Log in

Relevant bibliographies by topics / Fluorine-substituted ligand / Journal articles

Journal articles on the topic 'Fluorine-substituted ligand'

To see the other types of publications on this topic, follow the link: Fluorine-substituted ligand.

Author: Grafiati

Published: 4 June 2021

Last updated: 3 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 41 journal articles for your research on the topic 'Fluorine-substituted ligand.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Reimer, Mark L. J., John B. Westmore, and Manoranjan Das. "Electron ionization mass spectrometry of cobalt(III) β-diketonates and monothio-β-diketonates possessing aryl and fluorinated alkyl substituents." Canadian Journal of Chemistry 70, no. 3 (March 1, 1992): 952–63. http://dx.doi.org/10.1139/v92-128.

Full text

Abstract:

Electron ionization positive ion mass spectra of 15 substituted cobalt(III) β-diketonates and monothio-β-diketonates, CoIIIL3, where L = RCXCHCOR′, R = phenyl, 2-thienyl, or 2-naphthyl; X = O or S; and R′ = CHF2, CF3, C2F5, or n-C3F7, show a marked dependence on the ligand. Molecular ions, [CoIIIL3]+•, are observed only for some of the more highly fluorinated complexes (R′ = C2F5 or n-C3F7). The [CoIIIL2]+• ion, possibly generated by ionization of CoIIL2 formed by thermal degradation, or by electron ionization of CoIIIL3, typically decomposes by elimination of a radical, i.e., L• or R′•, to yield ions containing Co(II); subsequent decompositions proceed preferentially by loss of even-electron neutral species, also to yield ions containing Co(II). Cobalt-containing ions in which fluorine has rearranged to the metal decrease in variety and abundance for the ligands with higher fluorine content. When metal-bonded oxygen is replaced by sulfur, fluorine migration to Co(III), rather than to Co(II), is preferred. These trends are consistent with a combination of several different concepts including the ability of the metal to undergo valency change, the principle of Hard and Soft Acids and Bases, and the inductive capabilities of the ligand donor atoms and of the R and R′ groups. Ion decomposition pathways are proposed. Keywords: mass spectrometry, cobalt complexes, β-diketonates, fluorinated chelate complexes.

APA, Harvard, Vancouver, ISO, and other styles

2

Kaczmarzyk, Tomasz, Katarzyna Dziedzic-Kocurek, Iwona Rutkowska, and Kazimierz Dziliński. "Mössbauer study of a tetrakis (pentafluorophenyl) porphyrin iron (III) chloride in comparison with the fluorine unsubstituted analogue." Nukleonika 60, no. 1 (March 1, 2015): 57–61. http://dx.doi.org/10.1515/nuka-2015-0013.

Full text

Abstract:

Abstract Mössbauer investigations, in association with density functional theory (DFT) calculations, have been conducted for the molecular and electronic structures of iron (III) [tetrakis (pentafluorophenyl)] porphyrin chloride [(F20TPP)Fe:Cl], as a Fe(III)-tetraphenylporphyrin complex containing chloride axial ligand and substituted hydrogen atoms by fluorine ones in the four phenyl rings, in comparison with its fluorine unsubstituted analogue [(TPP)Fe:Cl]. It was found that the parameters of Mössbauer spectra of both complexes are close to one another, and correspond to the high-spin state of Fe(III) ions, but they show the different temperature dependence and the quadrupole doublets in Mössbauer spectra show different asymmetry at low temperatures. Results of DFT calculations are analyzed in the light of catalytic activity of the halogenated complex.

APA, Harvard, Vancouver, ISO, and other styles

3

Spiridonova, Yulia S., Yulia A. Nikolaeva, Anna S. Balueva, Elvira I. Musina, Igor A. Litvinov, Igor D. Strelnik, Vera V. Khrizanforova, Yulia G. Budnikova, and Andrey A. Karasik. "Synthesis and Structure of Iron (II) Complexes of Functionalized 1,5-Diaza-3,7-Diphosphacyclooctanes." Molecules 25, no. 17 (August 19, 2020): 3775. http://dx.doi.org/10.3390/molecules25173775.

Full text

Abstract:

In order to synthesize new iron (II) complexes of 1,5-diaza-3,7-diphosphacyclooctanes with a wider variety of the substituents on ligands heteroatoms (including functionalized ones, namely, pyridyl groups) and co-ligands, it was found that these ligands with relatively small phenyl, benzyl, and pyridin-2-yl substituents on phosphorus atoms in acetonitrile formed bis-P,P-chelate cis-complexes [L2Fe(CH3CN)2]2+ (BF4)2−, whereas P-mesityl-substituted ligand formed only monoligand P,P-complex [LFe(CH3CN)4]2+ (BF4)2−. 3,7-dibenzyl-1,5-di(1′-(R)-phenylethyl)-1,5-diaza-3,7-diphosphacyclooctane reacted with hexahydrate of iron (II) tetrafluoroborate in acetone to give an unusual bis-ligand cationic complex of the composition [L2Fe(BF4)]+ BF4−, where two fluorine atoms of the tetrafluoroborate unit occupied two pseudo-equatorial positions at roughly octahedral iron ion, according to X-ray diffraction data. 1,5-diaza-3,7-diphosphacyclooctanes replaced tetrahydrofurane and one of the carbonyl ligands of cyclopentadienyldicarbonyl(tetrahydrofuran)iron (II) tetrafluoroborate to form heteroligand complexes [CpFeL(CO)]+BF4−. The structural studies in the solid phase and in solutions showed that diazadiphosphacyclooctane ligands of all complexes adopted chair-boat conformations so that their nitrogen atoms were in close proximity to the central iron ion. The redox properties of the obtained complexes were performed by the cyclic voltammetry method.

APA, Harvard, Vancouver, ISO, and other styles

4

Arrieta-Rodríguez, Loreto, Daniela Espinoza-Rosales, Gonzalo Vera, Young Hwa Cho, David Cabezas, David Vásquez-Velásquez, Jaime Mella-Raipán, Carlos F. Lagos, and Gonzalo Recabarren-Gajardo. "Novel N-Arylsulfonylindoles Targeted as Ligands of the 5-HT6 Receptor. Insights on the Influence of C-5 Substitution on Ligand Affinity." Pharmaceuticals 14, no. 6 (June 1, 2021): 528. http://dx.doi.org/10.3390/ph14060528.

Full text

Abstract:

A new series of twenty-two C-5 substituted N-arylsulfonylindoles was prepared with the aim of exploring the influence of C-5 substitution on 5-HT6 receptor affinity. Eleven compounds showed moderate to high affinity at the receptor (Ki = 58–403 nM), with compound 4d being identified as the most potent ligand. However, regarding C-5 substitution, both methoxy and fluorine were detrimental for receptor affinity compared to our previously published unsubstituted compounds. In order to shed light on these observations, we performed docking and molecular dynamics simulations with the most potent compounds of each series (4d and 4l) and PUC-10, a highly active ligand previously reported by our group. The comparison brings about deeper insight about the influence of the C-5 substitution on the binding mode of the ligands, suggesting that these replacements are detrimental to the affinity due to precluding a ligand from reaching deeper inside the binding site. Additionally, CoMFA/CoMSIA studies were performed to systematize the information of the main structural and physicochemical characteristics of the ligands, which are responsible for their biological activity. The CoMFA and CoMSIA models presented high values of q2 (0.653; 0.692) and r2 (0.879; 0.970), respectively. Although the biological activity of the ligands can be explained in terms of the steric and electronic properties, it depends mainly on the electronic nature.

APA, Harvard, Vancouver, ISO, and other styles

5

Kang, Hyun-Ju, Kum-Hee Lee, Suk-Jae Lee, Ji-Hyun Seo, Young-Kwan Kim, and Seung-Soo Yoon. "Highly Efficient Red Phosphorescent OLEDs Based on Ir(III) Complexes with Fluorine-substituted Benzoylphenylpyridine Ligand." Bulletin of the Korean Chemical Society 31, no. 12 (December 20, 2010): 3711–17. http://dx.doi.org/10.5012/bkcs.2010.31.12.3711.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Raven, William, Thomas Joschko, Irmgard Kalf, and Ulli Englert. "Hydrogenversusfluorine: effects on molecular structure and intermolecular interactions in a platinum isocyanate complex." Acta Crystallographica Section C Structural Chemistry 72, no. 3 (February 13, 2016): 184–88. http://dx.doi.org/10.1107/s2053229616002382.

Full text

Abstract:

At the molecular level, the enantiomerically pure square-planar organoplatinum complex (SP-4-4)-(R)-[2-(1-aminoethyl)-5-fluorophenyl-κ2C1,N][(R)-1-(4-fluorophenyl)ethylamine-κN](isocyanato-κN)platinum(II), [Pt(C8H9FN)(NCO)(C8H10FN)], and its congener without fluorine substituents on the aryl rings adopt the same structure within error. The similarities between the compounds extend to the most relevant intermolecular interactions,i.e.N—H...O and N—H...N hydrogen bonds link neighbouring molecules into chains along the shortest lattice parameter in each structure. Differences between the crystal structures of the fluoro-substituted and parent complex become obvious with respect to secondary interactions perpendicular to the classical hydrogen bonds; the fluorinated compound features short C—H...F contacts with an F...H distance ofca2.6 Å. The fluorine substitution is also reflected in reduced backbonding from the metal cation to the isocyanate ligand.

APA, Harvard, Vancouver, ISO, and other styles

7

Smirnov, Alexey, Asta Zubrienė, Elena Manakova, Saulius Gražulis, and Daumantas Matulis. "Crystal structure correlations with the intrinsic thermodynamics of human carbonic anhydrase inhibitor binding." PeerJ 6 (February 26, 2018): e4412. http://dx.doi.org/10.7717/peerj.4412.

Full text

Abstract:

The structure-thermodynamics correlation analysis was performed for a series of fluorine- and chlorine-substituted benzenesulfonamide inhibitors binding to several human carbonic anhydrase (CA) isoforms. The total of 24 crystal structures of 16 inhibitors bound to isoforms CA I, CA II, CA XII, and CA XIII provided the structural information of selective recognition between a compound and CA isoform. The binding thermodynamics of all structures was determined by the analysis of binding-linked protonation events, yielding the intrinsic parameters, i.e., the enthalpy, entropy, and Gibbs energy of binding. Inhibitor binding was compared within structurally similar pairs that differ bypara-ormeta-substituents enabling to obtain the contributing energies of ligand fragments. The pairs were divided into two groups. First,similarbinders—the pairs that keep the same orientation of the benzene ring exhibited classical hydrophobic effect, a less exothermic enthalpy and a more favorable entropy upon addition of the hydrophobic fragments. Second,dissimilarbinders—the pairs of binders that demonstrated altered positions of the benzene rings exhibited the non-classical hydrophobic effect, a more favorable enthalpy and variable entropy contribution. A deeper understanding of the energies contributing to the protein-ligand recognition should lead toward the eventual goal of rational drug design where chemical structures of ligands could be designed based on the target protein structure.

APA, Harvard, Vancouver, ISO, and other styles

8

Hori, Akiko, and Masaya Mizutani. "Synthesis and Crystal Structure Differences between Fully and Partially Fluorinated β-Diketonate Metal (Co2+, Ni2+, and Cu2+) Complexes." International Journal of Inorganic Chemistry 2011 (May 18, 2011): 1–8. http://dx.doi.org/10.1155/2011/291567.

Full text

Abstract:

Coordination complexes, [Co2(1)4(H2O)2] (2), [Ni2(1)4(H2O)2] (3), and [Cu(1)2] (4), by using an asymmetric and partially fluorinated 3-hydroxy-3-pentafluorophenyl-1-phenyl-2-propen-1-one (H1) have been prepared, and the structures were investigated to compare with the corresponding fully fluorinated complexes of [Co2(5)4(H2O)2] (6), [Ni2(5)4(H2O)2] (7), and [Cu(5)2] (8) with bis(pentafluorobenzoyl)methane (H5) and to understand the fluorine-substituted effects. While the coordination mode of the partially fluorinated complexes was quite similar to the fully fluorinated complexes, the intra- and intermolecular π-interactions of the ligand moieties were highly influenced by the fluorination effects; the arene-perfluoroarene interactions were observed in complexes 2 and 3 as a reason of the dinucleation. In this paper, we describe detail structures of the protonated form of the ligand, H1, and complexes 2–4 by X-ray crystallographic studies.

APA, Harvard, Vancouver, ISO, and other styles

9

Islam, Ashraful, Firoz A. Chowdhury, Yasuo Chiba, Ryoichi Komiya, Nobuhiro Fuke, Noriaki Ikeda, and Liyuan Han. "Ruthenium(II) Tricarboxyterpyridyl Complex with a Fluorine-substituted β-Diketonato Ligand for Highly Efficient Dye-sensitized Solar Cells." Chemistry Letters 34, no. 3 (March 2005): 344–45. http://dx.doi.org/10.1246/cl.2005.344.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Janjua, Muhammad Ramzan Saeed Ashraf, Zhong-Min Su, Wei Guan, Chun-Guang Liu, Li-Kai Yan, Ping Song, and Gull Maheen. "Tuning Second-Order Non-linear (NLO) Optical Response of Organoimido-Substituted Hexamolybdates through Halogens: Quantum Design of Novel Organic-Inorganic Hybrid NLO Materials." Australian Journal of Chemistry 63, no. 5 (2010): 836. http://dx.doi.org/10.1071/ch10094.

Full text

Abstract:

The second-order non-linear optical (NLO) response of organoimido-substituted hexamolybdates has been tuned from 218.61 × 10–30 to 490.10 × 10–30 esu. The dipole polarizabilities and second-order nonlinear optical (NLO) properties of organoimido derivatives of hexamolybdates have been investigated by using the time-dependent density functional response theory (TDDFT). The electron withdrawing ability of F (fluorine) has played an important role in tuning the second-order NLO response in this class of organic-inorganic hybrid compounds; particularly system 6 [Mo6O18(NC16H8F2(CF3)2I)]2– with the static second-order polarizability (βvec ) computed to be 490.10 × 10–30 esu. Thus, our studied systems have the feasibility to be excellent tuneable second-order NLO materials. The analysis of the major contributions to the βvec value suggests that the charge transfer (CT) from POM to organic ligand (D-A) along the z-axis has been enhanced with addition of F atoms at the end phenyl ring which directs head (POM) to tail (fluorinated ring) charge transfer. The computed βvec values have been tuned by incorporation of different halogen atoms at the end phenyl ring of organoimido segment. Furthermore, substitution of two trifluoromethyl (–CF3) groups sideways along with iodine (I) at the terminus of end phenyl ring in the organoimido ligand has a striking influence on tuning the optical non-linearity, as CT from POM to the organoimido ligand was significantly increased. These systematic small changes in molecular composition by substitution of different halogen groups leads to a tuning the NLO response; the so-called ‘ripple effect’ catches this point nicely. Thus, the present investigation provides thought provoking insight into the tuneable NLO properties of organoimido-substituted hexamolybdates.

APA, Harvard, Vancouver, ISO, and other styles

11

Ito, Yukishige, Shinya Hagihara, Midori A. Arai, Ichiro Matsuo, and Maki Takatani. "Synthesis of fluorine substituted oligosaccharide analogues of monoglucosylated glycan chain, a proposed ligand of lectin-chaperone calreticulin and calnexin." Glycoconjugate Journal 21, no. 5 (2004): 257–66. http://dx.doi.org/10.1023/b:glyc.0000045109.60425.2e.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Kurokawa, Hideki, Ryota Ogawa, Kazuhiro Yamamoto, Tsutomu Sakuragi, Masa-aki Ohshima, and Hiroshi Miura. "Nickel(II) Complex Bearing Fluorine-substituted α-Diimine Ligand Immobilized in Fluorotetrasilicic Mica Interlayer as Heterogeneous Catalysts for Ethylene Oligomerization." Journal of the Japan Petroleum Institute 57, no. 3 (2014): 146–54. http://dx.doi.org/10.1627/jpi.57.146.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Lee, Byung Chul, Kyo Chul Lee, Hsiaoju Lee, Robert H. Mach, and John A. Katzenellenbogen. "Synthesis and Binding Affinity of a Fluorine-Substituted Peroxisome Proliferator-Activated Gamma (PPARγ) Ligand as a Potential Positron Emission Tomography (PET) Imaging Agent." Bioconjugate Chemistry 18, no. 2 (March 2007): 507–13. http://dx.doi.org/10.1021/bc060190o.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Ziemniak, Marcin, Anna Zawadzka-Kazimierczuk, Sylwia Pawlędzio, Maura Malinska, Maja Sołtyka, Damian Trzybiński, Wiktor Koźmiński, et al. "Experimental and Computational Studies on Structure and Energetic Properties of Halogen Derivatives of 2-Deoxy-D-Glucose." International Journal of Molecular Sciences 22, no. 7 (April 2, 2021): 3720. http://dx.doi.org/10.3390/ijms22073720.

Full text

Abstract:

The results of structural studies on a series of halogen-substituted derivatives of 2-deoxy-D-glucose (2-DG) are reported. 2-DG is an inhibitor of glycolysis, a metabolic pathway crucial for cancer cell proliferation and viral replication in host cells, and interferes with D-glucose and D-mannose metabolism. Thus, 2-DG and its derivatives are considered as potential anticancer and antiviral drugs. X-ray crystallography shows that a halogen atom present at the C2 position in the pyranose ring does not significantly affect its conformation. However, it has a noticeable effect on the crystal structure. Fluorine derivatives exist as a dense 3D framework isostructural with the parent compound, while Cl- and I-derivatives form layered structures. Analysis of the Hirshfeld surface shows formation of hydrogen bonds involving the halogen, yet no indication for the existence of halogen bonds. Density functional theory (DFT) periodic calculations of cohesive and interaction energies (at the B3LYP level of theory) have supported these findings. NMR studies in the solution show that most of the compounds do not display significant differences in their anomeric equilibria, and that pyranose ring puckering is similar to the crystalline state. For 2-deoxy-2-fluoro-D-glucose (2-FG), electrostatic interaction energies between the ligand and protein for several existing structures of pyranose 2-oxidase were also computed. These interactions mostly involve acidic residues of the protein; single amino-acid substitutions have only a minor impact on binding. These studies provide a better understanding of the structural chemistry of halogen-substituted carbohydrates as well as their intermolecular interactions with proteins determining their distinct biological activity.

APA, Harvard, Vancouver, ISO, and other styles

15

Reimer, Mark L. J., John B. Westmore, and Manoranjan Das. "Electron ionization mass spectrometry of aryl- and fluoroalkyl-substituted nickel(II) β-diketonates and monothio-β-diketonates." Canadian Journal of Chemistry 71, no. 9 (September 1, 1993): 1450–62. http://dx.doi.org/10.1139/v93-187.

Full text

Abstract:

Electron ionization positive-ion mass spectra are reported for 18 substituted nickel(II) β-diketonates and monothio-β-diketonates, NiII(RCXCHCOR′)2, where X = O or S; R = phenyl, 2-thienyl, 5-methyl-2-thienyl, or 2-naphthyl; and R′ = difluoromethyl, trifluoromethyl, pentafluoroethyl, or n-heptafluoropropyl. Each mass spectrum contains a prominent molecular ion, [NiL2]+, which, for β-diketonates, fragments mainly by elimination of the odd-electron R′• species; the resulting ion decomposes by losses of one or more even-electron neutral species to yield ions containing nickel(II). In contrast, the major fragmentation of the molecular ion of monothio-β-diketonates is loss of NiIL to yield an abundant L+ ion. Furthermore, while most ions contain nickel(II), some prominent ions contain nickel(I); among these are [NiISC(R) = CH]+ and [NiI(HCCR)]+. Interesting ions are formed by hydrogen transfer processes. The [NiHL]+ ion is favored in the spectra of β-diketonates having a phenyl substituent, consistent with hydrogen transfer to the metal from the aryl group. On the other hand, the [Ni(L–H)]+ ion, favored for the monothio-β-diketonates, could be formed by hydrogen transfer from the central position of the chelate ring or from an aryl substituent. Alternative mechanisms of formation are discussed. Some minor ions are formed by fluorine transfer to nickel. The trends in their abundances are influenced by the hardness of nickel as an acid in its different oxidation states, under the influence of the ligand donor atoms, and by the hardness of the carbon atoms of the perfluoroalkyl substituents.

APA, Harvard, Vancouver, ISO, and other styles

16

Kosaka, Wataru, Masahisa Itoh, and Hitoshi Miyasaka. "The effect of chlorine and fluorine substitutions on tuning the ionization potential of benzoate-bridged paddlewheel diruthenium(ii, ii) complexes." Dalton Transactions 44, no. 17 (2015): 8156–68. http://dx.doi.org/10.1039/c5dt00505a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Ertl, Cathrin D., Jesús Cerdá, José M. Junquera-Hernández, Antonio Pertegás, Henk J. Bolink, Edwin C. Constable, Markus Neuburger, Enrique Ortí, and Catherine E. Housecroft. "Colour tuning by the ring roundabout: [Ir(C^N)2(N^N)]+ emitters with sulfonyl-substituted cyclometallating ligands." RSC Advances 5, no. 53 (2015): 42815–27. http://dx.doi.org/10.1039/c5ra07940c.

Full text

Abstract:

A series of fluorine-free blue and green emitting iridium complexes containing sulfone-substituted cyclometallating and pyrazolyl-pyridine ancillary ligands has been synthesized and their properties investigated.

APA, Harvard, Vancouver, ISO, and other styles

18

Khavasi, Hamid Reza, and Narjes Rahimi. "Fluorine-Substituted Ligands Induce Structural Diversity of Coordination Compounds." ChemistrySelect 2, no. 34 (December 1, 2017): 11314–21. http://dx.doi.org/10.1002/slct.201702047.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

DelaRosa, Mark J., Kulbinder K. Banger, Seiichiro Higashiya, Silvana C. Ngo, Daniel H. Hunt, Kenneth S. Bousman, Paul J. Toscano, and John T. Welch. "Structural investigations of copper(II) complexes containing fluorine-substituted β-diketonate ligands." Journal of Fluorine Chemistry 123, no. 1 (September 2003): 109–17. http://dx.doi.org/10.1016/s0022-1139(03)00141-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Li, Xin, Boris Minaev, Hans Ågren, and He Tian. "Theoretical Study of Phosphorescence of Iridium Complexes with Fluorine-Substituted Phenylpyridine Ligands." European Journal of Inorganic Chemistry 2011, no. 16 (April 18, 2011): 2517–24. http://dx.doi.org/10.1002/ejic.201100084.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Hu, Jiawei, Guanghui Zhang, Hung-Hsin Shih, Peipei Sun, and Chien-Hong Cheng. "Synthesis and luminescent properties of Ir complexes with fluorine substituted phenylpyridine derivative ligands." Synthetic Metals 158, no. 21-24 (December 2008): 912–16. http://dx.doi.org/10.1016/j.synthmet.2008.06.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Feng, Xun, Yapei Shang, Heng Zhang, Rongfang Li, Weizhou Wang, Daoming Zhang, Liya Wang, and Zhongjun Li. "Enhanced luminescence and tunable magnetic properties of lanthanide coordination polymers based on fluorine substitution and phenanthroline ligand." RSC Advances 9, no. 29 (2019): 16328–38. http://dx.doi.org/10.1039/c9ra01574d.

Full text

Abstract:

Lanthanide coordination polymers with F-substituted carboxylate tectonics and phenanthroline ligands exhibit emission from the visible to near-infrared region with long lifetime. Dy(iii) compounds show temperature dependent and field induced single molecule magnetism.

APA, Harvard, Vancouver, ISO, and other styles

23

Kim, Jwajin, Kum Hee Lee, Seok Jae Lee, Ho Won Lee, Young Kwan Kim, Young Sik Kim, and Seung Soo Yoon. "Red Phosphorescent Bis-Cyclometalated Iridium Complexes with Fluorine-, Phenyl-, and Fluorophenyl-Substituted 2-Arylquinoline Ligands." Chemistry - A European Journal 22, no. 12 (February 16, 2016): 4036–45. http://dx.doi.org/10.1002/chem.201504392.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Kim, Sung-Hoon, Stephanie D. Jonson, Michael J. Welch, and John A. Katzenellenbogen. "Fluorine-Substituted Ligands for the Peroxisome Proliferator-Activated Receptor Gamma (PPARγ): Potential Imaging Agents for Metastatic Tumors." Bioconjugate Chemistry 12, no. 3 (May 2001): 439–50. http://dx.doi.org/10.1021/bc000153b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Feng, Xun, Yi-Ling Sun, Rong-Fang Li, Tian Zhang, Nan Guo, and Li-Ya Wang. "Two novel europium coordination polymers based on fluorine substituted and similar carboxylate ligands: Syntheses, structures and luminescence." Inorganic Chemistry Communications 73 (November 2016): 190–95. http://dx.doi.org/10.1016/j.inoche.2016.10.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Kim, S. H., S. D. Jonson, M. J. Welch, and J. A. Katzenellenbogen. "Fluorine-substituted ligands for the peroxisome proliferator-activated receptor gamma (Pparγ): Potential imaging agents for metastatic tumors." Journal of Labelled Compounds and Radiopharmaceuticals 44, S1 (May 2001): S316—S318. http://dx.doi.org/10.1002/jlcr.25804401111.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Lengkeek, Nigel A., Maxine P. Roberts, Lei Zhang, I.-Chieh J. Lee, Christopher J. R. Fookes, Branko Dikic, Herbert Herzog, Andrew Katsifis, and Ivan Greguric. "Synthesis and Binding Affinity of Fluorine Containing NG-acyl and -sulfonyl BIBP3226 Derivatives: Ligands for the NPY Y1 Receptor." Australian Journal of Chemistry 69, no. 7 (2016): 746. http://dx.doi.org/10.1071/ch15569.

Full text

Abstract:

The neuropeptide Y (NPY) receptors are abundant in a range of tumours hence are a molecular target for tumour imaging and therapy, particularly by the use of radiolabelled molecules. NG-Substituted derivatives of the NPY receptor antagonist, BIBP3226, were prepared aiming to improve its current usability and to incorporate a positron-emitting radioisotope for development in positron emission tomography (PET) radiopharmaceuticals. The BIBP3226 derivatives were prepared in seven steps while retaining the critically important amino acid chirality. The acyl derivative retained acceptable ligand binding, however the sulfonyl derivatives lost almost all binding affinity.

APA, Harvard, Vancouver, ISO, and other styles

28

Reimer, Mark L. J., John B. Westmore, and Manoranjan Das. "Electron ionization mass spectrometry of aryl- and fluoroalkyl-substituted palladium(II) β-diketonates and monothio-β-diketonates." Canadian Journal of Chemistry 72, no. 5 (May 1, 1994): 1302–11. http://dx.doi.org/10.1139/v94-163.

Full text

Abstract:

Positive ion electron ionization mass spectra are presented for palladium(II) β-diketonates and monothio-β-diketonates of the general form PdII[RC(X)CHC(O)R′]2, where R = phenyl, 4-methoxyphenyl, 2-thienyl, or 2-naphthyl; R′ = trifluoromethyl, pentafluoroethyl, or n-heptafluoropropyl; and X = O or S. The mass spectral behavior is in sharp contrast to that of metals of the first transition series. The spectra of the β-diketonates are dominated by metal-containing ions that arise by migration of the R group from the ligand (L) to palladium, but there is no evidence for fluorine-to-metal transfer. These findings are consistent with HSAB theory. The strong tendency of palladium to form bonds with unsaturated carbon also leads to remarkably abundant metal-containing ions that arise by losses of CO or aryloxy radicals from [PdRL]+• ions. In contrast, in decompositions of ions in the spectra of the monothio-β-diketonates, migration of the R group is suppressed; competition for palladium dπ electrons by the sulfur donor makes palladium a poorer aryl group acceptor.

APA, Harvard, Vancouver, ISO, and other styles

29

Strasser, Ulf H., Beate Neumann, Hans-Georg Stammler, Raphael J. F. Berger, and Norbert W. Mitzela. "Gilded Chalices: Tetra-aurated Calix[4]arenes." Zeitschrift für Naturforschung B 69, no. 11-12 (December 1, 2014): 1061–72. http://dx.doi.org/10.5560/znb.2014-4149.

Full text

Abstract:

Abstract 5,11,17,23-Tetrakis(trimethylsilylethynyl)-25,26,27,28-tetra-n-propoxycalix[4]arene (1) was synthesised in two steps starting from 25,26,27,28-tetra-n-propoxycalix[4]arene, and the structure of 1 was determined by X-ray diffraction. Compound 1 was desilylated (K2CO3) to give 5,11,17,23- tetrakis(ethynyl)-25,26,27,28-tetra-n-propoxycalix[4]arene (2), which was tetra-aurated under basic conditions (NaOEt, THF) with a series of phosphane-gold chlorides (o-Tol3PAuCl, Ph3PAuCl, Ph2MePAuCl, PhMe2PAuCl, Me3PAuCl, Cy3PAuCl, t-Bu3PAuCl) to afford in good to excellent yields the tetra-aurated tetraethynylcalix[4]arene species 3-9 in one step [with phosphane ligands o-Tol3P (3), Ph3P (4), Ph2MeP (5), PhMe2P (6), Me3P (7), Cy3P (8), t-Bu3P (9)]. All compounds were characterised by 1H NMR and infrared spectroscopy, mass spectrometry and by elemental analyses, additionally 3, 4, 5, 8 and 9 by 13C{1H}, and 3-6, 8 and 9 by 31P{1H} NMR spectroscopy. The molecular structures of complexes 3 and 9 were determined by X-ray diffraction and show pinched-cone conformations, but neither intra- nor intermolecular attractive aurophilic Au···Au contacts. The acceptor ability of complexes 3 and 9 was investigated by complexation attempts with various phosphane-gold chlorides and xenon gas under pressure, but interactions could not be determined experimentally. The formation of a complex between xenon and gilded calix[4]arene could, however, be predicted for fluorine-substituted species and with very small phosphane ligands (PH3) on the basis of quantum-chemical calculations; the energy of formation is 9:6 kJ mol-1. The crystal structure of Ph2MePAuCl was also determined and shows Au···Au-bonded dimers.

APA, Harvard, Vancouver, ISO, and other styles

30

Sasaki, Shigeki, Nobuyasu Ishibashi, Tshuneo Kuwamura, Hiromi Sano, Masaki Matoba, Tohru Nisikawa, and Minoru Maeda. "Excellent acceleration of the Diels-Alder reaction by microwave irradiation for the synthesis of new fluorine-substituted ligands of NMDA receptor." Bioorganic & Medicinal Chemistry Letters 8, no. 21 (November 1998): 2983–86. http://dx.doi.org/10.1016/s0960-894x(98)00541-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Liu, Aijun, Kathryn E. Carlson, and John A. Katzenellenbogen. "Synthesis of high-affinity fluorine-substituted ligands for the androgen receptor. Potential agents for imaging prostatic cancer by positron emission tomography." Journal of Medicinal Chemistry 35, no. 11 (May 1992): 2113–29. http://dx.doi.org/10.1021/jm00089a024.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Van Den Bossche, Bieke, and Christophe Van de Wiele. "Receptor Imaging in Oncology by Means of Nuclear Medicine: Current Status." Journal of Clinical Oncology 22, no. 17 (September 1, 2004): 3593–607. http://dx.doi.org/10.1200/jco.2004.10.216.

Full text

Abstract:

To date, our understanding of the role of receptors and their cognate ligands in cancer is being successfully translated into the design and development of an arsenal of new, less toxic, and more specific anticancer drugs. Because most of these novel drugs are cytostatic, objective response as measured by morphologic imaging modalities (eg, computed tomography or magnetic resonance imaging) cannot be used as a surrogate marker for drug development or for clinical decision making. Positron emission tomography (PET) can be used to image and quantify the in vivo distribution of positron-emitting radioisotopes such as oxygen-15, carbon-11, and fluorine-18 that can be substituted or added into biologically relevant and specific receptor radioligands. Similarly, single-photon emission computed tomography (SPECT) can be used to image and quantify the in vivo distribution of receptor targeting compounds labeled with indium-111, technetium-99m, and iodine-123. By virtue of their whole-body imaging capacity and the absence of errors of sampling and tissue manipulation as well as preparation, both techniques have the potential to address locoregional receptor status noninvasively and repetitively. This article reviews available data on the in vivo evaluation of receptor systems by means of PET or SPECT for identifying and monitoring patients with sufficient receptor overexpression for tailored therapeutic interventions, and also for depicting tumor tissue and determining the currently largely unknown heterogeneity in receptor expression among different tumor lesions within and between patients.

APA, Harvard, Vancouver, ISO, and other styles

33

Shen, Nan, Jing Liang, Xiaoni Qu, Sha Liu, Lin Zhu, Sheng Zhang, Ling Chen, Jiangwei Zhang, Dengwei Hu, and Bing Yin. "The influence of organic bases and substituted groups on coordination structures affording two mononuclear Dy(iii) single-molecule magnets (SMMs) and a novel Dy(iii)–K(i) compound with unusually coordinated fluorine atoms." CrystEngComm 23, no. 22 (2021): 4013–27. http://dx.doi.org/10.1039/d1ce00431j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Sasaki, Shigeki, Nobuyasu Ishibashi, Tshuneo Kuwamura, Hiromi Sano, Masaki Matoba, Tohru Nisikawa, and Minoru Maeda. "ChemInform Abstract: Excellent Acceleration of the Diels-Alder Reaction by Microwave Irradiation for the Synthesis of New Fluorine-Substituted Ligands of NMDA Receptor." ChemInform 30, no. 10 (June 17, 2010): no. http://dx.doi.org/10.1002/chin.199910154.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Zhu, Guangqian, Xianhui Zhang, Mengmeng Zhao, Liang Wang, Chuyang Jing, Peng Wang, Xiaowu Wang, and Qinggang Wang. "Influences of Fluorine Substituents on Iminopyridine Fe(II)- and Co(II)-Catalyzed Isoprene Polymerization." Polymers 10, no. 9 (August 22, 2018): 934. http://dx.doi.org/10.3390/polym10090934.

Full text

Abstract:

A series of iminopyridine complexes of Fe(II) and Co(II) complexes bearing fluorinated aryl substituents were synthesized for the polymerization of isoprene. The structures of complexes 3a, 2b and 3b were determined by X-ray diffraction analysis. Complex 3a contained two iminopyridine ligands coordinated to the iron metal center forming an octahedral geometry, whereas 2b adopted a chloro-bridged dimer, and 3b featured with two patterns of cobalt centers bridged via chlorine atoms. Complexes 2b and 3b represented rare examples of chlorine bridged bimetallic Co(II) complexes. The fluorine substituents effects, particularly on catalytic activity and polymer properties such as molecular weight and regio-/stereo-selectivity were investigated when these complexes were employed for isoprene polymerization. Among the Fe(II)/methylaluminoxane (MAO) systems, the 4-CF3 substituted iminopyridine Fe(II) complex 1a was found as a highly active isoprene polymerization catalyst exhibiting the highest activity of 106 g·(mol of Fe)−1·h−1. The resultant polymer displayed lower molecular weight (Mn = 3.5 × 104 g/mol) and moderate polydispersity index (PDI = 2.1). Furthermore, the ratio of cis-1,4-/3,4 was not affected by the F substituents. In the series of Co(II)/AlEt2Cl binary systems, complexes containing electron-withdrawing N-aryl substituents (R = 4-CF3, 2,6-2F) afforded higher molecular weights polyisoprene than that was obtained by the complex containing electron-donating N-alkyl substituents (R = octyl). However, ternary components system, complex/MAO/[Ph3C][B(C6F5)4] resulted in low molecular weight polyisoprene (Mn < 2000) with high trans-1,4-unit (>95%).

APA, Harvard, Vancouver, ISO, and other styles

36

Seo, Jai Woong, John S. Comninos, Dae Yoon Chi, Dong Wook Kim, Kathryn E. Carlson, and John A. Katzenellenbogen. "Fluorine-Substituted Cyclofenil Derivatives as Estrogen Receptor Ligands: Synthesis and Structure−Affinity Relationship Study of Potential Positron Emission Tomography Agents for Imaging Estrogen Receptors in Breast Cancer." Journal of Medicinal Chemistry 49, no. 8 (April 2006): 2496–511. http://dx.doi.org/10.1021/jm0512037.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Meinema, Harry A., Klaas Timmer, Hans L. Linden, and Carel I. M. A. Spee. "Synthetic Strategies for MOCVD Precursors for HTcS Thin Films." MRS Proceedings 335 (1993). http://dx.doi.org/10.1557/proc-335-193.

Full text

Abstract:

AbstractIn recent years much attention has been given world-wide to the development of suitable MOCVD precursors for the deposition of HTcS thin films. Synthetic research has been and is concentrated on the development of superior Ba-, Sr-, Ca- and Y-precursors. Most emphasis is given to the synthesis of thermally stable volatile barium compounds. Synthetic strategies are based on encapsulating the central metal atom, by use of multidentate ligand systems and/or bulky substituents. Most attention is given to the development of thermally stable volatile ß-diketonate complexes, fluorine-free and fluorine-substituted, with auxiliary ligands. Thermally stable monomeric complexes of fluorine-substituted ß-diketonates with polyethers are by far the most volatile Ba-, Sr-, and Ca-precursors presently available. Low melting Y(thd)3.L complexes where L is 4-Et- or 4-t-Bupyridine- N-oxide can be used as liquid yttrium MOCVD precursors at temperatures above 100°C. This paper gives a survey of the trends in recent research activity and developments in these areas.

APA, Harvard, Vancouver, ISO, and other styles

38

Spee, Carel I. M. A., Hans L. Linden, Adri Mackor, Klaas Timmer, and Harry A. Meinema. "Development of Novel Nickel(β-Diketonate)2.Ligand Complexes as Precursors for Mocvd of Nickel and Nickel Oxide." MRS Proceedings 415 (1995). http://dx.doi.org/10.1557/proc-415-93.

Full text

Abstract:

ABSTRACTVolatile and thermally stable nickel complexes have been prepared by the reaction of fluorine substituted, nickel β–diketonates with neutral (poly)oxygen and (poly)nitrogen donor ligands.These complexes, which have low melting points, have been applied as precursors in MOCVD experiments directed on nickel and nickel oxide deposition. Investigations into the deposition of NiO in porous YSZ via particle precipitation MOCVD, for the development of an anode for a planar Solid Oxide Fuel Cell, are reported.

APA, Harvard, Vancouver, ISO, and other styles

39

Essalah, K., M. A. K. Sanhoury, M. T. Ben Dhia, and M. R. Khaddar. "Beryllium (II) Chloride Complexes with Phosphoryl Ligands: A DFT Study." International Research Journal of Pure and Applied Chemistry, February 26, 2021, 38–46. http://dx.doi.org/10.9734/irjpac/2021/v22i130366.

Full text

Abstract:

Beryllium complexes of the types [BeCl2L2] (L = (Me2N)3P(O) (1), (Me2N)2P(O)F (2), Me2NP(O)F2 (3) and P(O)F3 (4)) have been theoretically studied by means of DFT geometry optimization and NMR chemical shift calculations (B3LYP/6-31G(d)). A good correlation was found between calculated and experimental data for complex 2. On going from complex 1 to 4, the Be-L bond underwent considerable lengthening, while that of Be-Cl was shortened (Be-O: 1.646 in 1 vs. 1.740 A° in 4; Be-Cl: 2.043 in 1 vs. 1.953 A° in 4). In the same way, the Be-O-P bond angle was found to decrease from 135° for 1 to 124° for 4. The trends are in good agreement with the calculated metal-ligand binding energies of complexes 1-4. Interestingly, the structural changes are accompanied by increased 9Be chemical shifts towards higher frequencies as the Me2N groups in the ligand are substituted by fluorine atoms. The results were compared to corresponding complexes with tin (IV) chloride, [SnCl4L2]. The theoretical data showed that the use of the 6-31G* basis set could efficiently predict the 9Be NMR chemical shifts in the complexes [BeCl2L2].

APA, Harvard, Vancouver, ISO, and other styles

40

Stoesser, Julian, and Stefan Huber. "Synthesizing highly fluorinated oligophenyls via Negishi coupling of fluoroarylzinc pivalates." Synthesis, September 17, 2021. http://dx.doi.org/10.1055/a-1647-6973.

Full text

Abstract:

Previously established general synthetic methods for the synthesis of highly fluorinated biphenyls using Suzuki-Miyaura protocols require the use of organoboron compounds which are not very stable under reactions conditions and thus need to be used in large excess. Herein we report an improved general strategy for the synthesis of highly fluorinated biphenyls, terphenyls and phenyl-substituted terphenyls using organozinc pivalates. The influence of several parameters was investigated: a) in a series of different monodentate phosphine ligands, X-Phos showed the best performance; b) a higher yield could be obtained for substrates bearing less steric hindrance or lower amount of fluorine substitution; c) as iodinated substrates decomposed during the reaction, brominated electrophiles were found to be superior. The presented protocol is scalable, versatile, and works with commonly used and commercially available phosphine ligands (X Phos) and palladium sources (Pd2dba3). Also, it does not need excess nucleophile usage for terphenyl synthesis and only a slight such excess for the preparation of phenyl substituted terphenyls.

APA, Harvard, Vancouver, ISO, and other styles

41

Bowen, Christina L., and Bradley M. Wile. "Dioxidomolybdenum(VI) complex featuring a 2,4-difluoro-substituted amine bis(phenolate) ligand." IUCrData 6, no. 5 (May 21, 2021). http://dx.doi.org/10.1107/s2414314621005162.

Full text

Abstract:

Synthetic complexes containing a cis-[MoO2]2+ core are well-established models for the molybdenum co-factor (Moco). Here we report the crystal structure of such a model complex bearing a tetradentate amine bis(phenolate) ligand with fluorine substituents on the phenolate rings, namely, [2,2′-({[2-(dimethylamino)ethyl]azanediyl}bis(methylene))bis(4,6-difluorophenolato)]dioxidomolybdenum(VI)), [Mo(C18H18F4N2O2)O2]. Distortion from idealized octahedral symmetry about the Mo center is evident in the large O=Mo=O angle [108.54 (4)°] and the small N–Mo–Ophenolate angles [79.79 (4), 81.21 (3), 77.83 (3), and 84.59 (3)°]. The dihedral angle between the phenolate rings is 60.06 (4)°, and π–π stacking is observed between aromatic rings related by inversion (1 − x, 1 − y, 1 − z). The lower data-collection temperature of 150 K vs room-temperature data collection reported previously [KOWXIF; Cao et al. (2014). Transit. Met. Chem. 39, 933–937] and larger 2θ range for data collection (5.8–66.6° versus 6–54.96°) led to a structure with lower R 1 and ωR 2 values (0.019 and 0.049 vs 0.0310 and 0.0566 for KOWXIF). Comparison of the metrical parameters with KOWXIF suggests that this dataset offers a more realistic depiction of bonding within the MoVI=O moiety.

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!