Relevant bibliographies by topics / Hydroxypyridine ligands

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Academic literature on the topic 'Hydroxypyridine ligands'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Hydroxypyridine ligands"

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Breit, Bernhard, and Wolfgang Seiche. "Self-assembly of bidentate ligands for combinatorial homogeneous catalysis based on an A-T base pair model." Pure and Applied Chemistry 78, no. 2 (January 1, 2006): 249–56. http://dx.doi.org/10.1351/pac200678020249.

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A new concept for generation of chelating ligand libraries for homogeneous metal complex catalysis based on self-assembly is presented. Thus, self-assembly of structurally simple monodentate ligands in order to give structurally more complex bidentate ligands is achieved employing hydrogen bonding. Based on this concept and on the 2-pyridone/hydroxypyridine tautomeric system, a new rhodium catalyst was identified which operated with excellent activity and regioselectivity upon hydroformylation of terminal alkenes. In order to generate defined unsymmetrical heterodimeric ligands, an A-T base pair analog-the aminopyridine/isoquinolone system-was developed which allows for complementary hydrogen bonding. Based on this platform, a 4 x 4 phosphine ligand library was screened in the course of the rhodium-catalyzed hydroformylation of 1-octene. A catalyst operating with outstanding activity and regioselectivity in favor of the linear aldehyde was discovered.
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Kremer, Marius, and Ulli Englert. "Zn and Ni complexes of pyridine-2,6-dicarboxylates: crystal field stabilization matters!" Acta Crystallographica Section E Crystallographic Communications 75, no. 6 (May 31, 2019): 903–11. http://dx.doi.org/10.1107/s2056989019007461.

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Six reaction products of ZnII and NiII with pyridine-2,6-dicarboxylic acid (H2Lig1), 4-chloropyridine-2,6-dicarboxylic acid (H2Lig2) and 4-hydroxypyridine-2,6-dicarboxylic acid (H2Lig3) are used to pinpoint the structural consequences of crystal field stabilization by an incomplete d shell. The pseudo-octahedral ZnII coordination sphere in bis(6-carboxypicolinato)zinc(II) trihydrate, [Zn(C7H4NO4)2]·3H2O or [Zn(HLig1)2]·3H2O, (1), is significantly less regular than that about NiII in the isostructural compound bis(6-carboxypicolinato)nickel(II) trihydrate, [Ni(C7H4NO4)2]·3H2O or [Ni(HLig1)2]·3H2O, (2). The ZnII complexes poly[(4-chloropyridine-2,6-dicarboxylato)zinc(II)], [Zn(C7H2ClNO4)] n or [Zn(Lig2)] n , (3), and poly[[(4-hydroxypyridine-2,6-dicarboxylato)zinc(II)] monohydrate], {[Zn(C7H3NO5)]·H2O} n or {[Zn(Lig3)]·H2O} n , (4), represent two-dimensional coordination polymers with chelating and bridging pyridine-2,6-dicarboxylate ligands in which the coordination polyhedra about the central cations cannot be associated with any regular shape; their coordination environments range between trigonal–bipyramidal and square-pyramidal geometries. In contrast, the corresponding adducts of the diprotonated ligands to NiII, namely triaqua(4-chloropyridine-2,6-dicarboxylato)nickel(II), [Ni(C7H2ClNO4)(H2O)3] or [NiLig2(OH2)3)], (5), and triaqua(4-hydroxypyridine-2,6-dicarboxylato)nickel(II) 1.7-hydrate, [Ni(C7H3NO5)(H2O)3]·1.7H2O or [NiLig3(OH2)3)]·1.7H2O, (6), feature rather regular octahedral coordination spheres about the transition-metal cations, thus precluding the formation of analogous extended structures.
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Bare, William D., Nathan H. Mack, J. N. Demas, and B. A. DeGraff. "pH-Dependent Photophysical Behavior of Rhenium Complexes Containing Hydroxypyridine Ligands." Applied Spectroscopy 58, no. 9 (September 2004): 1093–100. http://dx.doi.org/10.1366/0003702041959316.

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Oh, Yunghee, Chul Ho Lee, Burm Jong Lee, and Byoung Chul Shin. "Photoluminescent Europium Complexes with Oxygen and/or Nitrogen Donating Ligands." Key Engineering Materials 277-279 (January 2005): 966–71. http://dx.doi.org/10.4028/www.scientific.net/kem.277-279.966.

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The reaction of EuX3 ·nH2O (X=Cl¯ , NO3¯ ), a- pyridoin anion (P) and 2,2¢-dipyridylamine in ethanol solution yields a hydroxo complex, EuP2(OH) 2(H2O) 2, which is characterized by NMR, IR, and elemental analyses. Europium complexes coordinated by nitrogen donating ligands such as 2,2¢-dipyridylamine or 2¢-hydroxypyridine are unstable in solution and are prone to decompose to europium hydroxo complex and pyridinium amine salt. The UV and PL spectra of europium complexes are reported and a decomposition mechanism is proposed.
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Perdih, Franc. "Copper(II) bis(4,4,4-trifluoro-1-phenylbutane-1,3-dionate) complexes with pyridin-2-one, 3-hydroxypyridine and 3-hydroxypyridin-2-one ligands: molecular structures and hydrogen-bonded networks." Acta Crystallographica Section C Structural Chemistry 73, no. 11 (October 19, 2017): 960–67. http://dx.doi.org/10.1107/s2053229617014875.

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Copper(II) bis(4,4,4-trifluoro-1-phenylbutane-1,3-dionate) complexes with pyridin-2-one (pyon), 3-hydroxypyridine (hpy) and 3-hydroxypyridin-2-one (hpyon) were prepared and the solid-state structures of (pyridin-2-one-κO)bis(4,4,4-trifluoro-3-oxo-1-phenylbutan-1-olato-κ2 O,O′)copper(II), [Cu(C10H6F3O2)2(C5H5NO)] or [Cu(tfpb-κ2 O,O′)2(pyon-κO)], (I), bis(pyridin-3-ol-κO)bis(4,4,4-trifluoro-3-oxo-1-phenylbutan-1-olato-κ2 O,O′)copper(II), [Cu(C10H6F3O2)2(C5H5NO)2] or [Cu(tfpb-κ2 O,O′)2(hpy-κO)2], (II), and bis(3-hydroxypyridin-2-one-κO)bis(4,4,4-trifluoro-3-oxo-1-phenylbutan-1-olato-κ2 O,O′)copper(II), [Cu(C10H6F3O2)2(C5H5NO2)2] or [Cu(tfpb-κ2 O,O′)2(hpyon-κO)2], (III), were determined by single-crystal X-ray analysis. The coordination of the metal centre is square pyramidal and displays a rare example of a mutual cis arrangement of the β-diketonate ligands in (I) and a trans-octahedral arrangement in (II) and (III). Complex (II) presents the first crystallographic evidence of κO-monodentate hpy ligation to the transition metal enabling the pyridine N atom to participate in a two-dimensional hydrogen-bonded network through O—H...N interactions, forming a graph-set motif R 2 2(7) through a C—H...O interaction. Complex (III) presents the first crystallographic evidence of monodentate coordination of the neutral hpyon ligand to a metal centre and a two-dimensional hydrogen-bonded network is formed through N—H...O interactions facilitated by C—H...O interactions, forming the graph-set motifs R 2 2(8) and R 2 2(7).
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Pivarcsik, Tamás, Gábor Tóth, Nikoletta Szemerédi, Anita Bogdanov, Gabriella Spengler, Jakob Kljun, Jerneja Kladnik, Iztok Turel, and Éva A. Enyedy. "Comparison of Solution Chemical Properties and Biological Activity of Ruthenium Complexes of Selected β-Diketone, 8-Hydroxyquinoline and Pyrithione Ligands." Pharmaceuticals 14, no. 6 (May 27, 2021): 518. http://dx.doi.org/10.3390/ph14060518.

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In this work, the various biological activities of eight organoruthenium(II) complexes were evaluated to reveal correlations with their stability and reactivity in aqueous media. Complexes with general formula [Ru(η6-p-cymene)(X,Y)(Z)] were prepared, where (X,Y) represents either an O,O-ligand (β-diketone), N,O-ligand (8-hydroxyquinoline) or O,S-pyrithione-type ligands (pyrithione = 1-hydroxypyridine-2(1H)-thione) with Cl− or 1,3,5-triaza-7-phosphaadamantane (PTA) as a co-ligand (Z). The tested complexes inhibit the chlamydial growth on HeLa cells, and one of the complexes inhibits the growth of the human herpes simplex virus-2. The chlorido complexes with N,O- and O,S-ligands displayed strong antibacterial activity on Gram-positive strains including the resistant S. aureus (MRSA) and were cytotoxic in adenocarcinoma cell lines. Effect of the structural variation on the biological properties and solution stability was clearly revealed. The decreased bioactivity of the β-diketone complexes can be related to their lower stability in solution. In contrast, the O,S-pyrithione-type complexes are highly stable in solution and the complexation prevents the oxidation of the O,S-ligands. Comparing the binding of PTA and the chlorido co-ligands, it can be concluded that PTA is generally more strongly coordinated to ruthenium, which at the same time decreased the reactivity of complexes with human serum albumin or 1-methylimidazole as well as diminished their bioactivity.
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Hejrani-Dalir, Ali, Masumeh Tabatabaee, and Ali Sheibani. "Synthesis and crystal structure of 2-amino-3-hydroxypyridinium dioxido(pyridine-2,6-dicarboxylato-κ3O2,N,O6)vanadate(V) and its conversion to nanostructured V2O5." Acta Crystallographica Section C Structural Chemistry 71, no. 2 (January 12, 2015): 89–92. http://dx.doi.org/10.1107/s2053229614027983.

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2-Amino-3-hydroxypyridinium dioxido(pyridine-2,6-dicarboxylato-κ3O2,N,O6)vanadate(V), (C5H7N2O)[V(C7H3NO4)O2] or [H(amino-3-OH-py)][VO2(dipic)], (I), was prepared by the reaction of VCl3with dipicolinic acid (dipicH2) and 2-amino-3-hydroxypyridine (amino-3-OH-py) in water. The compound was characterized by elemental analysis, IR spectroscopy and X-ray structure analysis, and consists of an anionic [VO2(dipic)]−complex and an H(amino-3-OH-py)+counter-cation. The VVion is five-coordinated by oneO,N,O′-tridentate dipic dianionic ligand and by two oxide ligands. Thermal decomposition of (I) in the presence of polyethylene glycol led to the formation of nanoparticles of V2O5. Powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of the synthesized powder.
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Argibay-Otero, Saray, Rosa Carballo, and Ezequiel M. Vázquez-López. "Crystal structure offac-tricarbonylchloridobis(4-hydroxypyridine)rhenium(I)–pyridin-4(1H)-one (1/1)." Acta Crystallographica Section E Crystallographic Communications 73, no. 10 (September 29, 2017): 1551–54. http://dx.doi.org/10.1107/s2056989017013512.

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The asymmetric unit of the title compound, [ReCl(C5H5NO)2(CO)3]·C5H5NO, contains one molecule of the complexfac-[ReCl(4-pyOH)2(CO)3] (where 4-pyOH represents 4-hydroxypyridine) and one molecule of pyridin-4(1H)-one (4-HpyO). In the molecule of the complex, the Re atom is coordinated to two N atoms of the two 4-pyOH ligands, three carbonyl C atoms, in a facial configuration, and the Cl atom. The resulting geometry is slightly distorted octahedral. In the crystal structure, both fragments are associated by hydrogen bonds; two 4-HpyO molecules bridge between two molecules of the complex using the O=C group as acceptor for two different HO– groups of coordinated 4-pyOH from two neighbouring metal complexes. The resulting square arrangements are extented into infinite chains by hydrogen bonds involving the N—H groups of the 4-HpyO molecule and the chloride ligands. The chains are further stabilized by π-stacking interactions.
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9

Jotani, Mukesh M., Hadi D. Arman, Pavel Poplaukhin, and Edward R. T. Tiekink. "Bis(N,N-diethyldithiocarbamato-κ2S,S′)(3-hydroxypyridine-κN)zinc and bis[N-(2-hydroxyethyl)-N-methyldithiocarbamato-κ2S,S′](3-hydroxypyridine-κN)zinc: crystal structures and Hirshfeld surface analysis." Acta Crystallographica Section E Crystallographic Communications 72, no. 12 (November 1, 2016): 1700–1709. http://dx.doi.org/10.1107/s205698901601728x.

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The common feature of the molecular structures of the title compounds, [Zn(C5H10NS2)2(C5H5NO)], (I), and [Zn(C4H8NOS2)2(C5H5NO)], (II), are NS4donor sets derived fromN-bound hydroxypyridyl ligands and asymmetrically chelating dithiocarbamate ligands. The resulting coordination geometries are highly distorted, being intermediate between square pyramidal and trigonal bipyramidal for both independent molecules comprising the asymmetric unit of (I), and significantly closer towards square pyramidal in (II). The key feature of the molecular packing in (I) is the formation of centrosymmetric, dimeric aggregates sustained by pairs of hydroxy-O—H...S(dithiocarbamate) hydrogen bonds. The aggregates are connected into a three-dimensional architecture by methylene-C—H...O(hydroxy) and methyl-C—H...π(chelate) interactions. With greater hydrogen-bonding potential, supramolecular chains along thecaxis are formed in the crystal of (II), sustained by hydroxy-O—H...O(hydroxy) hydrogen bonds, with ethylhydroxy and pyridylhydroxy groups as the donors, along with ethylhydroxy-O—H...S(dithiocarbamate) hydrogen bonds. Chains are connected into layers in theacplane by methylene-C—H...π(chelate) interactions and these stack along thebaxis, with no directional interactions between them. An analysis of the Hirshfeld surfaces clearly distinguished the independent molecules of (I) and reveals the importance of the C—H...π(chelate) interactions in the packing of both (I) and (II).
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Al-Saeedi, Sameerah, Laila Abdel-Rahman, Ahmed Abu-Dief, Shimaa Abdel-Fatah, Tawfiq Alotaibi, Ali Alsalme, and Ayman Nafady. "Catalytic Oxidation of Benzyl Alcohol Using Nanosized Cu/Ni Schiff-Base Complexes and Their Metal Oxide Nanoparticles." Catalysts 8, no. 10 (October 13, 2018): 452. http://dx.doi.org/10.3390/catal8100452.

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In this work, nanosized Cu and Ni Schiff-base complexes, namely ahpvCu, ahpnbCu, and ahpvNi, incorporating imine ligands derived from the condensation of 2-amino-3-hydroxypyridine, with either 3-methoxysalicylaldehyde (ahpv) or 4-nitrobenzaldehyde (ahpnb), were synthesized using sonochemical approach. The structure and properties of the new ligands and their complexes with Ni(II) and Cu(II) were determined via infrared (IR), nuclear magnetic resonance (NMR), electronic spectra (UV-Vis), elemental analysis (CHN), thermal gravimetric analysis (TGA), molar conductivity (Λm), and magnetic moment (μeff). The combined results revealed the formation of 1:1 (metal: ligand) complexes for ahpvCu and ahpvNi and 1:2 for ahpnbCu. Additionally, CuO and NiO nanoparticles were prepared by calcination of the respective nanosized Cu/Ni complexes at 500 °C, and characterized by powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). Significantly, the as-prepared nanosized Schiff-base Cu/Ni complexes and their oxides showed remarkable catalytic activity towards the selective oxidation of benzyl alcohol (BzOH) in aqueous H2O2/ dimethylsulfoxide (DMSO) solution. Thus, catalytic oxidation of BzOH to benzaldehyde (BzH) using both ahpvCu complex and CuO nanoparticles in H2O2/DMSO media at 70 °C for 2 h yielded 94% and 98% BzH, respectively, with 100% selectivity.
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Dissertations / Theses on the topic "Hydroxypyridine ligands"

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Farhad, Mohammad. "Studies on new trinuclear palladium compounds." Connect to full text, 2007. http://hdl.handle.net/2123/2477.

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Doctor of Philosophy(PhD)
The present study deals with the synthesis and characterization of six tri-palladium complexes code named MH3, MH4, MH5, MH6, MH7 and MH8 that contained two planaramine ligands bound to the central or each of the terminal metal ions. The activity of the compounds against human cancer cell lines: A2780, A2780cisR and A2780ZD0473R, cell uptake, levels of DNA-binding and nature of interaction with salmon sperm and pBR322 plasmid DNA have also been determined. Whereas cisplatin binds with DNA forming mainly intrastrand GG adduct that causes local bending of a DNA strand, the tri-palladium complexes are expected to bind with DNA forming a number of long-range interstrand GG adducts that would cause a global change in DNA conformation. Among the designed complexes, MH6 that has two 2-hydroxypyridine ligands bound to each of the two terminal palladium ions is found to be most active. The compound also has the highest cell uptake and Pd-DNA binding levels. In contrast, MH8 which has two 4-hydroxypyridine ligands bound to each of the two terminal palladium ions is found to be least active. The results indicate that, as applied to the terminal metal centres, 2-hydroxypyridine would be more activating than 4-hydroxypyridine perhaps because of greater protection provided to the terminal centres from coming in contact with the solvent molecules. In contrast, when bound to the central metal centre, 4-hydroxypyridine appears to play a slightly greater activating role than 2-hydroxypyridine or 3-hydroxypyridine, suggesting that non-covalent interactions such as hydrogen bonding associated with the ligand rather than its steric effect may be a more important determinant of antitumour property. The results illustrate structure-activity relationships and suggest that the tri-palladium complex containing two 2-hydroxypyridine ligands bound to each of the three metal centres or the compound that contains two 2-hydroxypyridine ligands bound to each of the two terminal metal centres and two 4-hydroxypyridine ligands bound to the central metal centre, may be much more active than any of the designed complexes.
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Book chapters on the topic "Hydroxypyridine ligands"

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) bromo complex with 1-hydroxypyridine-2-thione." In Magnetic Properties of Paramagnetic Compounds, 164. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_81.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of copper(II) mixed ligand complex with thiophene-2-aldehyde thiosemicarbazone and 2-hydroxypyridine." In Magnetic Properties of Paramagnetic Compounds, 495. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_291.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) chloro complex with 1-hydroxypyridine-2-thione and triphenylphosphine." In Magnetic Properties of Paramagnetic Compounds, 154–55. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_76.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) bromo complex with 1-hydroxypyridine-2-thione and triphenylphosphine." In Magnetic Properties of Paramagnetic Compounds, 165–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_82.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) chloro complex with 1-hydroxypyridine-2-thione and bis(diphenylphosphino)methane." In Magnetic Properties of Paramagnetic Compounds, 156–57. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_77.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) bromo complex with 1-hydroxypyridine-2-thione and bis(diphenylphosphino) methane." In Magnetic Properties of Paramagnetic Compounds, 167–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_83.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) chloro complex with 1-hydroxypyridine-2-thione and 1,2-bis(diphenylphosphino)ethane." In Magnetic Properties of Paramagnetic Compounds, 158–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_78.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) chloro complex with 1-hydroxypyridine-2-thione and 1,2-bis(diphenylphosphino)propane." In Magnetic Properties of Paramagnetic Compounds, 160–61. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_79.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) chloro complex with 1-hydroxypyridine-2-thione and 1,2-bis(diphenylphosphino)butane." In Magnetic Properties of Paramagnetic Compounds, 162–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_80.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of mixed ligand copper(II) bromo complex with 1-hydroxypyridine-2-thione and 1,2-bis(diphenylphosphino)ethane." In Magnetic Properties of Paramagnetic Compounds, 169–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54237-8_84.

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Conference papers on the topic "Hydroxypyridine ligands"

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Bare, William D., Nathan H. Mack, James N. Demas, and Benjamin A. DeGraff, Jr. "Highly efficient pH-induced intramolecular quenching of luminescence in rhenium complexes containing the hydroxypyridinde ligand." In Environmental and Industrial Sensing, edited by Tuan Vo-Dinh and Robert L. Spellicy. SPIE, 2001. http://dx.doi.org/10.1117/12.417357.

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