rigid terpyridine derivatives and analogues have becoming one of promising building blocks in the crystal engineering field because of the inherent luminophoric effect and tridentate binding sites towards both transition and lanthanide metal cations. [6][7][8][9] As expected, the resulting terpyridine-derived metal complexes with discrete mononuclear entity, dimeric rectangular molecular box, one-dimensional double-chain, and threedimensional frameworks have been generated, exhibiting highly selective fluorescent sensing for pyrophosphate, tunable white emissions, and photocatalytic water splitting performance resulting significantly from the ligand-centered charge transfer and/or interligand πÀ π Interactions. [10][11][12][13][14][15][16][17] However, the structural diversity of the crystalline terpyridine-based metal complexes or extended coordination polymers is still a great challenge, and more efforts should be devoted by either adopting more efficiently synthetic strategies or incorporating with the second ligand to achieve synergistic coordination.…”

“…Coordination polymers constructed from bulky conjugated organic ligands and diverse metal nodes have attracted intriguing interests in gas‐absorption and separation, fluorescence sensing, electricity transmission, and photocatalysis due to their tailorable structures, higher framework robustness, and inter‐component electron/energy transfer [1–5] . Rigid terpyridine derivatives and analogues have becoming one of promising building blocks in the crystal engineering field because of the inherent luminophoric effect and tridentate binding sites towards both transition and lanthanide metal cations [6–9] . As expected, the resulting terpyridine‐derived metal complexes with discrete mononuclear entity, dimeric rectangular molecular box, one‐dimensional double‐chain, and three‐dimensional frameworks have been generated, exhibiting highly selective fluorescent sensing for pyrophosphate, tunable white emissions, and photocatalytic water splitting performance resulting significantly from the ligand‐centered charge transfer and/or interligand π−π Interactions [10–17] .…”

“…As compared with HL 1 ligand, the high‐energy absorbance of the two complexes is ascribed to the chromophoic L 1 − ‐based π‐π * transition with possible admixtures of n−π* transitions in the lower energy region of the broad band. The shoulder absorption of 2 is probably ascribed to the metal‐to‐ligand charge transfer [7] …”

“…The shoulder absorption of 2 is probably ascribed to the metal-to-ligand charge transfer. [7] Upon photoexcitation at 376 nm, both 1 and 2 display one broad emission centered at 458 nm (Figure 5b). Under the similar conditions, the free HL 1 ligand shows two efficient fluorescent emissions located at 422 and 522 nm.…”

Push-Pull Effect of Terpyridine Substituted by Triphenylamine Motive—Impact of Viscosity, Polarity and Protonation on Molecular Optical Properties

“…Most importantly, the introduction of strong electron donating groups into the electron acceptor terpy core gives rise to Intraligand Charge Transfer (ICT) transitions, which offer a large degree of control over the system’s optical properties [ 27 , 28 ]. Other remarkable aspects of these compounds are their optical sensitivity to the pH, polarity and viscosity of the local environment [ 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ].…”