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Coordinative supramolecular cages with adjustable cavities have found extensive applications in various fields, but the cavity modification strategies for multi‐functional structures are still challenging. Here, we present a tension‐driven self‐expansion strategy for construction of multi‐cavity cages with high structural complexity. Under the regulation of strain‐induced capping ligands, unprecedented heteromorphosis triple‐cavity cages S2/S4 were obtained based on a metallo‐organic ligand (MOL) scaffold. The heteromorphosis cages exhibited significant higher cavity diversity than the homomorphous double‐cavity cages S1/S3; all of the cages were thoroughly characterized through various analytical techniques including (1D and 2D) NMR, ESI‐MS, TWIM‐MS, AFM, and SAXS analyses. Furthermore, the encapsulation of porphyrin in the cavities of these multi‐cavity cages were investigated. This research opens up new possibilities for the architecture of heteromorphosis supramolecular cages via precisely controlled "scaffold‐capping" assembly with preorganized ligands, which could have potential applications in the development of multifunctional structures with higher complexity. [ABSTRACT FROM AUTHOR]

Inverted perovskite solar cells (PSCs) mainly adopt polytriarylamine (PTAA) for the hole transport material (HTM), which usually brings about inferior interfacial contact owing to their hydrophobicity, high‐lying highest occupied molecular orbital energy level, and deficiency of passivation groups. Herein, a series of donor–π–acceptor (D–π–A) type small molecules is demonstrated based on 2,2′:6′,2″‐terpyridine (TPy) as the acceptor moiety, benzene ring as the π‐linker, and incorporating various donors to act as HTMs. These TPy‐based molecules coated atop PTAA manipulate the energy level and surface wettability, but the incorporation of the phenoxazine (POZ) donor can be prominent for enhancing charge transport and defect passivation, thereby simultaneously addressing the above‐mentioned issues. The highest power conversion efficiency of 22.36% can be achieved with an open‐circuit voltage (VOC) of 1.15 V, a short‐circuit current density (JSC) of 23.96 mA cm−2, and a fill factor (FF) of 81.16% for the optimized POZ‐TPy‐modified device. Moreover, the power PCE of a large POZ‐TPy‐modified device (1.96 cm2) can still reach more than 21%. These results are among one of the highest efficiencies for inverted PSCs, indicating the enormous potential of POZ‐TPy HTM in future perovskite applications. [ABSTRACT FROM AUTHOR]

Three new complexes containing 2‐thiophenylterpyridine (TP) ligand, namely, [Co(stpy)2]Cl2 (Co‐TP), [Ni(stpy)Cl2]2 (Ni‐TP) and [Pd(stpy)Cl]Cl (Pd‐TP) were synthesized and subsequently characterized employing various spectroscopic techniques including UV–Visible, IR, 1H NMR, EPR, and ESI‐MS analysis. ESI‐MS spectra suggested the complexes Co‐TP and Ni‐TP to be six coordinated with two ligand units and the complex Pd‐TP to be a four‐coordinated mononuclear square planar complex. The dimeric nature of the complex Ni‐TP (M2L2Cl4) was established by X‐ray diffraction analysis, which confirmed the bridging of two nickel centers by two chloride ions. The ligand and complexes were assessed for their cytotoxic behavior by using MTT colorimetric assay. The compounds TP, Co‐TP, Ni‐TP and Pd‐TP displayed significant antiproliferative activity on A549 (human lung carcinoma) and MM2 (human breast cancer) cell lines and had no toxic effect on human normal embryonic kidney cells (HEK 293). Further, the morphological changes associated with MM2 and A549 cells triggered by the tested compounds due to apoptosis have been validated with the help of AO‐EB and DAPI staining assays. [ABSTRACT FROM AUTHOR]

Inverted perovskite solar cells (PSCs) mainly adopt polytriarylamine (PTAA) for the hole transport material (HTM), which usually brings about inferior interfacial contact owing to their hydrophobicity, high‐lying highest occupied molecular orbital energy level, and deficiency of passivation groups. Herein, a series of donor–π–acceptor (D–π–A) type small molecules is demonstrated based on 2,2′:6′,2″‐terpyridine (TPy) as the acceptor moiety, benzene ring as the π‐linker, and incorporating various donors to act as HTMs. These TPy‐based molecules coated atop PTAA manipulate the energy level and surface wettability, but the incorporation of the phenoxazine (POZ) donor can be prominent for enhancing charge transport and defect passivation, thereby simultaneously addressing the above‐mentioned issues. The highest power conversion efficiency of 22.36% can be achieved with an open‐circuit voltage (VOC) of 1.15 V, a short‐circuit current density (JSC) of 23.96 mA cm−2, and a fill factor (FF) of 81.16% for the optimized POZ‐TPy‐modified device. Moreover, the power PCE of a large POZ‐TPy‐modified device (1.96 cm2) can still reach more than 21%. These results are among one of the highest efficiencies for inverted PSCs, indicating the enormous potential of POZ‐TPy HTM in future perovskite applications.

• 4′-phenylterpyridine, synthesis, and theoretical studies toward metal-sensor properties. • 4′-phenylterpyridine derivatives are multifunctional chemosensor of Zn2+, Cd2+, Hg2+ ions. • Host-guest interaction selectivity study of Zn2+, Cd2+, Hg2+ ions. • Research of optical features, including ground and excited estates from the TD-DFT methodologies. • Structural characteristics and EDA-NOCV calculations to unraveling the metal–ligand interactions and the sensor capabilities for organic and metal–ligand complexes. 4′-phenylterpyridine (TPY) involves four conjugated rings, leading to a multi-resonant chromophore with exceptional luminescent features. Further functionalization of the 4′-phenyl moiety enables a versatile set of chemosensors. In the series, the optical transitions remain similar, where λ max ranges from 253 to 269 nm, with emissions from 357 to 365 nm. Calculations of the natural transition orbitals NTOs deliver the localized hole-electron densities, indicating that the electronic transitions vary as a local-excitation (LE), charge transfer (CT), and mixed LE-CT along with the set. We employ the energy decomposition analysis to evaluate the possible coordination toward Zn(II), Cd(II), and Hg(II) cations, showing a favorable formation of complexes, where the interaction nature exhibits a ∼ 49 and ∼ 50 % electrostatic and orbital character for the Zn(II), Cd(II) and Hg(II) centers. Furthermore, the density deformation channels confer an explicit picture of the bonding scheme, denoting π - and σ-bonding contributions. [ABSTRACT FROM AUTHOR]

Analysis of the weak interactions within the crystal structures of 33 complexes of various 4′-aromatic derivatives of 2,2′:6′,2″-terpyridine (tpy) shows that interactions that exceed dispersion are dominated, as expected, by cation⋯anion contacts but are associated with both ligand–ligand and ligand–solvent contacts, sometimes multicentred, in generally complicated arrays, probably largely determined by dispersion interactions between stacked aromatic units. With V(V) as the coordinating cation, there is evidence that the polarisation of the ligand results in an interaction exceeding dispersion at a carbon bound to nitrogen with oxygen or fluorine, an interaction unseen in the structures of M(II) (M = Fe, Co, Ni, Cu, Zn, Ru and Cd) complexes, except when 1,2,3-trimethoxyphenyl substituents are present in the 4′-tpy.

Based on the predesigned self‐selective complexation, metallo‐supramolecular P3HT‐b‐PEO diblock copolymers with varying block ratios were synthesized, and their oriented polymer films generated during solvent evaporation in a 9 T magnetic field were investigated. An anisotropic, ordered layer structure was achieved using [P3HT20‐Zn‐PEO107] and carefully characterized by polarized optical microscopy (POM), AFM, polarized UV/Vis spectroscopy, and GI‐SAXS/WAXS. The PEO‐removed [P3HT20‐Zn‐PEO107] film was obtained after decomplexation with TEA‐EDTA under mild conditions, and the selective removal of PEO domains was evidenced by UV/Vis and ATR‐FTIR spectroscopy. Anisotropic photoconductivity of the magnetically aligned film was evaluated by flash‐photolysis time‐resolved microwave conductivity (FP‐TRMC) measurements. The results indicated that the presence of insulating crystalline PEO segments diminished the photoconductivity along the P3HT backbone direction. [ABSTRACT FROM AUTHOR]

New di- and tetrasubstituted thiacalix[4]arenes in cone and 1,3-alternate configurations containing terpyridine and triazole fragments at the lower rim of the macrocycle, as well as model triazole-terpyridine, are synthesized. The structures and purity of the compounds are confirmed by NMR spectroscopy and high-resolution MALDI mass spectrometry. The compounds form luminescent complexes with lanthanide cations (europium and terbium) in a chloroform-methanol (10: 1) system during fluorimetric titration. The possibility of antenna ef ect during fluorescence sensitization in lanthanides by the thiacalixarene ligands is demonstrated. Successful immobilization of the terpyridine receptors on a solid substrate makes it possible to consider the Langmuir-Blodgett films on the basis of these receptors as promising adsorbents of lanthanide from nonaqueous media or organic salts and also provides new opportunities for the investigation of the luminescence characteristics of lanthanide complexes in thin films. [ABSTRACT FROM AUTHOR]

A series of molecules in which 9H‐carbazole (electron donor, D) and 2,2′:6′,2′′‐terpyridine (electron acceptor, A) are connected through rigid π‐conjugated bridges (D‐π‐A systems) have been synthesized and their photophysical properties examined in detail, with the support of DFT calculations. The bridges are made of different sequences of ethynylene, phenylene, and anthracene groups. The synthetic strategies involve condensation of 2‐acetylpyridine with the aromatic aldehyde moiety on different functionalized π‐conjugated bridges and couplings with carbazole derivatives. The system incorporating anthracene in the bridge shows the typical absorption and emission fingerprints of this polycyclic hydrocarbon. The other systems have HOMOs and LUMOs centred, respectively, over the carbazole and the bridge and exhibit solvatochromic charge‐transfer (CT) luminescence with high photoluminescence yield up to 70 %, except when an ethynylene unit is directly attached to the carbazole ring, due to a trans‐bent non‐emissive π–σ* excited state. [ABSTRACT FROM AUTHOR]

Aim: This study was designed to synthesize a novel series of terpyridines with potential antibacterial properties, targeting multidrug resistance. Materials & methods: Terpyridines ( 4a-h and 6a-c ) were synthesized via a one-pot multicomponent reaction using 2,6-diacetylpyridines, benzaldehyde derivatives and malononitrile or ethyl 2-cyanoacetate. The reactions, conducted under grinding conditions with glacial acetic acid, produced high-yield compounds, confirmed by spectroscopic data. Results: The synthesized terpyridines exhibited potent antibacterial activity. Notably, compounds 4d and 4h demonstrated significant inhibition zones against Staphylococcus aureus and Bacillus subtilis , outperforming ciprofloxacin. Conclusion: Molecular docking studies highlighted compounds 4d , 4h  and 6c as having strong binding affinity to DNA gyrase B, correlating with their robust antibacterial activity, suggesting their potential as effective agents against multidrug-resistant bacterial strains.

A series of cationic [Ru(L)(PPh3)2Cl]+ (1–3) and neutral [Ru(L)(PPh3)Cl2] (4–6) RuII complexes were synthesized by reacting [RuCl2(PPh3)2] with 4′‐(aryl)‐2,2′:6′,2′′‐terpyridyl‐based ligands (L1–L3) with various aryl groups (tolyl, phenyl and 4‐fluorophenyl). The synthesized RuII complexes were unambiguously characterized by various spectroscopic techniques such as FTIR and multinuclear NMR spectroscopy as well as HRMS. The neutral complexes (4–6) were also structurally characterized by single‐crystal X‐ray diffraction studies. Photophysical and electrochemical studies of the RuII complexes were performed to elucidate the effects of the 4′‐aryl substituents of L1–L3. These RuII complexes show good catalytic activities in the transfer hydrogenation (TH) of ketones with a wide substrates scope in 2‐propanol under reflux. An optimization study revealed that the neutral RuII complexes are better catalysts than the cationic RuII complexes for TH reactions. Finally, [Ru(L1)(PPh3)2H]+ (7) with a [RuII–H] functionality was successfully synthesized and isolated and is proposed as the catalytically active species. A control experiment with the [RuII–H] complex in the absence of base was performed to establish the mechanism for the catalytic TH of ketones. [ABSTRACT FROM AUTHOR]

The preparation of 24-functionalized 12,22:26,32-terpyridines (4′-functionalized 3,2:6′,3″-terpyridines) by the reaction of three 4-alkoxybenzaldehydes with 3-acetylpyridine and ammonia was investigated; under identical reaction conditions, two (R =nC4H9, C2H5) gave the expected products whereas a third (R = nC3H7) gave only a cyclohexanol derivative derived from the condensation of three molecules of 3-acetylpyridine with two of 4-(n-propoxy)benzaldehyde. A comprehensive survey of “unexpected” products from reactions of ArCOCH3 derivatives with aromatic aldehydes is presented. Three different types of alternative product are identified.

Novel derivatives of 4'-phenyl-2,2':6′,2″-terpyridine (tpy) with ethynyl ( T1 ), 2-ethynyl-9,9-dioctylfluorene ( T2 ), 9,9-dioctylfluorene ( T3 ), 9-ethynyl-10-decyloxyanthracene ( T4 ) substituents were obtained via Sonogashira or Suzuki-Miyaura coupling reactions, respectively, and thoroughly characterized. The presence of ethynyl bridge impacts photophysical properties of novel compounds by shifting absorption and emission spectra towards longer wavelengths as compared to T3 , where fluorene is connected with tpy via a single bond. TGA measurements showed that among the new terpyridines those obtained as solids exhibited high thermal stability as opposed to those which were oils (tpy containing fluorene motif). Due to the fact that high thermal stability of 4'-phenyl-2,2':6′,2″-terpyridine derivatives showed photoluminescence (PL) quantum yield (Φ) in the range of 27–84% in solution, their electroluminescence ability was tested in diodes with guest-host configuration. For the compounds dispersed in a matrix consisting of poly(9-vinylcarbazole) (PVK) (50 wt %) and (2- tert -butylphenyl-5-biphenyl-1,3,4-oxadiazole) (PBD) (50 wt %) radiation with maxima between 374 and 531 nm and characterized with Φ in the range of 8–12% was observed. They exhibited green or violet electroluminescence. The results confirmed the substantial role of aryl groups and the linker in the presented terpyridines in terms of their thermal, electrochemical, optical and electroluminescence properties. In addition, density functional theory (DFT) and time-dependent-density functional theory (TD-DFT) calculations were performed to provide an independent support and deeper insight into the experimental results. [ABSTRACT FROM AUTHOR]

A new nanocatalyst was synthesized by immobilization of 4′-(4-hydroxyphenyl)-2,2′:6′,2″-terpyridine/CuI complex on ferromagnetic nanoparticles through a surface modification (FMNPs@SiO2-TPy-Cu). This heterogeneous catalyst was characterized using various techniques including Fourier transform infrared and energy-dispersive X-ray spectroscopies, transmission and scanning electron microscopies, X-ray diffraction, vibrating sample magnetometry and thermogravimetric analysis. The resulting nanocatalyst presented excellent catalytic activity for the regioselective syntheses of 1,4-disubstituted 1,2,3-triazoles and thioethers. The thermally and chemically stable, benign and economical catalyst was easily recovered using an external magnet and reused in at least five successive runs without an appreciable loss of activity. [ABSTRACT FROM AUTHOR]

Three generations of metalated trigonal supramolecular architectures, so-called metallo-triangles, were assembled from terpyridine (tpy) complexes. The first generation (G1) metallo-triangles were directly obtained by reacting a bis(terpyridinyl) ligand with a 60° bite angle and ZnII ions. The direct self-assembly of G2 and G3 triangles by mixing organic ligands and ZnII, however, only generated a mixture of G1 and G2, as well as a trace amount of insoluble polymer-like precipitate. Therefore, a modular strategy based on the connectivity of ⟨tpy−Ru2+−tpy⟩ was employed to construct two metallo-organic ligands for the assembly of G2 and G3 Sierpiński triangles. The metallo-organic ligands LA and LB with multiple free terpyridines were obtained through Suzuki cross-coupling of the RuII complexes, and then assembled with ZnII or CdII to obtain high-generation metallo-triangular architectures in nearly quantitative yield. The G1-G3 architectures were characterized by NOESY and DOSY NMR spectroscopy, ESI-MS, TWIM-MS, and transmission electron microscopy. [ABSTRACT FROM AUTHOR]

New mono- and diruthenium, symmetrical and unsymmetrical complexes, bridged by a new cyclometalating 1,3,6,8-tetra(4-substituted-2-pyridyl)pyrene derivative containing the solubilizing group 2,2-dimethylpropyloxy, with the terminal 4′-phenyl-2,2′:6′,2′′-terpyridine ligands containing diethylamine and a 2-ethynyl-9,9-dioctylfluorene moiety, were synthesized and thoroughly characterized. Thermal studies show that the obtained complexes retain high thermal stability. Spectroscopic studies show the metal-to-ligand charge-transfer excitation. Further, electrochemical studies show delocalization of the electronic charge (mixed valance). In addition, density functional theory and time-dependent density functional theory calculations have provided more detail about the structural properties and a deeper understanding of the experimental results. All of the obtained results show the considerable differences between the mono- and diruthenium and symmetrical and unsymmetrical complexes. [ABSTRACT FROM AUTHOR]

Preparation of a series of terpyridyl ligands bearing different substituents recently led to the synthesis of new cobalt-bisterpyridyl complexes spanning over a wide range of redox potentials. In this work, we describe the catalytic properties of these complexes for the electroreduction of protons into hydrogen (hydrogen evolution reaction (HER)) in acetonitrile. The substituents of the ligands were found to greatly affect the catalytic performances of the systems, in terms of stability and overpotential. Interestingly, systems based on dimethylamino-terpyridine derivatives perform HER with high efficiency, low overpotential and excellent stability. Density functional theory calculations were used to provide insights into the reaction mechanism of HER catalyzed by these systems, highlighting the role of the ligand for proton activation. [ABSTRACT FROM AUTHOR]

A novel heterogeneous Pd catalyst was synthesized by anchoring Pd(II) onto 4′-(4-hydroxyphenyl)-2,2′:6′,2″-terpyridine-coated Fe3O4 (FMNPs@TPy-Pd). This catalyst has been demonstrated for the first time as a recoverable and reusable heterogeneous nanocatalyst in Suzuki and Heck cross-coupling reactions. The catalyst is very easy to handle and is environmentally safe and economical. FMNPs@TPy-Pd was characterized using transmission and scanning electron microscopies, X-ray diffraction, and Fourier transform infrared and energy-dispersive X-ray spectroscopies. [ABSTRACT FROM AUTHOR]

An asymmetric 'Pacman' metalloligand, [Zn(PXT)], which features a cofacial ZnII-porphyrin unit (P) covalently attached to a terpyridine (T) chelating group via a rigid xanthene (X) moiety has been prepared, and its interactions with several different trivalent LnIII cations (NdIII, GdIII, YbIII and LuIII) have been examined. The formation of 1:1 metal-ligand complexes was monitored by 1H NMR spectroscopy and corroborated by HRMS data. Solution-stability constants were determined by UV/Vis titration, and the resulting complexes with NdIII or YbIII demonstrated sensitised emission in the NIR region due to energy transfer from the ZnII-porphyrin donor to LnIII acceptor. The energy transfer was investigated by transient absorption techniques, which provided insight into the kinetics and efficiency of the antenna effect. [ABSTRACT FROM AUTHOR]

The design and construction of a novel terpyridine-based, dimetallic, 2D [4]triangulane architecture are reported. Synthesis of the metallotriangulane is achieved by multicomponent stepwise assembly of six bidentate and three tetradentate monomers. Characterization was accomplished by NMR spectroscopy, mass spectrometry and TEM microscopy. [ABSTRACT FROM AUTHOR]

New 2,2′:6′,2′′-terpyridine derivatives were prepared by Suzuki-Miyaura coupling of the corresponding 4,4′′-bis(nonaflate) with the appropriate boronic acid derivatives. The corresponding 4,4′′-diazido terpyridine derivative allowed a copper(I)-promoted click reaction with phenyl acetylene to provide the bis(triazolyl)-substituted terpyridine in excellent yield. For comparison, analogs or terpyridines with a central thiophene ring were synthesized by applying the well proven cyclocondensation reaction of the bis(β-ketoenamide) derived from 2,5-thiophenedicarboxylic acid. The UV/Vis spectra as well as the fluorescence spectra of these new compounds were recorded and compared with related heterocycles. [ABSTRACT FROM AUTHOR]

The scope of this short review is to point out how such an old reaction as the Kröhnke-type ring closure is still used nowadays to enable simple access to pyridines or polypyridines. Besides the usual Stille or Suzuki coupling reactions, which deal, respectively, with stannylated derivatives or boronic derivatives, the Kröhnke reaction can reach its target molecules with commercially available starting materials in a simple reaction medium without any special care. 1 Introduction 2 The Kröhnke Reaction 3 Applications 3.1 Catalysis 3.2 Materials 3.2.1 Dye-Sensitized Solar Cells 3.2.2 OLEDs and LECs 3.3 Biological Applications 3.3.1 Luminescent Probes 3.3.2 Chemosensors 3.3.3 Anticancer Compounds 3.3.4 Antimicrobial Activity 4 Miscellaneous 5 Summary and Outlook. [ABSTRACT FROM AUTHOR]

The synthesis and structure of thiacalix[4]monocrowns in1,3-alternateconfiguration substituted by terpyridyl fragments on the lower rim are being discussed. It has been shown that the number of oxyethylene units in oligoethylene glycol chain affects the distribution of the yields of the cross-linking products leading to either thiacalix[4]monocrowns or bisthiacalix[4]arenes. Their complexation ability towards alkali metal and lanthanide ions has been studied using liquid extraction and MALDI TOF MS, in addition to luminescent properties of ligands and their lanthanide complexes. The NMR titration data discovered the participation of both crown ether and terpyridyl fragment in the coordination of lanthanide cations. The fluorescent titration showed the nonlinear emission response to the amount of lanthanide ions. [ABSTRACT FROM AUTHOR]

The synthesis and characterisation of novel thioacetyl-functionalised terpyridine ligands and their ruthenium and rhodium complexes [Ru(tpy) 2 ](PF 6 ) 2 , [Rh(tpy) 2 ](PF 6 ) 3 , [Ru(phen)(tpy)Cl](PF 6 ), [Rh(phen)(tpy)Cl](PF 6 ) 2 (phen = phenanthroline; tpy = S-[ω-(2,2:6′,2″-terpyridin-4′-yl)phenoxy]alkyl ethanethioate) have been described. Ligands and complexes were characterised by 1 H NMR spectroscopy, mass spectrometry, elemental analysis and cyclic voltammetry data. The crystal structure of the complex [Rh(phen)(tpy)Cl](PF 6 ) 2 (phen = phenanthroline; tpy = 4′-phenyl-2,2′:6′,2″-terpyridine) ( 21 ), have been determined by X-ray crystallography. Complex 21 show a distorted octahedral geometry around the ruthenium centre. Antimicrobial activity toward Escherichia coli at concentrations as low as 5 μM was found for some of the studied complexes. For complexes [Rh(tpy C 6 H 4 O(CH 2 ) 8 SCOCH 3 ) 2 ](PF 6 ) 3 ( 19 ), [Rh(phen)(tpy C 6 H 4 O (CH 2 ) 8 SCOCH 3 )Cl](PF 6 ) 2 ( 31 ) and [Rh(phen)(tpy C 6 H 4 O (CH 2 ) 11 SCOCH 3 )Cl](PF 6 ) 2 ( 32 ), a strong inhibition of in vitro protein synthesis was observed using firefly luciferase. An investigation of cytotoxicity of the complexes against human embryonic kidney cells (HEK293 line) by the MTT assay demonstrates that the toxicity of all tested compounds is of similar magnitude, with IC 50 values of 3–30 μM. [ABSTRACT FROM AUTHOR]

Terpyridine and quaterpyridine-based complexes allow wide light harvesting of the solar spectrum. Terpyridines, with respect to bipyridines, allow for achieving metal-complexes with lower band gaps in the metal-to-ligand transition (MLCT), thus providing a better absorption at lower energy wavelengths resulting in an enhancement of the solar light-harvesting ability. Despite the wider absorption of the first tricarboxylate terpyridyl ligand-based complex, Black Dye (BD), dye-sensitized solar cell (DSC) performances are lower if compared with N719 or other optimized bipyridine-based complexes. To further improve BD performances several modifications have been carried out in recent years affecting each component of the complexes: terpyridines have been replaced by quaterpyridines; other metals were used instead of ruthenium, and thiocyanates have been replaced by different pinchers in order to achieve cyclometalated or heteroleptic complexes. The review provides a summary on design strategies, main synthetic routes, optical and photovoltaic properties of terpyridine and quaterpyridine ligands applied to photovoltaic, and focuses on n-type DSCs. [ABSTRACT FROM AUTHOR]

Single-chain nanoparticles can be obtained via single-chain folding assisted by intramolecular crosslinking reversibly or irreversibly. Single-chain folding is also an efficient route to simulate biomacromolecules. In present study, poly( N-hydroxyethylacrylamide-co-4′-(propoxy urethane ethyl acrylate)-2,2′:6′,2″-terpyridine) (P(HEAm-co-EMA-Tpy)) is synthesized via reversible addition fragmentation chain transfer polymerization. Single-chain folding and intramolecular crosslinking of P(HEAm-co-EMA-Tpy) are achieved via metal coordination chemistry. The intramolecular interaction is characterized on ultraviolet/visible spectrophotometer (UV-vis spectroscopy), proton nuclear magnetic resonance (1H NMR), and differential scanning calorimetry (DSC). The supramolecular crosslinking mediated by Fe2+ plays an important role in the intramolecular collapsing of the single-chain and the formation of the nanoparticles. The size and morphology of the nanoparticles can be controlled reversibly via metal coordination chemistry, which can be characterized by dynamic light scattering (DLS), transmission electron microscope (TEM), and atomic force microscope (AFM). [ABSTRACT FROM AUTHOR]

On the basis of an easy access to 2,2':6',2''-terpyridine derivatives bearing 6- and 6''-methyl groups, the functionalization of these substituents was investigated. The direct oxidation or bromination of the methyl groups was not feasible on larger scale; however, a two-step process employing oxidation to the pyridine N-oxides followed by acetic anhydride promoted rearrangement (Boekelheide reaction) furnished the corresponding terpyridine derivatives with 6- and 6''-acetoxymethyl groups in reasonable overall yields. These are excellent precursors for the synthesis of tetra- and pentadentate ligands, as demonstrated by several examples. This approach allowed access to a library of new functionalized 2,2':6',2''-terpyridine derivatives. [ABSTRACT FROM AUTHOR]

A series of metallo-supramolecular ring-in-ring structures was generated by assembling CdII ions and the multivalent terpyridine ligands ( L1-3) composed of one 60°-bent and two 120°-bent bis(terpyridine)s with varying alkyl linker lengths. The mechanistic study for the self-assembly process excluded an entropically templated pathway and showed that the intramolecularly complexed species is the key intermediate leading to ring-in-ring formation. The next-generation superstructure, a spiderweb, was produced in quantitative yield using the elongated decakis(terpyridine) ligand ( L5). [ABSTRACT FROM AUTHOR]

A tetrahedral shape-persistent molecule equipped with four terpyridine ligands can form an oligomeric structure upon complexation with metal ions, in which two terpyridine units are intermolecularly connected via a metal ion. The most interesting results were obtained upon binding of lanthanide ions, whose luminescence is sensitized by the ligand. In particular, dual luminescent probes were obtained upon concomitant complexation of two different lanthanide ions, such as EuIII and NdIII. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of novel sulfur-containing terpyridine ligands and their ruthenium and rhodium complexes [Ru(tpy) 2 ](PF 6 ) 2 , [Rh(tpy) 2 ](PF 6 ) 3 , [Ru(phen)(tpy)Cl](PF 6 ), [Rh(phen)(tpy)](PF 6 ) 2 (phen = phenanthroline; tpy = S-[4-(2,2:6′,2″-terpyridin-4′-yl)phenoxy]butyl ethanethioate or 4′-[4-(1,2-dithiolane-3-yl)butylcarboxy)phenyl]-2,2′:6′,2″-terpyridine) have been described. The complexes are redox-active, showing both metal-centered and ligand-centered processes. The data of electrochemical study confirm the chemisorption of complexes on the gold electrode surface. The antibacterial activity of the synthesized complexes was tested against two pathogens ( Micrococcus luteus and Pseudomonas aeruginosa ) by the well diffusion method. A biological study indicated that two complexes exhibit a good activity against M. luteus and the activity of symmetrical ruthenium complex [Ru(tpy-C 4 H 4 -O-C(O)-(CH 2 ) 4 -C 3 H 5 S 2 ) 2 ](PF 6 ) 2 is better than the activity of the commercially available antibiotics streptomycin and kanamycin. It was shown that the ruthenium terpyridine–phenanthroline complex [Ru(phen)(Tpy-C 6 H 4 -O-(CH 2 ) 4 -SCOCH 3 )Cl]PF 6 efficiently catalyzed the oxidation of triphenylphosphine to triphenylphosphine oxide and styrene to styrene oxide with iodosobenzene in mild conditions. [ABSTRACT FROM AUTHOR]

A new bis(terpyridine) derivative with a phenylacetylene framework was synthesized via a stepwise terpyridine construction strategy. The addition of ZnCl2to a solution of the bis(terpyridine) in chloroform resulted in UV/vis and1H NMR spectral changes because of complex formation. [ABSTRACT FROM PUBLISHER]

A heteroleptic ruthenium sensitizer ( DV56) bearing a terpyridine ligand with an appended phenylanthracene moiety was synthesized and extensively characterized. The physicochemical properties of the light-harvesting antenna were studied in solution and on sensitized TiO2 thin film electrodes using a variety of spectroscopic and photoelectrochemical techniques. Contact angle measurements suggest that the DV56-sensitized TiO2 films are hydrophilic. Raman measurements indicate chemisorption of the dye on the semiconducting surface. Electrochemical studies of the dye show that its first oxidation potential lies well below the I−/I3− redox potential, allowing easy regeneration. Moreover, its excited state oxidation potential lies above the TiO2 conduction band edge, permitting efficient electron injection from the photosensitizer into the semiconductor. I−/I3−-based liquid redox electrolyte dye-sensitized solar cells incorporating DV56-sensitized TiO2 photoelectrodes afford an overall power conversion efficiency of 3.75 %. [ABSTRACT FROM AUTHOR]

A versatile method for the synthesis of functionalized 2,2′:6′,2′′-terpyridines by assembly of the terminal pyridine rings is presented. The cyclization precursors-bis-β-ketoenamides-are prepared from 4-substituted 2,6-pyridinedicarboxylic acids and acetylacetone or its corresponding enamino ketone. Treatment with trimethylsilyl trifluoromethanesulfonate induces a twofold intramolecular condensation providing an efficient access to 4,4′′-di- and 4,4′,4′′-trifunctionalized 6,6′′-dimethyl-2,2′:6′,2′′-terpyridines. Using this method, hitherto unknown 4,4′′-bis(dimethylamino)- and 4,4′,4′′-tris(dimethylamino)terpyridines have been prepared that show remarkably high calculated Lewis basicities. [ABSTRACT FROM AUTHOR]

A highly efficient copper-catalyzed Csp-X (X = S, Se, Te) bond-forming reaction of terminal alkynes and diorganyl dichalcogenides has been developed. This transformation was realized through the use of copper(I) iodide as a catalyst, 4'-(4- methoxyphenyl)-2,2':6',2''-terpyridine as a ligand, and K3PO4 as a base. A variety of the functionalized substrates were found to react under these reaction conditions to provide products in good to excellent yields. [ABSTRACT FROM AUTHOR]

New thiacalix[4]arenes tetrasubstituted by terpyridyl fragments at the lower rims in the 1,3-alternate stereoisomeric form were synthesized. The molecules interact with Eu and Tb in the DMF solution to form highly luminescent nanoscale (21-26 nm) metal-organic structures with the 2: 1 metal-to-ligand stoichiometry and a narrow particle size distribution. [ABSTRACT FROM AUTHOR]

The synthesis of asymmetrically substituted 2,2′:6′,2′′-terpyridines is reported. First, palladium-catalyzed CH arylation of pyridine N-oxides with substituted bromopyridines gave 2,2′-bipyridine N-oxides, which were further arylated in a second step to form 2,2′:6′,2′′-terpyridine N-oxides. Yields of up to 77 % were obtained with N-oxides bearing an electron-withdrawing ethoxycarbonyl substituent in the 4-position. Pd(OAc)2 with either P( tBu)3 or P( o-tolyl)3 was used as the catalyst. Cyclometalated complexes derived from Pd(OAc)2 and these phosphines were also effective. K3PO4 as the base gave better results than K2CO3. Subsequent deoxygenation with H2 and Pd/C as the catalyst gave the asymmetrically substituted 2,2′:6′,2′′-terpyridines in near quantitative yield. This reaction sequence significantly reduces the number of steps required in comparison with known cross-coupling methods and therefore allows convenient and scalable access to substituted terpyridines. [ABSTRACT FROM AUTHOR]

A good fit: Interactions between A‐kinase anchoring proteins (AKAPs) and protein kinase A (PKA) play key roles in a plethora of physiologically relevant processes whose dysregulation causes or is associated with diseases such as heart failure. Terpyridines have been developed as α‐helix mimetics for the inhibition of such interactions and are the first biologically active, nonpeptidic compounds that block the AKAP binding site of PKA. [ABSTRACT FROM AUTHOR]

The two different coordination spheres afforded by Pacman architectures offer cooperativity derived from two different metal centers. A modular strategy is developed to produce a hetero-Pacman scaffold featuring a porphyrin and terpyridine for metal-ion binding. A double Suzuki reaction was employed to first attach a terpyridine moiety to a xanthene backbone and then attach a porphyrin. The new hetero-Pacman scaffold has been characterized and all building blocks have been isolated and structurally characterized. The principle objective to incorporate different metal centers was confirmed by isolating a trinuclear complex comprising two porphyrinic units and a bis(terpyridine)-iron unit. The compounds described herein expand the Pacman scaffold concept by allowing for the incorporation of a terpyridine-metal complex proximate to a porphyrin-cofactor active site for small-molecule activation. [ABSTRACT FROM AUTHOR]

Abstract: The novel octahedral copper(II) complexes with the second generation fluoroquinolone, norfloxacin and terpyridine derivatives were prepared and characterized. The antimicrobial efficiency of the complexes were tested on five different microorganisms and showed good biological activity. Viscosity measurement and absorption titration were employed to determine the mode of binding of complexes with DNA whereas the cleavage efficacy of the complexes towards pUC19 DNA was determined by electrophoresis in presence of ethidium bromide. SOD mimic behaviour was actively sought for clinical and mechanistic purposes under a nonenzymatic system (NBT/NADH/PMS), and was found to have good antioxidant activity. [Copyright &y& Elsevier]

Abstract: One step nickel-catalyzed electroreductive homocoupling among 2-bromopicolines and 2-bromopyridine has been investigated by our group in an undivided cell and using zinc or iron as sacrificial anode. In this work, it was developed mono and dihalopyridines coupling to obtain possible products from heterocoupling. A series of reactions were carried out in order to develop a synthetic method for the preparation of unsymmetrical 2,2′-bipyridines and 2,2′:6′,2″-terpyridines. Statistical yields (50%) were observed for 2-bromopyridines/2-bromo-6-methylpyridine heterocoupling. In a preliminary study devoted to terpyridines preparation, good results were obtained for 2,6-dihalopyridines homocoupling, affording 2,6-dichloro-2,2′-bipyridine (46%) and 2,6-dibromo-2,2′-bipyridine (56%), at controlled reaction time. At major reaction time, it was observed that the direct electroreduction of the 2,6′-dihalo-2,2′-bipyridines intermediates and 2,6″-dihalo-2,2′:6′,2″-terpyridines products on the cathode surface. A reasonable isolated product yield of 6,6″-dimethyl-2,2′:6′,2″-terpyridine (10%) was only observed in the reaction between 2,6-dichloropyridine and 2-bromo-6-methylpyridine (1:2). [Copyright &y& Elsevier]

As building blocks for metallo-supramolecular polymers, novel, unsymmetrical, monosubstituted bis-terpyridine derivatives with one electron-donating (OMe) or electron-withdrawing (CN or COOMe) group have been synthesized via the Suzuki- Miyaura cross-coupling reaction. This method is quick, efficient and suitable for the introduction of various substituents at the periphery of pyridine. [ABSTRACT FROM AUTHOR]

Abstract: We report a convenient single-flask methodology for the preparation of polyazatriaryl products with relevance to luminescence, catalysis, and pharmacology. The diborylation of 1,3-dibromobenzenes and double Suzuki–Miyaura coupling produces 1,3-diheteroarylbenzenes. Similarly, borylation of heteroaryl halides and double coupling to 2,6-dichloropyridine produces 2,6-diheteroarylpyridines. This methodology appears general in producing challenging polyheteroaryl targets as long as the boronic esters have no ortho heteroatoms and coupling avoids adjacent oxygens. [Copyright &y& Elsevier]

The synthesis and photophysical properties of several 6,6″ symmetrically substituted 4′-aryl-2,2′:6′,2″-terpyridine derivatives are reported herein. The UV-Vis spectra in acetonitrile as well as in dichloromethane show two intense bands in the UV areas 252-262 nm and 275-290 nm while the fluorescence emission spectra are only slightly influenced by chemical derivatization. [ABSTRACT FROM AUTHOR]

Organic ligands containing terpyridine and disulfide groupings linked between one another by a bonding -O(CH) ( n = 6, 12) fragment have been synthesized. Gold nanoparticles of mean size 1.8 nm modified with the indicated ligand were obtained by the method of Brust. By methods of electron spectroscopy and cyclic voltamperometry, the possibility of forming of coordinated compounds on the surface of gold nanoparticles modified by a terpyridine ligand, on interaction with Cu(MeCN)ClO has been shown. The obtained nanoparticles catalyze the oxidation of 2,4-di-tert-butylphenol into 3,3',5,5'-tetra(tert-butyl)biphenyl-2,2'-diol. [ABSTRACT FROM AUTHOR]

Abstract: The novel neutral mononuclear copper(II) complexes with the quinolone antibacterial drugs ciprofloxacin in the presence of the nitrogen donor heterocyclic ligand of terpyridine have been synthesized and characterized by elemental analysis, reflectance spectra, IR and mass spectroscopy. The antibacterial activities of the newly synthesized compounds were evaluated and correlated with their physicochemical properties. Results revealed that the tested compounds exhibited better inhibitory activities than the reference antibacterial quinolone drugs against Gram(+ve) and Gram(−ve) bacteria. The coordination compounds can act as catalysts for the dismutation of superoxide anion radicals (). The detection of the rate constant of the reaction of superoxide ion with nitro blue tetrazolium (NBT) is inhibited by superoxide dismutase (SOD). The interaction of the complex with DNA was investigated using viscosity, absorption titration and DNA melting temperature techniques. The results indicate that the complexes bind to DNA with intercalative mode and they have rather high DNA-binding constants. DNA-cleavage study showed better cleaving ability of the complexes compare to metal salt and standard drugs. [ABSTRACT FROM AUTHOR]

One-pot reactions to produce isomeric 4'-(pyridyl) 2,2':6',2''-terpyridine under moderate conditions are described using imidazolium-based ionic liquid and quaternary ammonium-based molten salts as solvent media. The use of eutectic molten salts as a reaction media proved effective in sequential aldol and Michael addition reactions, leading to substituted terpyridines. The desired product was obtained in reasonable yield via a simple, one-pot reaction. [ABSTRACT FROM AUTHOR]

The modular approaches towards 2,2′:6′,2′′-terpyridines and U-/S-shaped terpyridines are combined to yield a new family of ditopic ligands. Functionalized Kr�hnke-type terpyridines were used as key building blocks for the construction of hetero-bis(terpyr�idine)s. The described compounds might serve as new templates for the self-assembly towards new metallosupramolecular functional materials. [ABSTRACT FROM AUTHOR]

Abstract: Using the principle of crystal engineering, six metal-organic coordination polymers, [Cd(bdc)(3-pytpy)] n ·2nH2O (1), [Cd(bdc)0.5(3-pytpy)] n · n(ClO4) (2), Cd(ndc)0.5(3-pytpy)] n · n(ClO4) (3), [Zn(ndc)(3-pytpy)] n (4), [Cd(bqdc)(3-pytpy)] n (5), and [Zn(pam)(3-pytpy)] n ·2nH2O (6) (H2bdc=benzene-1,4-dicarboxylic acid, H2ndc=naphthalene-2,6-dicarboxylic acid, H2bqdc=2,2′-biquinoline-4,4′-dicarboxylic acid, H2pam=pamoic acid), were synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. Compounds 1–6 crystallize in the presence of organic-acid linkers as well as multi-functional N-donor ligand 4′-(3-pyridyl)-2,2′:6′,2′′-terpyridine (3-pytpy). In complexes 1, 4, 5, and 6, the dicarboxylate as bridging ligand connects metal atoms to form the main body of 1D zigzag chains for 1 and 4, nearly linear chain for 5 and helical chain for 6, while 3-pytpy as tridentate chelating ligand is just like lateral arm grafting on both sides of these chains. In complexes 2 and 3, both the dicarboxylate and 3-pytpy as bridging ligands connect metal atoms into 2D polymeric structure for 2 and 1D chain of alternating loops and rods for 3. The weak interactions such as hydrogen bonding and π···π stacking were investigated on the formation of superamolecular structures and the influence of organic acid on the formation of the final structures was discussed. In addition, the photoluminescent properties of 1–6 were also determined. [Copyright &y& Elsevier]

For the development of novel antitumor agents, we designed and synthesized terpyridines, and their biological activities were evaluated. Although most of the newly prepared terpyridines showed strong cytotoxicity against several human cancer cell lines, [2,2′; 6′, 2″]-terpyridine displayed the most significant cytotoxicity. [ABSTRACT FROM AUTHOR]