Anion-Induced Structural Diversity of Zn and Cd Coordination Polymers Based on Bis-9,10-(pyridine-4-yl)-anthracene, Their Luminescent Properties, and Highly Efficient Sensing of Nitro Derivatives and Herbicides

Abstract

Luminescent coordination polymers (CPs) of Zn 2+ or Cd 2+ and bis-9,10-(pyridine-4-yl)-anthracene (BA) show different 1D and 2D topologies depending on the anion used in the precursor. Compounds {[Zn(μ 2-BA)(MeOH) 2 (p-Tos) 2 ]} n (1) and {[Zn(μ 2-BA)(MeOH) 2 (CF 3 CO 2) 2 ]} n (2) f o r m l i n e a r s t r u c t u r es a n d { B A @ [ Z n (μ 2-B A)-(MeOH) 2 (H 2 O) 2 ](CF 3 SO 3) 2 } n (3) featuring intercalation of uncoordinated BA molecules into linear ribbons. Cd-based CPs {[Cd(μ 2-BA) 2 (ClO 4) 2 ]•n(DCM)} n (4) and {[Cd(μ 2-BA)(MeOH) 2 (Dioxane)(η 2-SiF 6)]•mDioxane} n (5) form porous structures with 2D lattices. All complexes exhibit strong blue emission in the solid state with average lifetimes between 8 and 13 ns. The emission of compound 4 is sensitive to the presence of nitro aromatics, simazine, and trichloroanisole (TCA) and demonstrates nonlinear Stern−Volmer quenching kinetics. Limits of detection (LOD) of 15 and 16 ppb for picric acid and TCA were achieved, respectively.

Dual‐Emissive Platinum(II) Metallacage with a Sensitive Oxygen Response for Imaging of Hypoxia and Imaging‐Guided Chemotherapy

“…As shown in the UV/Vis spectra, the overlap (Figure 2a)b etween absorptions of the ligands allowed exciting both dyes simultaneously.M oreover,a fter the formation of the metallacage,t he bathochromic shift of the Soret band and the hypsochromic of the Qb and were both found for 3 ( Figure S7), indicating the prevented p-p stacking. [11,13] In the design principle,F RET was avoided, and this was verified by the negligible overlap between the fluorescent emission of 2 (maximum at 460 nm) [12] and the UV absorbance of 3 (maximum at 396 nm). Thedual-emission property of 1 in adeaerated atmosphere was evaluated in fluorescence experiments.Anacetone solution of the metallacage showed strong blue (420-480 nm) and very weak red (630-740 nm) emissions with 390 nm excitation.…”

Dual‐Emissive Platinum(II) Metallacage with a Sensitive Oxygen Response for Imaging of Hypoxia and Imaging‐Guided Chemotherapy

“…Moreover, after the formation of the metallacage, the bathochromic shift of the Soret band and the hypsochromic of the Q band were both found for 3 (Figure S7), indicating the prevented π‐π stacking [11, 13] . In the design principle, FRET was avoided, and this was verified by the negligible overlap between the fluorescent emission of 2 (maximum at 460 nm) [12] and the UV absorbance of 3 (maximum at 396 nm). The dual‐emission property of 1 in a deaerated atmosphere was evaluated in fluorescence experiments.…”

“…[10] However,t his complex suffers from p-p stacking that weakens its emission, [11] and thus itsu seful to use the metallacage to disperse it by taking advantage of the directional coordination self-assembly.T oa chieve ad ualemissive property,the emission of the other ligand cannot be in the red region, and Fçrster resonance energy transfer (FRET) should also be avoided to sustain as teady fluorescence.T herefore,a nthracene was selected as ab lue fluorophore. [12] Thec ombination of two ligands endows 1 with sensitive O 2 -responsive red phosphorescence and steady blue fluorescence.T he metallacage was also applied in hypoxia imaging in vitro and in vivo. Compared with traditional mono-emissive hypoxia probes,t he metallacage not only shows reversible and sensitive O 2 -reponsive phosphorescence but also provides am ore reliable standard for hypoxia imaging and detection by calculating the ratio between red and blue emissions.F or biomedical applications,a na mphiphilic diblock copolymer is employed to encapsulate the metallacage to prepare ananoparticulate formulation aiming to enhance the stability of the metallacage.B enefiting from the nanotechnology,t he circulation time and tumor accumulation of the metallacage-loaded nanoparticles are significantly improved, which facilitate the optimization of the imaging and therapeutic performances.…”

“…To achieve a dual‐emissive property, the emission of the other ligand cannot be in the red region, and Förster resonance energy transfer (FRET) should also be avoided to sustain a steady fluorescence. Therefore, anthracene was selected as a blue fluorophore [12] . The combination of two ligands endows 1 with sensitive O 2 ‐responsive red phosphorescence and steady blue fluorescence.…”

A fluorescent Cu(ii) complex as a dual functional sensor for selective and sensitive detection of acetone and Cd(ii) pollutants

“…In recent years, different coordination-based uorescent sensors have been established. [19][20][21][22] They have been employed to probe small organic molecules and metal ions via uorescence enhancing or quenching. Nevertheless, the rational design and synthesis of luminescent coordination complexes with exhibiting the desired structure and properties remain challenging.…”