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In this work, five phenanthroline derivatives substituted with different methyl groups have been selected to synthesize β‐diketonate‐based europium complexes to check the influence of the substitutions on the degradation effect of those complexes in poly(methyl methacrylate) (PMMA) films. The photophysical properties of Eu(III) complexes, including absorbance, excitation, and emission have been carefully investigated in solution, solid‐state, and doped in PMMA film. In all these states, the complexes exhibit an impressive red emission at 614 nm with a high photoluminescence quantum yield of up to 85 %. The films have been exposed under outdoor, indoor, and dark storage stability lifetime conditions for 1200 hours. The photoluminescence measurements recorded every 400, 800, and 1200 hours demonstrated that the film containing europium complex with phenanthroline ligand substituted by a high number of methyl groups (Eu(TTA)3L5) showed good photoluminescent stability in indoor and dark conditions, and exhibited better resistance to degradation in outdoor conditions compared to other complexes. This study has proved that phenanthroline ligands could be tuned chemically leading to better stability of those types of complexes in films which can be end‐used for future stable optoelectronic devices such as luminescent solar concentrators. [ABSTRACT FROM AUTHOR]

Manganese(II) complexes with phenanthroline derivatives modified with different substituents were synthesized and incorporated into Nafion layers covering the surfaces of glassy carbon electrodes and were studied electrochemically. Formal potentials and apparent diffusion coefficients were calculated and discussed. The suitability for electrocatalytic oxidation of ascorbic acid and glycolic acid was examined. The surfaces of modified electrodes were characterized using atomic force microscopy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Phenanthroline is an excellent and stable π‐electron acceptor with a large conjugated chromophore. Phenanthroline derivatives are widely used in adsorption, photodegradation, solar cells, biology, and so on. At present, there are still limited organic molecules utilized to efficiently photocatalyze reversible‐deactivation radical polymerization (RDRP). Therefore, the design of organic photocatalysts (OPCs) for RDRP remains a challenge. Herein, according to the strategy of combining the donor groups and weak acceptor groups, donor‐acceptor (D‐A) type OPCs based on phenanthroline were utilized for the first time in photoinduced electron transfer‐reversible addition‐fragmentation chain transfer (PET‐RAFT) polymerization. 1,10‐Phenanthroline‐5‐amine (Aphen) with a donor group‐amino was screened out for efficacious photo‐controlled radical polymerization under blue light for various monomers with conjugated and unconjugated structures with high monomer conversion and well‐defined narrow dispersity polymers (Đ < 1.20). Controllable homo‐polymers and block copolymers were successfully realized by chain extension reaction and block copolymerization of structurally diverse monomers. [ABSTRACT FROM AUTHOR]

1,10-Phenanthroline monohydrate (1,10-phen) is a fluorescent compound and a chemically versatile ligand that forms complexes with transition metals. The fluorescence quenching study has been done for 1,10-phen in the present study. We have synthesized Zirconium oxide (ZrO2) nanoparticles (NPs) by the modified precipitation method followed by post-hydrothermal synthesis. The synthesized NPs were subjected to x-ray diffraction, Scanning Electron Microscopy, Energy Dispersive x-ray, Ultraviolet-visible, and Fluorimetry characterization techniques. The effect of ZrO2 NPs on absorption and emission spectra of 1,10-phen has been investigated through spectroscopic technique. The excitation and emission wavelengths of 1,10-phen are observed to be 280 and 363 nm, respectively. Temperature studies to differentiate between static and dynamic quenching have been done through the Stern–Volmer plot. The type of fluorescence quenching mechanism is found to be collisional quenching. A study of the Forster resonance energy transfer theory on 1,10-phen was carried out with metal oxide ions. There is a considerable energy transfer between 1,10-phen and metal oxide ions. The present investigation can be aided in various applications, such as fluorescent biosensors and medical diagnosis. [ABSTRACT FROM AUTHOR]

In this work, we have compiled our research on lanthanide-based luminescent materials for use as down-shifter layers in photovoltaic (PV) mini-modules. The complexes we have prepared (C1–17), with formulas [Eu2(phen)2(bz)6] (C1), [Eu2(bphen)2(bz)6] (C2), [Eu(tta)3bphen] (C3), [Eu(bta)3pyz-phen] (C4), [Eu(tta)3pyz-phen] (C5), [Eu(bta)3me-phen] (C6), [Er(bta)3me-phen] (C7), [Yb(bta)3me-phen] (C8), [Gd(bta)3me-phen] (C9), [Yb(bta)3pyz-phen] (C10), [Er(tta)3pyz-phen] (C11), [Eu2(bz)4(tta)2(phen)2] (C12), [Gd2(bz)4(tta)2(phen)2] (C13), [EuTb(bz)4(tta)2(phen)2] (C14), [EuGd(bz)4(tta)2(phen)2] (C15), [Eu1.2Gd0.8(bz)4(tta)2(phen)2] (C16), and [Eu1.6Gd0.4(bz)4(tta)2(phen)2] (C17), can be grouped into three families based on their composition: Complexes C1–6 were synthesized using Eu3+ ions and phenanthroline derivatives as the neutral ligands and fluorinated β-diketonates as the anionic ligands. Complexes C7–11 were prepared with ligands similar to those of complexes C1–6 but were synthesized with Er3+, Yb3+, or Gd3+ ions. Complexes C12–17 have the general formula [M1M2(bz)4(tta)2(phen)2], where M1 and M2 can be Eu3+, Gd3+, or Tb3+ ions, and the ligands were benzoate (bz–), 2-thenoyltrifluoroacetone (tta–), and 1,10–phenanthroline (phen). Most of the complexes were characterized using X-ray techniques, and their photoluminescent properties were studied. We then assessed the impact of complexes in the C1–6 and C12–17 series on the EQE of PV mini-modules and examined the durability of one of the complexes (C6) in a climate chamber when embedded in PMMA and EVA films. This study emphasizes the methodology employed and the key findings, including enhanced mini-module efficiency. Additionally, we present promising results on the application of complex C6 in a bifacial solar cell. [ABSTRACT FROM AUTHOR]

Two novel silver(I) phenanthroline derivative complexes (P‐235 and P‐239) have been synthesized and characterized by IR, HPLC‐MS, and 1HNMR. The cytotoxicity of two complexes exhibited significant cytotoxicity against human breast cancer (MDA‐MB‐231) cell line (IC50 = 0.48 ± 0.01 and 0.12 ± 0.01 μM) and less toxicity than cisplatin by MTT assays. Furthermore, anticancer mechanistic studies showed that P‐235 and P‐239 induced G2/M phase cell cycle arrest to inhibit the growth of MDA‐MB‐231 cells. Flow cytometry analysis showed that MDA‐MB‐231 cells could be significantly induced to undergo apoptosis by P‐235 and P‐239. And P‐235‐ and P‐239‐induced apoptosis was linked with reactive oxygen species (ROS) production. Further study revealed that P‐235 and P‐239 cause mitochondrial membrane potential depolarization and destroy mitochondrial membrane potential. [ABSTRACT FROM AUTHOR]

Donor‐acceptor‐π bridge‐acceptor (D−A−π−A) motif dyes are promising dye sensitizers in dye‐sensitized solar cells (DSSCs). In this study, to strengthen with‐drawing electron force of the auxiliary electron acceptors(A) in D−A−π−A motif dye sensitizers, the metal complexes unit is be used as auxiliary electron acceptor(A) instead of organic electron‐withdrawing monomer. The four polymeric metal complexes were designed, synthesized, and characterized, which used metal complexes of phenanthroline derivatives as auxiliary acceptors (A), benzodithiophene‐dithiophene derivatives (BDTT) as donors (D), and 8‐hydroxyquinoline derivatives as π‐bridges and acceptors of the dye sensitizers, and have been used for dye sensitizers. Under AM 1.5 G (100 mW cm−2), the photovoltaic test results indicated that the short‐circuit photocurrent density (Jsc) of the DSSCs based four polymeric metal complexes are 11.26, 13.68, 14.42 and 15.57 mA cm−2 and power conversion efficiency (PCE) are 5.96 %, 7.83 %, 8.07 %, 9.28 % respectively. Both Jsc and PCE value of the four polymeric metal complexes increased in order. This may be due to the fact that larger radius of metal ion under the same change number can enhance the coordination bond and cause stronger electron‐withdrawing ability of auxiliary acceptor and stronger charge‐transfer ability between the donor and the acceptor, which results in higher Jsc and higher PCE of the polymeric complex dye sensitizer. [ABSTRACT FROM AUTHOR]

The interest in the use of copper as a metal scaffold for the development of novel chemotherapeutics has considerably grown in recent years. This is mainly due to the relatively lower toxicity of copper complexes with respect to platinum drugs (i.e., cisplatin), the different mechanisms of action, and the cheaper cost. In the last decades, hundreds of copper-based complexes were developed and screened as anticancer agents, with the antesignanus of all compounds being copper bis-phenanthroline [Cu(phen)2]2+ developed by D.S. Sigman in the late 1990s. In particular, copper(phen) derivatives have been shown high interest in their capacity to interact with DNA by nucleobase intercalation. Here, we report the synthesis and chemical characterization of four novel copper(II) complexes functionalised with phenanthroline derivatives containing biotin. Biotin, also known as Vitamin B7, is involved in a series of metabolic processes, and its receptors are often overexpressed in many tumour cells. A detailed biological analysis including cytotoxicity in 2D and 3D, cellular drug uptake, DNA interaction, and morphological studies are discussed. [ABSTRACT FROM AUTHOR]

The electrochemistry and photophysics of the Pt(II) complexes [Pt(naphen)(X)] (Hnaphen = naphtho[1,2-b][1,10]phenanthroline, X = Cl or C≡CPh) containing the rigid tridentate C^N^N-coordinating pericyclic naphen ligand was studied alongside the complexes of the tetrahydro-derivative [Pt(thnaphen)(X)] (Hthnaphen = 5,6,8,9-tetrahydro-naphtho[1,2-b][1,10]phenanthroline) and the N^C^N-coordinated complex [Pt(bdq)(Cl)] (Hbdq = benzo[1,2-h:5,4-h']diquinoline. The cyclic voltammetry showed reversible reductions for the C^N^N complexes, with markedly fewer negative potentials (around −1.6 V vs. ferrocene) for the complexes containing the naphen ligand compared with the thnaphen derivatives (around −1.9 V). With irreversible oxidations at around +0.3 V for all of the complexes, the naphen made a difference in the electrochemical gap of about 0.3 eV (1.9 vs. 2.2 eV) compared with thnaphen. The bdq complex was completely different, with an irreversible reduction at around −2 V caused by the N^C^N coordination pattern, which lacked a good electron acceptor such as the phenanthroline unit in the C^N^N ligand naphen. Long-wavelength UV-Vis absorption bands were found around 520 to 530 nm for the C^N^N complexes with the C≡CPh coligand and were red-shifted when compared with the Cl derivatives. The N^C^N-coordinated bdq complex was markedly blue-shifted (493 nm). The steady-state photoluminescence spectra showed poorly structured emission bands peaking at around 630 nm for the two naphen complexes and 570 nm for the thnaphen derivatives. The bdq complex showed a pronounced vibrational structure and an emission maximum at 586 nm. Assuming mixed 3LC/3MLCT excited states, the vibronic progression for the N^C^N bdq complex indicated a higher LC character than assumed for the C^N^N-coordinated naphen and thnaphen complexes. The blue-shift was a result of the different N^C^N vs. C^N^N coordination. The photoluminescence lifetimes and quantum yields ΦL massively increased from solutions at 298 K (0.06 to 0.24) to glassy frozen matrices at 77 K (0.80 to 0.95). The nanosecond time-resolved study on [Pt(naphen)(Cl)] showed a phosphorescence emission signal originating from the mixed 3LC/3MLCT with an emission lifetime of around 3 µs. [ABSTRACT FROM AUTHOR]

With the development of green chemistry, it is necessary to extract minor actinides from toxic high-level liquid waste. Hence, we need to explore the nature of bonding between ligands and actinide cations in order to design excellent ligands. In the present work, we systematically investigate the potential separation ability of typical tetradentate ligands (1,10-phenanthroline-2,9-diyl)bis((1H-1,2,4-triazol-1-yl)methanone) (Ltriazol), (1,10-phenanthroline-2,9-diyl)bis((1H-pyrazol-1-yl)methanone) (Lpyrazol) and (1,10-phenanthroline-2,9-diyl)bis((1H-pyrrol-1-yl)methanone) (Lpyrrol) for trivalent lanthanides and actinides through quasi-relativistic density functional theory (DFT). The coordination number of the possible extracted complexes of 1 : 1 type AnL(NO3)3 and 1 : 2 type [AnL2(NO3)]2+ (An = Np, Pu, Am, Cm; L = Ltriazol, Lpyrazol, Lpyrrol) is 10 in a nitric acid environment. Both the electrostatic potential and natural atomic charge analyses of the ligands show that Lpyrazol has stronger ability to attract actinide cations than Ltriazol and Lpyrrol, which may be caused by different amide substituents. The QTAIM (quantum theory of atoms in molecules) and IRI (interaction region indicator) analysis validate that there is a weak covalent interaction between the ligand and the actinide metal ion. The analyses including geometry, WBI (Wiberg bond index), NBO (natural bond orbital), and thermodynamics suggest that the interaction between the ligand and actinide cations gradually decreased from Np to Cm. Our theoretical study may contribute to a better understanding of the nature and law of bonding between actinide ions and ligands, and pave the way for designing robust ligands for in-group separation of transuranic complexes in the future. [ABSTRACT FROM AUTHOR]

The synthesis of 1,4-phenylene-bis(N-1,10-phenanthrolynylmethanimine) and its Pd (II) complex is described. Their structures were confirmed using FTIR, 1H-NMR, MS, UV-Vis and ICP-OES. Based on these analysis, it can be concluded that the obtained complex is a linear coordination polymer. [ABSTRACT FROM AUTHOR]

The influence of hydrogen bonds in model intercalated systems between guanine‐cytosine and adenine‐thymine DNA base pairs (bps) was analyzed with the popular intercalator 1,10‐phenanthroline (phen) and derivatives obtained by substitution with OH and NH2 groups in positions 4 and 7. Semiempirical and Density Functional Theory (DFT) methods were used both including dispersion effects: PM6‐DH2, M06‐2X and B3LYP‐D3 along with the recently developed near linear‐scaling coupled cluster method DLPNO‐CCSD(T) for benchmark calculations. Our results given by QTAIM and non‐covalent interaction analysis confirmed the existence of hydrogen bonds created by OH and NH2. The trends in the energy decomposition analysis for the interaction energy, ΔEint, showed that the ΔEelstat contributions are equal or even a little bit higher than the values for ΔEdisp. Such important ΔEelstat attractive contribution comes mainly from the conventional hydrogen bonds formed by OH and NH2 functional groups with DNA not only with bps but specially with the sugar and phosphate backbone. This behavior is very different from that of phen and other classical intercalators that cannot form conventional hydrogen bonds, where the ΔEdisp is the most important attractive contribution to the ΔEint. The inclusion of explicit water molecules in molecular dynamics simulations showed, as a general trend, that the hydrogen bonds with the bps disappear during the simulations but those with the sugar and phosphate backbone remain in time, which highlights the important role of the sugar and phosphate backbone in the stabilization of these systems. [ABSTRACT FROM AUTHOR]

Hybrid photochromic materials (HPMs) have potential applications in numerous fields, such as display, protection, and information storage. The generation of HPMs with tunable photochromic performance is meaningful for the availability of smart photoresponsive materials. As a good platform, crystalline HPMs (CHPMs) provide possibilities to generate desirable products because of their synthetic tunability. To achieve this goal, how to introduce predesigned organic ligands as electron acceptors (EAs) into suitable electron donor (ED) systems is significant for yielding products with hybrid ED–EA structure triggering electron transfer (ET) after photo-stimulus. In this study, inserting protonated 1,10-phenanthroline (phen) (as EAs) and its monosubstituted derivatives 5-Cl-phen and 5-NH2-phen to the interchain voids of anionic halometallate units (as EDs) generated three CHPMs, namely [H-phen][BiCl4] (1), [H-5-Cl-phen][BiCl4]·H2O (2), and [H-5-NH2-phen][BiCl4]·H2O (3). The obtained products featured the same anionic inorganic chains with main differences in the protonated organic guests. As expected, compounds 1–3 displayed apparent photochromism because of the ET from the anionic chains to protonated organic units. Interestingly, the photochromic performance of complexes 1–3 could be tuned by inserting phenanthroline-derivative-guests. This research offers a universal way to engineer the photochromic performance of halometallate-based CHPMs under the guidance of the organic EA design. [ABSTRACT FROM AUTHOR]

• Three new complexes of tin(IV) based derivatives of 1,10-phenanthroline ligand have been synthetized and characterized. • Biological study of the three complexes was evaluated. • The results indicate that C2 is a good AChE inhibitor. • Molecular docking shows a satisfactory agreement with the experiment. • Based on the FMO localizations and Fukui functions, the C1 and C2 should have a similar behavior towards to the electrophilic and nucleophilic attacks. This work describes the synthesis, the crystal structure and the properties of three tin complexes derivatives of 1,10-phenanthroline, namely C 24 H 19 N 3 SnCl 2 (C1), C 24 H 20 N 4 SnCl 2 (C2) and C 27 H 22 N 4 SnCl 2 (C3). Their structures were elucidated by X-ray diffraction, IR and NMR (1H &13C). The in vitro anticholinesterase activity was investigated and compared to docking findings. The obtained results showed that the C2 complex presents the closest IC 50 value (10.99±0.34 μM) to that of galantamine (4.14±0.07 μM) and corroborated by the docking results, where C2 and C1 showed a score of 54.08, 51.32 for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity, respectively. The optimized structures obtained by density functional theory (DFT) gave comparable geometrical parameters around the tin(IV) cation of hexacoordination environment. The computed HOMO-LUMO gaps are large predicting stable compounds. The natural population analysis attributes negative charges of chlorine, carbon and nitrogen atoms directly bound to the tin(IV) cation. However, the natural charges of tin(IV) of +1.63 in both C1 and C2 compounds are lower than +1.74 calculated for C3, suggesting different electron transfers. The FMOs localizations and Fukui functions predict that C1 and C2 behave differently from C3 with regard to the reactivity towards protein targets, in agreement with the experimental data and the molecular docking results. [Display omitted] [ABSTRACT FROM AUTHOR]

A library of eleven cationic gold(III) complexes of the general formula [(C C)Au(N N)]+ when C C is either biphenyl or 4,4'‐ditertbutyldiphenyl and N N is a bipyridine, phenanthroline or dipyridylamine derivative have been synthesized and characterized. Contrasting effects on the viability of the triple negative breast cancer cells MDA‐MB‐231 was observed from a preliminary screening. The antiproliferative activity of the seven most active complexes were further assayed on a larger panel of human cancer cells as well as on non‐cancerous cells for comparison. Two complexes stood out for being either highly active or highly selective. Eventually, reactivity studies with biologically meaningful amino acids, glutathione, higher order DNA structures and thioredoxin reductase (TrxR) revealed a markedly different behavior from that of the well‐known coordinatively isomeric [(C N C)Au(NHC)]+ structure. This makes the [(C C)Au(N N)]+ complexes a new class of organogold compounds with an original mode of action. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of a phenanthroline and neomycin conjugate (7). Compound 7 binds to a human telomeric G‐quadruplex (G1) with a higher affinity compared with its parent compounds (phenanthroline and neomycin), which is determined by several biophysical studies. Compound 7 shows good selectivity for G‐quadruplex (G4) DNA over duplex DNA. The binding of 7 with G1 is predominantly enthalpy‐driven, and the binding stoichiometry of 7 with G1 is one for the tight‐binding event as determined by ESI mass spectrometry. A plausible binding mode is a synergistic effect of end‐stacking and groove interactions, as indicated by docking studies. Compound 7 can inhibit human telomerase activity at low micromolar concentrations, which is more potent than previously reported 5‐substituted phenanthroline derivatives. [ABSTRACT FROM AUTHOR]

In the present work, the stability constants of copper(II) complexes with 1,10-phenanthroline (phen), its methyl derivatives [4-methyl-1,10-phenanthroline (4-mphen) and 4,7-dimethyl-1,10-phenanthroline (dmphen)] and L-tryptophan (trp) were investigated using potentiometric method in 0.1 mol⋅L−1 KCl aqueous ionic media at 298.15 K, 308.15 K and 318.15 K. 'BEST' software package was applied to the potentiometric data for the calculation of the protonation constants of the ligands and the stability constants of the copper(II) binary and ternary complexes. The concentration distributions of the various complex species formed in solution were also evaluated as a function of pH using the 'SPE' software package. The thermodynamic parameters, enthalpy change (ΔH°), entropy change (ΔS°) and Gibbs energy change (ΔG°) were determined from the stability constants using Gibbs and van't Hoff equations. The complexation of copper(II) with the ligands in this work is spontaneous, exothermic and favourable at lower temperatures. [ABSTRACT FROM AUTHOR]

With 2-thenoyltrifluoroacetone (tta) as the first ligand and phenanthroline derivatives as the second ligand, two europium(III) complexes, Eu(tta)3L1 (L1 = 11-nitrodipyrido[3,2-a:2',3'-c]phenazine) (1) and Eu(tta)3L2 (L2 = 11-methoxydipyrido[3,2-a:2',3'-c]phenazine) (2), have been synthesized and their structures were characterized by NMR and single-crystal X-ray crystallography. The two complexes exhibited red emissions that belonged to 5D0→7Fj (j = 0-4) transitions of Eu in different solutions and solid state. Complex 2 with the electron-donating group showed preferable luminous properties to that of complex 1 with the electron-withdrawing group. Moreover, complex 2 displayed much longer lifetimes, higher quantum yields and better CIE color coordinates corresponding to pure red in color (x = 0.67, y = 0.33). In addition, the two complexes had strong intracellular luminescence, which indicated that they could be employed in luminescence imaging of living cells. [ABSTRACT FROM AUTHOR]

Three cationic heteroleptic iridium(III) complexes [Ir(piq)2(N^N)]+ (where piq refers to 1-phenylisoquinoline and N^N represents the fluorenyl-substituted phenanthroline (phen, 1), dipyrido-[3,2-a:2′,3′-c]phenazine (dppz, 2) and benzo[i]dipyrido[3,2-a:2′,3′-c]phenazine (dppn, 3)) were synthesized and their singlet and triplet excited-state characteristics were investigated via spectroscopic methods and theoretical calculations. The electronic absorption spectra of 1–3 in toluene all featured strongly absorbing ligand-center 1π,π* transitions below 380 nm, broad and intense diimine ligand-localized 1ILCT (intraligand charge transfer)/1π,π* transitions at 380–450 nm, weaker 1LLCT (ligand-to-ligand charge transfer)/1MLCT (metal-to-ligand charge transfer) transitions at 450–520 nm, and very weak spin-forbidden 3LLCT/3MLCT/3π,π* transitions at 550–680 nm. Variations of the core diimine ligand from phen to dppz caused a slight red-shift of the absorption bands at <450 nm for 2 compared to that of 1; while changing the core diimine ligand to dppn in 3 induced a more pronounced red-shift of the bands at 380–680 nm compared to those of 1 and 2. All three complexes exhibited structured room-temperature phosphorescence maximized at 590 nm and broad triplet excited-state absorption at 450–800 nm in toluene. However, the emission quantum yield of 3 was more than two orders of magnitude lower than those of 1 and 2 in toluene because the emitting state of 3 was the 2nd triplet excited state (T2). The nature of the lowest triplet excited state (T1) in toluene varied from the piq ligand localized 3π,π* mixed with some 3MLCT/3LMCT (ligand-to-metal charge transfer) characters in 1 and 2 to dppn ligand-based 3π,π*/3ILCT configuration in 3. The different nature of the T1 state in 3 resulted in a much stronger transient absorption (TA) at ca. 540 nm and 600–800 nm with a much longer TA lifetime (∼23 μs). In addition, the T1 state varied from pig ligand-localized 3π,π*/3MLCT/3LMCT in toluene to dppz localized 3π,π*/3ILCT state in CH3CN for 2, which resulted in a shorter triplet lifetime, reduced emission quantum yield, but stronger TA signals in the NIR regions for 2 in CH3CN. Because of the strong triplet excited-state absorption of 1–3 at 532 nm, all three complexes manifested strong reverse saturable absorption (RSA) at 532 nm, with the RSA trend following 3 > 2 > 1. Fluorenyl substitution not only enhanced the RSA at 532 nm for 2 and 3, but also made them potential broadband reverse saturable absorbers. [ABSTRACT FROM AUTHOR]

New 7-aryl(hetaryl)-9,10-dihydro-7H-cyclopenta[b][1,7]phenanthrolin-8(11H)-ones have been synthesized by three-component condensation of quinolin-5-amine with cyclopentane-1,3-dione and aldehydes of the aromatic and heteroaromatic series. [ABSTRACT FROM AUTHOR]

We report the design, synthesis and biological studies on a group of mixed ligand Fe(III) complexes as anti-cancer drug candidates, namely their interaction with DNA, cytotoxicity and mechanism(s) of action. The aim is to obtain stable, efficient and selective Fe-complexes to be used as anti-cancer agents with less damaging side effects than previously reported compounds. Five ternary Fe(III) complexes bearing a tripodal aminophenolate ligand L2−, H 2 L = N , N -bis(2-hydroxy-3,5-dimethylbenzyl)- N -(2-pyridylmethyl)amine, and different aromatic bases NN = 2,2′-bipyridine [Fe(L)(bipy)]PF 6 (1), 1,10-phenanthroline [Fe(L)(phen)]PF 6 (2), or a phenanthroline derivative co-ligand: [Fe(L)(amphen)]NO 3 (3), [Fe(L)(amphen)]PF 6 (3a), [Fe(L)(Clphen)]PF 6 (4), [Fe(L)(epoxyphen)]PF 6 (5) (where amphen = 1,10-phenanthroline-5-amine, epoxyphen = 5,6-epoxy-5,6-dihydro-1,10-phenanthroline, Clphen = 5-chloro-1,10-phenanthroline) and the [Fe(L)(EtOH)]NO 3 (6) complex are synthesized. The compounds are characterized in the solid state and in solution by elemental analysis, ESI-MS, magnetic susceptibility measurements and FTIR, UV–Vis, 1H and 13C NMR and fluorescence spectroscopies. [Fe(phen)Cl 3 ] and [Fe(amphen)Cl 3 ] were also prepared for comparison purposes. Spectroscopic binding studies indicate groove binding as the main interaction for most complexes with DNA, and for those containing amphen a B- to Z-DNA conformational change is proposed to occur. As determined via MTT analysis all compounds 1 – 6 are cytotoxic against a panel of three different cell lines (HeLa, H1299, MDA-MB-231). For selected compounds with promising cytotoxic activity, apoptosis was evaluated using cell and DNA morphology, TUNEL, Annexin V/7AAD staining and caspase3/7 activity. The compounds induce oxidative DNA damage on plasmid DNA and in cell culture as assessed by 8-oxo-Guanine and γH2AX staining. Comet assay confirmed the presence of genomic damage. There is also increased reactive oxygen species formation following drug treatment, which may be the relevant mechanism of action, thus differing from that normally assumed for cisplatin. The Fe(III)-complexes were also tested against strains of M. Tuberculosis (MTb), complex 2 depicting higher anti -MTb activity than several known second line drugs. Hence, these initial studies show prospective anti-cancer and anti-MTb activity granting promise for further studies. Image 1 • Novel Fe(III)-aminophenolate-phenanthroline complexes were obtained. • These new Fe(III)-complexes are cytotoxic against several cancer cells. • The Fe(III)-complexes trigger ROS accumulation and DNA damage. • The mode of cell death is apoptosis via caspase activation. [ABSTRACT FROM AUTHOR]

Nine new lanthanide coordination polymers, namely, [La 2 (MPIP) 2 (1,3-bdc) 3 ] n ‧5 n H 2 O (1) [Nd 2 (MPIP) 2 (1,3-bdc) 3 ] n ‧7 n H 2 O (2) , [Yb 2 (MPIP)(1,3-bdc) 3 ] n (3) , [Eu 2 (MPIP) 2 (1,3-bdc) 2 (CH 3 COO) 2 ] n (4) , [Ln 2 (MPIP) 2 (1,3-bdc) 2 (NO 3) 2 ] n ‧3 n H 2 O (Ln = Tb (5), Gd (6)), [Ln 2 (MPIP) 2 (1,3-bdc) 3 ] n ‧2 n H 2 O (Ln = Dy (7), Ho (8), Er (9)), MPIP = 2-(3-methylphenyl)imidazo(4,5-f)(1,10)-phenanthroline, H 2 (1,3-bdc) = benzene-1,3-dicarboxylic acid) have been synthesized under hydrothermal or solvothermal conditions and characterized by IR spectra, elemental analyses, powder X-ray diffraction and single crystal X-ray diffraction. Compounds 1 – 9 features 1D or 2D lanthanide isophthalate structures bearing large conjugated imidazophenanthroline derivative ligands. The thermal stabilities and luminescence properties of compounds 1 – 9 were investigated. Based on fluorescence sensing behavior, compounds 4 and 5 display a highly sensitive response toward Fe3+ ion through significant fluorescence quenching. Meanwhile, compound 5 can be used as an indicator to detect acidic and alkali environments. The white light emission was studied by heterogeneous physical mixing components of compounds 1 , 4 and 5. Nine new lanthanide coordination polymers based on 2-(3-methylphenyl)imidazo-(4,5-f)(1,10)-phenanthroline and benzene-1,3-dicarboxylic acid have been successfully synthesized. Compounds 1 – 9 exhibit a 1D or 2D lanthanide isophthalate structures bearing large conjugated imidazophenanthroline derivative ligands. Compounds 4 and 5 can be potential crystalline materials for detecting Fe3+ ion. Meanwhile, compound 5 can be used as an indicator to detect acid and alkali environments. In addition, white-light emission was obtained by heterogeneous physical mixing components of compounds 1 , 4 and 5. Image 1 [ABSTRACT FROM AUTHOR]

• Red emitting [Ln(acac) 3 (Br 2 -phen)] [Ln: Sm(III) and Eu(III)] complexes were synthesized. • Short contacts and their contribution in crystal packing were analyzed. • Detailed photophysical properties of complexes were analyzed. • Eu(III) complex showed large stimulated emission cross-section (σ (0→2) = 1.27 × 10−20 cm2). Two new octa-coordinated red emitting complexes of the type [Ln(acac) 3 (Br 2 -phen)] [acac: acetylacetonate, Br 2 -phen: 4,7-dibromo-1,10-phenanthroline, Ln: Sm(III) and Eu(III)] have been synthesized and characterized. Single crystal X-ray diffraction (SCXD) of [Eu(acac) 3 (Br 2 -phen)] and [Eu(acac) 3 (H 2 O) 2 ](H 2 O) revealed distorted square antiprism structure for both complexes. 2D fingerprint plots and Hirshfeld surface analyses signify important interactions in crystal packing [H⋯H (72.2%), O⋯H/H⋯O (18.9%) and C⋯H/H⋯C (6.7%) contacts for [Eu(acac) 3 (H 2 O) 2 ](H 2 O), while [Eu(acac) 3 (Br 2 -phen)] showed H⋯H (40.5%), Br⋯H/H⋯Br (12.9%) and O⋯H/H⋯O (6.5%)] contacts]. Photophysical measurements gave quantum yield (Q L n L) of 1.1 and 13% with corresponding luminescence lifetime (τ obs) of 38.76 ± 0.61 μs and 790 ± 1.53 μs for [Sm(acac) 3 (Br 2 -phen)] and [Eu(acac) 3 (Br 2 -phen)], respectively. We have further evaluated photophysical properties of [Eu(acac) 3 (Br 2 -phen)] theoretically from the optimized sparkle structure and steady-state emission spectrum of Eu(III) complex. The intramolecular energy transfer (W ET) and back-energy transfer (W BT) rate predicted from the calculated singlet (S 1) and triplet (T 1) levels to the emissive 5D 1 and 5D 0 states for Eu(III) follow the path S 0 → S 1 → T 1 → 5D 1 → 5D 0 → 7F 0,4. The Eu(III) complex showed large stimulated emission cross-section (σ (0→2) = 1.27 × 10−20 cm2) similar to Nd-glass laser (1.6–4.5 × 10−20 cm2) and offers promise for high-power laser medium. [ABSTRACT FROM AUTHOR]

Heteroleptic copper(I) complexes combining phenanthroline derivatives (NN) and chelating bisphosphine ligands (PP) are an important class of luminescent materials for various applications. Although thermodynamically stable, [Cu(NN)(PP)]+ derivatives are also kinetically unstable. As a result, a dynamic ligand‐exchange reaction is often observed in solution, leading to a dynamic mixture of heteroleptic and homoleptic complexes. To prevent the formation of the homoleptic species, macrocyclic phenanthroline ligands have been used for the preparation of [Cu(NN)(PP)]+ pseudorotaxanes. The topological constraint resulting from the macrocyclic structure of the NN ligand drives the thermodynamic equilibrium towards the exclusive formation of the heteroleptic complex as long as the macrocycle is large and flexible enough to allow for the threading of the PP ligand. Conversely, when the threading is prevented by steric constraints, unprecedented copper(I) complexes with a trigonal coordination geometry are obtained. These results are summarized in the present concept article. Macrocyclic phenanthroline ligands have been used for the preparation of [Cu(NN)(PP)]+ pseudorotaxanes (NN=phenantroline derivative; PP=bisphosphine). Topological constraint drives the thermodynamic equilibrium towards the exclusive formation of the heteroleptic complex as long as the macrocycle is large and flexible enough to allow for the threading of the PP ligand. Conversely, when the threading is prevented by steric constraints, unprecedented copper(I) complexes are obtained. [ABSTRACT FROM AUTHOR]

Abstract Four newly-synthetized styryl-phenanthroline derivatives were found to exhibit great acidochromism starting from neutral pH values down to negative H 0. The aqueous solution of all of the four molecules features a yellow color at nearly neutral pH, but when the acidity of the solution increases, the color changes and, depending on the compound, an orange, pink, purple or colorless hue is observed. Spectrophotometric and fluorimetric titrations were performed to describe the changes in the spectral properties of the molecules with pH. The huge acidochromic shifts shown by these molecules come from the protonation of the nitrogen atoms of the central phenanthroline rings or those of the dimethylamino or diphenylamino side substituents. Thanks to 1H NMR titrations, quantum-mechanical calculations and femtosecond-resolved excited state absorption, a full characterization of the differently protonated forms in terms of protonation sites, spectral and photophysical properties, is reported. These features thus make the molecules' chromophores suitable candidates for applications as acidochromic probes. Graphical abstract Excellent acidochromism exhibited by one of the investigated phenanthroline-derivatives from H 0 = −1 to pH = 9. Image 1 Highlights • Four styryl phenanthroline derivatives show great acidochromism. • Huge spectral shifts are brought about by multiple protonations. • The color of the solutions varies markedly upon protonation. • The protonation state of the molecules rules the entity of the excited state ICT. • Potential applicability as efficient pH probes in biological systems. [ABSTRACT FROM AUTHOR]

Reactions of 1,10‐phenanthroline (phen) and 2‐(3,4‐dichlorophenyl)acetic acid (dcaH) with Mn(CO3) (M = LiI, NaI and MgII; n = 1 and 2) in MeOH yield the mononuclear lithium complex aqua[2‐(3,4‐dichlorophenyl)acetato‐κO](1,10‐phenanthroline‐κ2N,N′)lithium(I), [Li(C8H5Cl2O2)(C12H8N2)(H2O)] or [Li(dca)(phen)(H2O)] (1), the dinuclear sodium complex di‐μ‐aqua‐bis{[2‐(3,4‐dichlorophenyl)acetato‐κO](1,10‐phenanthroline‐κ2N,N′)sodium(I)}, [Na2(C8H5Cl2O2)2(C12H8N2)2(H2O)2] or [Na2(dca)2(phen)2(H2O)2] (2), and the one‐dimensional chain magnesium complex catena‐poly[[[diaqua(1,10‐phenanthroline‐κ2N,N′)magnesium]‐μ‐2‐(3,4‐dichlorophenyl)acetato‐κ2O:O′] 2‐(3,4‐dichlorophenyl)acetate monohydrate], {[Mg(C8H5Cl2O2)(C12H8N2)(H2O)2](C8H5Cl2O2)·H2O}n or {[Mg(dca)(phen)(H2O)2](dca)·H2O}n (3). In these complexes, phen binds via an N,N′‐chelate pocket, while the deprotonated dca− ligands coordinate either in a monodentate (in 1 and 2) or bidentate (in 3) fashion. The remaining coordination sites around the metal ions are occupied by water molecules in all three complexes. Complex 1 crystallizes in the triclinic space group P with one molecule in the asymmetric unit. The Li+ ion adopts a four‐coordinated distorted seesaw geometry comprising an [N2O2] donor set. Complex 2 crystallizes in the triclinic space group P with half a molecule in the asymmetric unit, in which the Na+ ion adopts a five‐coordinated distorted spherical square‐pyramidal geometry, with an [N2O3] donor set. Complex 3 crystallizes in the orthorhombic space group P212121, with one Mg2+ ion, one phen ligand, two dca− ligands and three water molecules in the asymmetric unit. Both dcaH ligands are deprotonated, however, one dca− anion is not coordinated, whereas the second dca− anion coordinates in a bidentate fashion bridging two Mg2+ ions, resulting in a one‐dimensional chain structure for 3. The Mg2+ ion adopts a distorted octahedral geometry, with an [N2O4] donor set. Complexes 1–3 were evaluated against urease and α‐glucosidase enzymes for their inhibition potential and were found to be inactive. Reactions of 1,10‐phenanthroline (phen) and 2‐(3,4‐dichlorophenyl)acetic acid (dcaH) with Mn(CO3) (M = LiI, NaI and MgII; n = 1 and 2) in MeOH yield the mononuclear lithium complex, the dinuclear sodium complex and the one‐dimensional chain magnesium complex. In these complexes, phen binds via an N,N′‐chelate pocket, while the deprotonated dca− ligands coordinate either in a monodentate or bidentate fashion. [ABSTRACT FROM AUTHOR]

Abstract Two new donor-acceptor-donor (D-A-D) small molecules, named L1 and L2 , based on furan-fused and fluorinated furan-fused 1,10-phenanthroline as electron-acceptor units and 4-(bis(4-methoxyphenyl)amino)phenyl as electron-donor units, were designed and synthesized. The photophysical and electrochemical properties were studied. The results are compared and discussed with respect to the influence of attached fluorine and solvent polarity. L1 and L2 emit intense blue light in non-polar solvent with high photoluminescence (PL) quantum yield (η PL) of 1 for L2. The absorption and PL spectra of L2 with attached fluorine atoms are red-shifted compared with those of L1. Red shifts of PL maxima are observed with the increasing solvent polarity in solution spectra for both L1 and L2. η PL values in solutions decrease as solvent polarity increases and the η PL difference for L1 and L2 in solution is not so pronounced as for L1 and L2 thin films. In addition, the effect of protonation on the nitrogen atoms of phenanthroline in thin films is shown. L1 and L2 were tested in the light-emitting devices and their electroluminescent properties are also reported. The preliminary results show L1 and L2 are almost pure white emitter and greenish blue emitter, respectively. Highlights • Two D-A-D small molecules, L1 and L2 , based furan-fused 1,10-phenanthroline, were designed and synthesized. • The effects of protonation and deprotonation on the nitrogen atoms of phenantroline was studied. • L1 and L2 were tested as non-doped active layers of OLED, showing that L1 and L2 are nearly white and greenish blue emitters. [ABSTRACT FROM AUTHOR]

Graphical abstract A kinetic study of the regioselective oxygen exchange of the axial CO ligands in the [Re(bpy)(CO) 4 ] cation was carried out via in situ infrared spectroscopy. The reaction is proposed to proceed by way of a hydroxycarbonyl intermediate with a Δ H ≠ of 49.9 kJ/mol. Abstract [Re(bpy)(CO) 4 ][OTf] 1 and [Re(phen)(CO) 4 ][BF 4 ] 2 (bpy = 2,2′-bipyridine and phen = 1,10-phenanthroline) in acetonitrile have been shown to undergo oxygen atom exchange reactions with 18-oxygen labelled water regioselectivity at the axial CO ligands. This process is proposed to proceed via an hydroxycarbonyl intermediate, with a Δ H ≠ = 49.9 ± 4.1 kJ/mol in the case of complex 1. [ABSTRACT FROM AUTHOR]

Graphical abstract Reactions of diphosphine and diimine ligands with AgCF 3 SO 3 under different reaction conditions gave rise to six complexes with different structures. The representative one-dimensional coordination polymer {[Ag(dppe)(dmp)](CF 3 SO 3)·(CH 3 OH)·(H 2 O)} n exhibited good stability and excellent catalytic activity toward the photodegradation of a spectrum of common organic dyes in water under UV light irradiation. Abstract Six new silver(I) complexes with diphosphine ligands and 1,10-phenanthroline derivatives are named by [Ag 2 (dppe)(dicnq) 2 ](CF 3 SO 3) 2 (1), [Ag 2 (dppp) 2 (dicnq) 2 ](CF 3 SO 3) 2 (2), [Ag 2 (dppb) 2 (dicnq) 2 ](CF 3 SO 3) 2 (3), [Ag(DPEphos)(dicnq)]CF 3 SO 3 (4), {[Ag(dppe)(dmp)](CF 3 SO 3)·(CH 3 OH)·(H 2 O)} n (5), [Ag 2 (dppp) 2 (dmp) 2 ](CF 3 SO 3) 2 ·(H 2 O) (6), (dppe = 1,2-bis(diphenylphosphino)ethane, dppp = 1,3-bis(diphenylphosphino)propane, dppb = 1,4-bis(diphenylphosphino)butane, DPEphos = bis[2-(diphenylphosphanyl)phenyl]ether, dmp = 2,9-dimethyl-1,10-phenanthroline, dicnq = 6,7-dicyanodipyridoquinoxaline) were characterized by IR and X-ray diffraction. Further fluorescence spectroscopy, photocatalytic properties and terahertz time-domain spectra (THz-TDS) were performed on 2 – 6. Complexes 1 – 3 and 6 were binuclear, while 4 was mononuclear. Complex 5 was a coordination polymer, displaying a one-dimensional infinite chain. Moreover, complexes 1 , 2 and 4 were assembled via several pairs of C H⋯π interactions to 1D–3D supramolecular architectures. The emission peaks of the complexes 2 – 4 all exhibit a large degree of red shift, which may be tentatively attributed to the intraligand transition. Compounds 2 – 6 represented the first examples of Ag(I) complexes bearing both diphosphine and diimine ligands that exhibit high, efficient photocatalytic abilities for dye degradation under UV light and show good stability toward photocatalysis. [ABSTRACT FROM AUTHOR]

Abstract: 1,10-Phenanthroline (Phen) adducts [M(L)Phen] in copper(II), cobalt(II), and zinc(II) chelates based on N,N,O-tridentate tosylamino-functionalized pyrazole-containing Schiff base (H2L), resulting from condensation of 2-tosylaminoaniline with 3-methyl-1-phenyl-4-formylpyrazol-5-ol, were obtained by electrosynthesis. The composition and structure of the mixed-ligand complexes were confirmed by elemental analysis, IR spectroscopy, and magnetochemical measurements. The structures of azomethine H2L and mixed-ligand copper(II) complex were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

There is an urgent need to discover new, selective compounds to add to the limited arsenal of chemotherapeutics displaying selective toxicity for aggressive triple-negative breast cancer (TNBC) cells. The effect of two, recently developed metal-based half-sandwich complexes [Os(η6-pcym)(bphen)(dca)]PF6 (Os-dca) and [Ru(η6-pcym)(bphen)(dca)]PF6 (Ru-dca) [pcym = 1-methyl-4-(propan-2-yl)benzene (p-cymene); bphen = 4,7-diphenyl-1,10-phenanthroline (bathophenanthroline); dca = dichloroacetate] on triple-negative breast cancer cells MDA-MB-231 is reported. The complexes display selective toxicity in several tumor cells (at submicromolar concentrations), and a prominent effect is observed against highly progressive triple negative breast cancer MDA-MB-231 cells for Os-dca. The lower potency of Ru-dca in comparison with Os-dca is apparently connected with a relatively quick release of the dca ligand due to the hydrolysis of Ru-dca before this complex enters the cells. Remarkably, both Os-dca and Ru-dca reduce successfully metastasis-related properties of the triple-negative breast cancer cells such as migration, invasion, and re-adhesion. The anti-metastatic effects of Os-dca and Ru-dca are associated with their ability to suppress matrix metalloproteinase activity and/or production and reduce the expression of aquaporins. Further detailed mechanistic studies reveal that Os-dca reverses Warburg's effect and oncosis seems to be a prominent mode of cell death that predominates over apoptosis. As such, Os-dca can efficiently overcome the resistance of cancer cells to clinically-used apoptotic inducers cisplatin and carboplatin. The cytostatic and anti-metastatic properties of Os-dca in MDA-MB-231 provide a strong impetus for the development of new metal-based compounds to target hardly treatable human TNBC cells and displaying different modes of action compared to the antitumor metallodrugs in clinical use. [ABSTRACT FROM AUTHOR]

Due to the limited molecular design strategy, the development of ultrahigh color purity deep blue aggregation-induced emission (AIE) emitters with excellent photophysical and electroluminescence performances is still facing challenges at present. In this study, an effective design strategy for deep blue emitters is proposed, which can improve the performances of non-doped organic light-emitting diodes (OLEDs) by adjusting the link mode of the phenyl bridge and utilizing the steric hindrance effect of the rigid plane. Two new emitters, 3BCzPT and 4BCzPT, were obtained with phenanthroline acceptor and carbazole donor for deep blue emitting OLEDs. Particularly, 3BCzPT has been proven to have AIE characteristics through photophysical properties. Non-doped OLEDs with 3BCzPT demonstrate prominent electroluminescence (EL) performances reaching a maximum current efficiency (CEmax) of 6.3 cd A−1 and maximum external quantum efficiency (EQEmax) of 3.81%, well as ultrahigh color purity with Commission Internationale de L'Eclairage (CIE) coordinates of (0.151, 0.053). While the parameters of non-doped OLED based 4BCzPT are 4.2 cd A−1, 1.96% and (0.147, 0.082). Both emitters exhibit narrow EL spectra with the full-width at half maximum (FWHM) of 56 and 52 nm. • A strategy to construct deep blue AIE emitters with D-π-A-π-D configuration was proposed. • Highly twisted configurations are beneficial to the formation of weak intra/intermolecular interaction. • Non-doped OLEDs provided ultrapure deep blue emission with CIE x ≤0.15 and CIE y ≤0.08. • This feasible strategy can enrich the design strategy of deep blue emitters and further extend their application in OLEDs. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of the platinum(II) complexes, [Pt(AIP)(bpy)](PF6)2 (1) and [Pt(PIP)(phen)](PF6)2 (2), of anthracene- and pyrene-conjugated imidazophenanthroline ligands and their in vitro cytotoxicity toward the fibroblast cells and the HeLa cell lines are reported. MTT assay demonstrates their cytotoxicity against the HeLa cell lines with the IC50 values of 1.35 and 1.56 µM, respectively, and the cytotoxicity profiles indicate that the HeLa cell lines show more activity than the fibroblast cells. Trypan blue assay highlights significant damage on the HeLa cell lines with a pronounced reduction on their clonogenicity. AO/EB staining shows marked morphologic signs of apoptosis in a dose-dependent manner and the LDH and DNA laddering assays also lend support to the cytotoxicity of the complexes. The molecular docking study reveals that the complexes interact with DNA through hydrogen bonding. The TD-DFT energy-optimized structures of the complexes show that the platinum(II) center has a slightly distorted square-planar geometry. The TD-DFT modelled LUMOs receive major contributions from the platinum d-orbitals, while the HOMOs are delocalized largely on the anthracenyl- and pyrenyl ligands, resulting in the LMCT transition at 352 nm. The structural, bonding, electronic, and optical properties of the complexes 1 and 2 reported in the present work and that of [Pt(AIP)(phen)](PF6)2 (3) and [Pt(PIP)(bpy)](PF6)2 (4), reported by us recently, and the approved drugs cisplatin, carboplatin, and oxaliplatin are described in the light of the optimized geometries, ΔEHOMO-LUMO, polarizability (α), hyperpolarizability (β), Mulliken negativities, and dipole moments computed from the ab initio and DFT computational studies.Graphical abstract: The synthesis of Pt(II) complexes of anthracene- and pyrene-appended imidazophenanthroline ligands and their in vitro cytotoxicity against fibroblast cells and HeLa cell lines are reported. The DFT computational study of the complexes and cisplatin, carboplatin, and oxaliplatin are described in search of the ligand design features for the development of new Pt-drugs. [ABSTRACT FROM AUTHOR]

Two new 4-nitro-1,2-benzenedicarboxylate-bridged Cd(II) coordination polymers Cd(phen)(NPTA) 1 and Cd(im)2(NPTA)·H2O 2 (H2NPTA = 4-nitro-1,2-benzenedicarboxylic acid, phen = 1,10-phenanthroline, im = iminazole) are synthesized. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) computations are carried out to study the vibrational frequencies and electronic properties. The results are in compliance with the experimentally obtained structural and spectral data. [ABSTRACT FROM AUTHOR]

Three cyclometalated platinum(II) complexes with substituted imidazolyl phenanthrolines L1 – L3 have been synthesized and characterized using spectral and electrochemical techniques. The effect of substituent (in the appended aromatic ring to the imidazolyl moiety) on the electronic feature and redox potential of the cyclometalated platinum(II) complexes of general formula [Pt(ppy)(L1-L3)]Cl ( 1–3 ) are discussed. Complexes 1 – 3 are luminescent in the solution and solid state. Complex 1, with two trifluoromethyl moieties present in the ligand shows a higher degree of Pt II ⋯Pt II interaction than the ligand incorporated with N,N -dimethyl moiety. The excimer formation through π − π and d − π (Pt⋯Pt) interactions is evident and the degree of excimer formation is in the order 1 >2 > 3. Excited-state properties are corroborated by static and time-dependent density-functional theory. [ABSTRACT FROM AUTHOR]

The complexation of copper and 1,10-phenanthroline ( phen ) in the presence of the [B 12 H 12 ] 2− anion is studied in organic solvents. The starting reagents contain copper(I) salts. The reactions are carried out in air and accompanied with oxidation of copper(I). Varying solvents and starting reagents, we succeeded in synthesizing selectively copper(I), copper(II), and heterovalent copper(I,II) complexes. Mononuclear, tetranuclear, and polymeric copper(II) complexes as well as a mononuclear copper(I) complex and a mixed cationic mononuclear copper(I)/copper(II) complexes are isolated and characterized by IR-spectroscopy and X-ray diffraction. The electronic structure of mononuclear copper(II) complex [Cu II ( phen ) 2 Cl] 2 [B 12 H 12 ] 2CH 2 I 2 is studied by EPR. [ABSTRACT FROM AUTHOR]

A series of new 2,9‐bis[(substituted‐aminomethyl)phenyl]‐1,10‐phenanthroline derivatives was synthesized, and the compounds were screened in vitro against three protozoan parasites (Plasmodium falciparum, Leishmania donovani, and Trypanosoma brucei brucei). Biological results showed antiparasitic activity with IC50 values in the μ m range. The in vitro cytotoxicity of these molecules was assessed by incubation with human HepG2 cells; for some derivatives, cytotoxicity was observed at significantly higher concentrations than antiparasitic activity. The 2,9‐bis[(substituted‐aminomethyl)phenyl]‐1,10‐phenanthroline 1h was identified as the most potent antimalarial candidate with ratios of cytotoxic‐to‐antiparasitic activities of 107 and 39 against a chloroquine‐sensitive and a chloroquine‐resistant strain of P. falciparum, respectively. As the telomeres of the parasite P. falciparum are the likely target of this compound, we investigated stabilization of the Plasmodium telomeric G‐quadruplexes by our phenanthroline derivatives through a FRET melting assay. The ligands 1f and 1m were noticed to be more specific for FPf8T with higher stabilization for FPf8T than for the human F21T sequence. [ABSTRACT FROM AUTHOR]

The different anticancer activities of two Cu (II) -complexes are reported: 1) containing acetylacetonate (acac), NO 3 − and 2,9-dimethyl-1,10-phenanthroline (2,9-dmp), 2) containing acetylacetonate (acac), NO 3 − and 1,10-phenanthroline (phen). Cytotoxicity test shown that complex 1 has much higher inhibition rate than complex 2 especially, higher than the famous anticancer drug 5-Fu. In this paper, we associated the bond length of complexes with their anticancer activity, and demonstrated that (1) in water solution the bonds of L-Cu II (2,9-dmp) will neither stay coordinated nor break up completely, but change into a transition state with weaker linkage than those in a solid state; (2) the superior anticancer activates of complex 1 correspond to the increased flexibility between ligand and Cu II as the bond length was elongated in solution; (3) The high energy transition State of complex 1 in water solution is more effective in oxidizing O 2 − into O 2 than complex 2 . [ABSTRACT FROM AUTHOR]

Abstract: Two phenanthroline‐derived Schiff base‐like ligands with a covalently linked ruthenium(II) phosphorescent unit were synthesised and converted into bimetallic RuII–NiII complexes. The optical properties were studied to examine a possible photoluminescence quenching through a nonradiative energy‐transfer upon a coordination‐induced spin‐state switch (CISSS) at the nickel(II) centre. Therefore, the metalloligands and the nickel(II) complexes were studied using UV/Vis absorbance, steady‐state, and time‐resolved emission spectroscopy in solutions of MeCN and pyridine. It is demonstrated that the nature of the bridging ligand between the ruthenium(II) donor and the nickel(II) acceptor strongly influences the photophysical behaviour upon CISSS. For the complex with a phenazine bridge, photoluminescence quenching is observed in the presence of a paramagnetic nickel(II) centre. [ABSTRACT FROM AUTHOR]

Three isomeric phenanthroline compounds, namely 2-DP, 3-DP and 5-DP, are constructed by incorporating 4-(2,2-diphenyl-vinyl)-phenyl unit into 2-, 3-, and 5-positions of phenanthroline. This approach functionalizes these compounds to exhibit different solvatochromism effects and metal-ion sensing abilities. 2-DP shows no obvious sensitivity for proton solvent and metal ions, but it's quite the opposite for 3-DP and 5-DP. Significantly, 3-DP possesses higher selectivity and sensitivity to Zn 2+ than 5-DP to Zn 2+ , with a limit of detection down to 10 −8  M. The density function theory calculations reveal that their different sensing behaviors are related to their steric hindrance and electronic effects. Moreover, 2-DP, 3-DP and 5-DP all exhibit aggregation-induced enhanced emission (AIEE), in which the photoluminescence (PL) enhancement of 2-DP is the biggest in aggregated state. It is thought that the molecule torsion degree is responsible for their different AIEE behaviors, which is supported by the X-ray structural analysis. The isomer engineering for phenanthroline provides a simple method to enhance the selectivity and sensitivity to metal ions, and to optimize solid-state luminescence properties. [ABSTRACT FROM AUTHOR]

The atomic structure of crystals of the complex Tb(AcAc) 3 Phen (AA –acetylacetonate-anion, Phen – 1,10 - phenanthroline) characterized by an intensive luminescence and triboluminescence has been determined by means of the X-ray structural analysis method. The crystal structure is represented by individual С 27 Н 29 N 2 O 6 Tb complexes linked through van der Waals interactions with clearly expressed cleavage planes. The structural aspects of the suggested model of formation of the triboluminescent properties have been considered and the role of the cleavage planes has been discussed. The notions of destruction zone and destruction zone width were introduced for the crystal under mechanical impact. This zone boundaries and width are naturally determined by surfaces spreading through central Tb atoms of molecular complexes, on which the ionization of charged acetylacetonate ions occurs as a result of the mechanical impact. In the case of the studied complex, the width of such destruction zone is equal to 6.414 Å. [ABSTRACT FROM AUTHOR]

A potentiometric perchlorate-selective electrode based on a phenanthroline derivative, neocuproine (2,9-dimethyl-1,10-phenanthroline), was developed. An electroactive substance, a neocuproine complex of Cu2+, providing a selective response to perchlorate was formed in situ in the electrode membrane structure during the conditioning process. Membrane optimization studies showed that the most suitable membrane composition was 1.0% (w/w) neocuproine, 69.0% (w/w) o-nitrophenyloctylether (o-NPOE) and 30.0% (w/w) poly(vinyl chloride) (PVC) in terms of potentiometric performance characteristics. For the proposed electrode, the linear range, slope, detection limit, pH working range and response time were determined as 2.5 × 10-7-1.0 × 10-1 M, -53.01 mV/decade, 1.0 × 10-7 M, 4.0-12.5 and ≈3 s, respectively. The proposed sensor was successfully used in the determination of perchlorate contents of some perchlorate spiked tap, river and dam water samples. [ABSTRACT FROM AUTHOR]

Two Europium(III) complexes [Eu(NCP)(1,4-bdc)] n ·0.5H 2 O ( 1 ) and [Eu(NCP)(4,4′-bpdc)] n ·0.75H 2 O ( 2 ) (HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline, 1,4-H 2 bdc = benzene-1,4-dicarboxylic acid, 4,4′-H 2 bpdc = 4,4′-biphenyldicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single crystal X-ray diffraction. Structural analyses revealed that two complexes all exhibit three-dimensional network structures with a Schläfli symbol of 4 12 ·6 3 topologies. In addition, these two metal-organic frameworks present excellent thermal stabilities and the preferential adsorption of CO 2 over N 2 . [ABSTRACT FROM AUTHOR]

A series of lanthanide pimelates [Sm(phen)(Hpim)(pim)] n ·1.5nH 2 O ( 1 , phen = 1,10-phenanthroline, H 2 pim = pimelic acid), and [ Ln (phen)(pim)] n ·nClO 4 ·nH 2 O [ Ln  = Gd ( 2a ), Tb ( 2b ), Er ( 2c )] have been hydrothermally synthesized and characterized structurally by elemental analysis, IR spectroscopy, thermogravimetric analysis and PXRD. Compound 1 contains 1-D neutral [Sm(phen)(Hpim)(pim)] n chain that is constructed by the linkages of [Sm(phen)] ions and pim 2− /Hpim − ligands, while compounds 2a - c contain 1-D cationic [ Ln (phen)(pim) + ] n chain with ClO 4− ion as counterion. Although a lot of lanthanide coordination polymers were obtained with aliphatic dicarboxylic acids, they usually show neutral frameworks. Compounds 2a - c provide the only examples of cationic lanthanide pimelate frameworks decorated by phen chromophores. The photoluminescent properties of 1 and 2b - c , and magnetic properties of all compounds have been studied. [ABSTRACT FROM AUTHOR]

Addition of 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen) or 2-aminopyridine (2-NH2-py) to aqueous solutions of (NH4)[NbO(C2O4)2(H2O)2]·3H2O (Nb-Ox) yields tris-oxalate complexes (bpyH2)(bpyH)[NbO(C2O4)3]·2H2O (1), (phenH)3[NbO(C2O4)3]·3H2O (2), and (2-NH2-pyH)3[NbO(C2O4)3]·2H2O (3), which were characterised by XRD, IR and EA. Bipyridinium salt 1 demonstrates remarkable photoactivity even under irradiation by daylight. The nature of the photoactivity was studied by diffuse reflectance (DR) spectroscopy, ESR and quantum-chemical calculations. [ABSTRACT FROM AUTHOR]

A series of copper(I) pseudorotaxanes has been prepared from bis[2-(diphenylphosphino)phenyl] ether (POP) and macrocyclic phenanthroline ligands with different ring sizes (m30, m37, and m42). Variabletemperature studies carried out on the resulting [Cu(mXX)(POP)]+ (mXX = m30, m37, and m42) derivatives have revealed a dynamic conformational equilibrium due to the folding of the macrocyclic ligand. The absorption and luminescence properties of the pseudorotaxanes have been investigated in CH2Cl2. They exhibit metal-to-ligand charge-transfer emission with photoluminescence quantum yields (PLQYs) in the range 20-30%. The smallest system [Cu(m30)(POP)]+ shows minimal differences in spectral shape and position compared to its analogues, suggesting a slightly distorted coordination environment. PLQY is substantially enhanced in poly(methyl methacrylate) films (~40-45%). The study of emission spectra and excitedstate lifetimes in powder samples as a function of temperature (78-338 K) reveals thermally activated delayed fluorescence, with sizable differences in the singlet-triplet energy gap compared to the reference compound [Cu(dmp)(POP)][sup +] (dmp = 2,9-dimethyl-1,10-phenanthroline) and within the pseudorotaxane series. The system with the largest ring ([Cu(m42)(POP)]+) has been tested as emissive material in OLEDs and affords bright green devices with higher luminance and greater stability compared to [Cu(dmp)(POP)]+, which lacks the macrocyclic ring. This highlights the importance of structural factors in the stability of electroluminescent devices based on Cu(I) materials. [ABSTRACT FROM AUTHOR]

The sensing ability of 2-(anthracen-9-yl) -1H-imidazo [4, 5-f] [1, 10] phenanthroline ( 1 ) has been exhaustively investigated towards cations and anions using UV–vis and fluorescence spectroscopy in CH 3 CN. 1,10-phenanthroline played a major role in both cation and anion recognition as 1 exhibited little and medium selectivity towards cations and anions respectively. 1 exhibited fluorescence quenching with all the tested transition metal ions of first transition series, based on photoinduced electron transfer. The basic anions (CN - , F - and AcO - ) exhibited new absorption bands and quenching of fluorescence emission intensity with 1 indicating deprotonation of imidazole NH (pK a = 11.05). To establish the undesirable role of 1, 10-phenanthroline and to improvise upon the selectivity, a model chemosensor 2 was synthesized containing benzil instead of phenanthroline. Both, the non availability of phenanthroline N's and decreased acidity of imidazole NH in 2 (pK a = 11.96) were expected to enhance selectivity of 2 for cations and anions respectively. Interestingly, the results of detailed photophysical examination of 2 in CH 3 CN revealed 2, a better and selective chemosensor for cations and anions than 1 . Moreover , 2 manifested colorimetric sensing response, exclusively for Cu 2+ ions by a distinct color change from colorless to greenish yellow. [ABSTRACT FROM AUTHOR]

The extraction and separation of uranium (U(VI)) and thorium (Th(IV)) from rare earth elements (REEs) in acidic waste solutions is very important and still challenging. In this paper, a high-efficient sorbent was successfully prepared by functionalization of graphene oxide with phenanthroline diamide (GO-PDA), which exhibited excellent selectivity towards actinides over lanthanides. The sorption behaviors of GO-PDA towards U(VI) and Th(IV) under various conditions were evaluated by batch experiment. Fast sorption kinetics and high sorption capacities were realized for both U(VI) and Th(IV), which reached equilibrium in 60 min. The sorption isotherms of both U(VI) and Th(IV) coincided with Langmuir model, while the maximum sorption capacities of U(VI) (pH = 5.5) and Th(IV) (pH = 4.0) at 298 K were calculated to be 718 and 703 mg/g respectively, which were much higher than most of the previously reported graphene oxide (GO) based sorbents. GO-PDA also possessed significantly enhanced selectivity for U(VI) and Th(IV) over Eu(III), Nd(III) and Sm(III) compared to pristine GO at ultralow low pH (0−2), with separation factors larger than 23 at pH 0. Most importantly, GO-PDA was made into membrane with porous structure, which achieved fast and efficient separation of U(VI) and Th(IV) from Eu(III), Nd(III) and Sm(III) in aqueous solution. This work demonstrates that GO-PDA is a promising sorbent for efficient selective separation of U(VI) and Th(IV) from REEs in strong acidic waste solutions, which is of great value for nuclear waste management and nuclear fuel recycling. [ABSTRACT FROM AUTHOR]

The Fe3O4 magnetic nano-particles were modified with 1,10-phenanthroline-5,6-diol and the relevant Mn complex (Fe@Phendiol@Mn) synthesized as a nano-magnetic heterogeneous catalyst to be used for the synthesis of various arylaminotetrazoles from various arylcyanamides and sodium azide in DMF at 120 °C. Also, the nano-catalyst characterized by different methods such as the elemental analysis (CHN), ICP, FT-IR, XRD, EDX, SEM, TEM, TG-DTA, VSM and XPS. In addition, the theoretical study of the Fe@Phendiol@Mn nano-catalyst was performed using the Gausian software. The calculated results showed that the Gibbs free energy and the standard enthalpy values are negative; therefore the complex is stable. Incidentally, the computational chemistry descriptions including the electronic chemical potential, global hardness, electrophilicity index, energy gap, global softness and electronegativity were calculated. [ABSTRACT FROM AUTHOR]

Two new nickel(II) and copper(II) complexes of2-(Furan-2-yl)-1H-Imidazo[4,5-f][1,10]Phenanthroline(FIP) and2-(thiophen-2-yl)-1H-imidazo[4,5-f][1,10]phenanthroline(TIP), imidazophen derivatives were synthesized. The structures of the compounds were determined by UV-visible and FT-IR spectroscopic methods and elemental analysis. The biological activities of Ni and Cu complexes, as anticancer agents, were tested against chronic myelogenous leukemia cell line, K562, at micromolar concentration. The MTT studies showed Cc50values are 21 and 160 µM for Cu and Ni(II) complexes, respectively; suggesting that Ni (II) complex has Cc50almost seven times of that obtained for cisplatin. Biological activity of the Ni(II) and Cu(II) complexes were also assayed against selective microorganisms by disc diffusion method. These results showed that the Cu(II) complex is antifungal agent but Ni(II) complex has antibacterial activity. [ABSTRACT FROM AUTHOR]