0000000001309260

AUTHOR

Robert P. Doyle

Spin canting in an unprecedented three-dimensional pyrophosphate- and 2,2'-bipyrimidine-bridged cobalt(II) framework.

The three-dimensional cobalt(ii) compound of formula {[Co(2)(P(2)O(7))(bpym)(2)].12H(2)O}(n), where the pyrophosphate and 2,2'-bipyrimidine act as bridging ligands, is a new example of a spin-canted antiferromagnet with T(c) = 19 K.

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Ferromagnetic Coupling in “Double-Bridged” Dihydrogenpyrophosphate Complexes of Cobalt(II) and Nickel(II)

Three isostructural compounds of the formula {[M(bipy)(H2O)(H2P2O7)]2·2H2O} [bipy = 2,2'-bipyridine; M = Ni (1), Co (2), Mn (3)] have been isolated from aqueous solutions containing the corresponding metal(II) chloride hydrate with a bipy and sodium pyrophosphate solution in a 1:1:2 molar ratio, and their structures were determined by single-crystal X-ray diffraction. The structures of 1-3 consist of neutral aqua(2,2'-bipyridine)metal(II) dinuclear units bridged by two dihydrogenpyrophosphate groups adopting a bidentate/monodentate mode. Each metal ion in 1-3 is six-coordinate in a distorted octahedral geometry, with the reduced value of the angle subtended by the chelating bipy at the meta…

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Metamorphosis of a butterfly: synthesis, structural, thermal, magnetic and DFT characterisation of a ferromagnetically coupled tetranuclear copper(ii) complex

The reaction in water of Cu(OH)(2) with 2,2'-bipyridine (bipy) and (NH(4))(2)HPO(4) in a 4 : 4 : 2 molar ratio under an inert atmosphere leads to the formation of a tetranuclear copper(II) complex of formula {[(H(2)O)(2)Cu(4)(bipy)(4)(mu(4)-PO(4))(2)(mu(2)-OH)] x 0.5 HPO(4) x 15.5 H(2)O}, 1, with butterfly topology. The structure of the tetranuclear core in 1 consists of four crystallographically unique copper(II) ions in approximate square-pyramidal geometry with each coordinated to a bipy ligand and interacting through two mu(4)-O,O',O''-phosphate bridges. Additional bridging between Cu(3) and Cu(4) is provided by a hydroxide ligand, whereas two water molecules cap the Cu(1) and Cu(2) squ…

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Synthesis, Structural, Thermal and Magnetic Characterization of a Pyrophosphato‐Bridged Cobalt(II) Complex

The reaction in water of CoII sulfate heptahydrate with 1,10-phenanthroline (phen) and sodium pyrophosphate (Na4P2O7) in a 2:4:1 stoichiometric ratio resulted in the crystallization of a neutral dinuclear CoII complex, {[Co(phen)2]2(μ-P2O7)}·6MeOH (1), as revealed by a single-crystal X-ray diffraction study. The bridging pyrophosphato ligand between the two [Co(phen)2]2+ units in a bis(bidentate) coordination mode places the adjacent metal centers at 4.857 A distance, and its conformation gives rise to intramolecular π–π stacking interaction between adjacent phen ligands. Indeed, intermolecular π–π stacking interactions between phen ligands from adjacent dinuclear complexes create a supramo…

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Pyrophosphate-mediated magnetic interactions in Cu(II) coordination complexes.

The reaction in water of Cu(NO(3))(2)·2.5H(2)O with 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), or 1,10-phenanthroline-5-amine (phenam), and sodium pyrophosphate (Na(4)P(2)O(7)), at various pHs, afforded three new copper(II)-pyrophosphate complexes, namely, {[Cu(bipy)(cis-H(2)P(2)O(7))](2)}·3H(2)O (1a), {[Cu(phen)(H(2)O)](4)(HP(2)O(7))(2)}(ClO(4))(2)·4H(2)O (2), and {[Cu(2)(phenam)(2)(P(2)O(7))](2)·25H(2)O}(n) (3). A solvent free crystalline phase of 1a was also isolated with formula {[Cu(bipy)(trans-H(2)P(2)O(7))](2)} (1b), which can be regarded as a pseudo-polymorph of 1a. Single crystal X-ray analyses revealed these compounds to have uncommon molecular architectures, with 3 being…

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A methylenediphosphonate bridged copper(II) tetramer: Synthesis, structural, thermal, and magnetic characterization of [Cu4(H2O)2(phen)4(μ-P2O6CH2)2]·21H2O

Abstract A novel tetracopper(II) complex namely, [Cu4(H2O)2(phen)4(μ-P2O6CH2)2]·21H2O (1) was synthesized by using copper(II) chloride, 1,10-phenanthroline (phen), and methylene diphosphonic acid (MDP). The structure of 1 was characterized by single crystal X-ray diffraction and spectroscopy. Compound 1 crystallizes in the triclinic system, P 1 ¯ space group and its crystal structure consists of neutral centrosymmetric tetranuclear copper(II)-methylene diphosphonate units where each peripheral {Cu(phen)(P2O6CH2)}2− fragment adopts the bidentate(Oeq-P-Oeq)/monodentate (Oax) bridging mode towards each of the two inner {Cu(phen)}2+ entities resulting in a “clamshell”-like orientation. The two …

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Synthesis, structural, thermal, and magnetic investigations of Co(II), Ni(II), and Mn(II) pyrophosphate chains

The reaction in water of cobalt(II), nickel(II) or manganese(II) chloride with 1,10-phenanthroline (phen) and sodium pyrophosphate (Na 4 P 2 O 7 ) at low pH (∼2) afforded three isostructural pyrophosphate complexes of an unprecedented one-dimensional typology, namely, {[M(phen)(H 2 O)(H 2 P 2 O 7 )]·H 2 O} n with M = Co( 1 ), Ni( 2 ) and Mn( 3 ). The di-hydrogen-pyrophosphate anion featured in these complexes adopts a rare bidentate/monodentate bridging mode leading to chain propagation. This unusual bridging pathway produces a metal–metal intra-chain separation of about 6.6–6.7 A for 1 – 3 , values much larger than the metal–metal distance across the classic bis-bidentate PPi in the parent…

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Coordination complexes incorporating pyrophosphate: Structural overview and exploration of their diverse magnetic, catalytic and biological properties

Abstract Current attention continues to revolve around the chemistry and biochemistry associated with polyphosphate anions because of their importance in biology. A pivotal intermediate within this family is the pyrophosphate tetraanion, P2O74−. Considering its biological relevance and the multidentate nature that makes it an ideal ligand in the field of the coordination chemistry, there is a growing interest in the use of this anion in building new class of molecules/compounds for different purposes. While the total number of characterized structures still remains modest, several new pyrophosphate-containing coordination complexes have been reported in the last decade, as well as different…

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A dihydrogen arsenate-mediated supramolecular network: crystal structure and magnetic properties of {[(bipy)Cu(μ-H2AsO4)(H2AsO4)]2}n

Treatment of an aqueous suspension of Cu(OH)2 and 2,2′-bipyridine (bipy) with either Na2HAsO4·7H2O (1∶1∶2) or As2O5 (1∶1∶1) yields single crystals of {[(bipy)Cu(μ-H2AsO4)(H2AsO4)]2}n, 1, on standing. The solid-state structure of 1 consists of a three dimensional supramolecular network, supported by a combination of coordination covalent, hydrogen bonding and face-to-face π–π interactions. Variable temperature magnetic susceptibility measurements reveal very weak antiferromagnetic coupling between Cu(II) centres across the dihydrogen arsenate bridges (J = −0.58 cm−1).

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Synthesis, Structural, Magnetic and Thermal Characterization of {[Cu(bipy)] 2 (μ‐HP 2 O 7 )(μ‐Cl)}·H 2 O

Copper(II) hydroxide reacts with 2,2′-bipyridine (bipy) and sodium pyrophosphate in a 2:2:1 stoichiometric ratio under ambient conditions at pH 1.6 in water. The resulting neutral dinuclear CuII complex features a bridging set containing bridging monoprotonated pyrophosphate and a monoatomic chloro bridge (making this the first pyrophosphate bridged coordination complex containing an alternate, additional halide bridge between the metal centers). Single-crystal X-ray diffraction studies revealed the complex to be {[Cu(bipy)]2(μ-HP2O7)(μ-Cl)}·H2O. The structure consists of a dimeric copper(II) system with each metal ion in a square pyramidal geometry. The asymmetric [Cu(bipy)]2+ units are br…

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Synthesis, X‐ray Structure, Thermal and Magnetic Behavior of [(bipy) 2 Ni 2 (μ‐Cl) 2 Cl 2 (H 2 O) 2 ]: The First Neutral Ferromagnetically Coupled Six‐Coordinate Dichlorido‐Bridged Nickel(II) Dimer

NiCl2·6H2O and 2,2′-bipyridine (bipy) (1:1) were allowed to react under ambient conditions in dimethyl sulfoxide in the presence of acetylacetone (Hacac). The resulting green solution was concentrated in vacuo, and a green solid was isolated by precipitation with cold acetone. X-ray quality crystals of [(bipy)2Ni2(μ-Cl)2(Cl)2(H2O)2] (1) were grown by subsequent vapor/liquid diffusion of acetonitrile into a methanolic solution for one week. The structure of 1 consists of a dimeric nickel system with each metal atom in an octahedral geometry. Both equatorial bridging and axial chlorine atoms are present in this neutral species. The nickel–nickel distance (3.441 A) is the shortest reported to …

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Synthetically persistent, self assembled [V(IV)2V(V)4] polyoxovanadates: facile synthesis, structure and magnetic analysis.

Slow diffusion in a H-tube at room temperature of a methanolic solution of [VO(acac)(2)] (Hacac = acetylacetone) and 1,10-phenanthroline (phen) or 2,2'-bipyridine (bipy) into an aqueous solution of sodium pyrophosphate (Na(4)P(2)O(7)) resulted in the serendipitous formation of X-ray quality crystals of mixed-valent, hexameric oxovanadates of general formula [V(6)O(12)(OCH(3))(4)(L)(4)]·solv [L = 1,10-phenanthroline (phen) for 1· 2CH(3)OH · 4H(2)O (1a), and 2,2'-bipyridine (bipy) for 2· 4H(2)O (2a)]. These were characterized by single-crystal X-ray diffraction, IR, elemental and thermogravimetric analysis (TGA). A facile, rationalized synthetic route for the isolation of 1a and 2a could be e…

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Hydrogen-bond tuning of ferromagnetic interactions: synthesis, structure and magnetic properties of polynuclear copper(ii) complexes incorporating p-block oxo-anions

The reaction of copper(II) hydroxide with 2,2'-bipyridine (bipy) (1 : 1) in alkaline aqueous solution (pH 14) at room temperature affords the alternating carbonate/hydroxo-bridged copper(II) polymeric chain compound {[Cu3(bipy)3(mu-OH)2(mu-CO3)2].11H2O}n, 1, as determined by single-crystal X-ray diffraction. The structure of 1 is built up from two similar centro-symmetric dinuclear [(bipy)Cu(mu-OH)]2 cores which link together via bridging carbonate groups to mononuclear [(bipy)Cu] fragments to form the chain. Interdigitation of adjacent chains through pi-pi interactions, which involve each bipy ligand, forms sheets that are separated by the water molecules of crystallisation. Variable-tempe…

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Exploring the biological, catalytic, and magnetic properties of transition metal coordination complexes incorporating pyrophosphate

Abstract Polyphosphate anions are ubiquitous in nature, none more so than the diphosphate tetra-anion P2O74−, commonly referred to as pyrophosphate (PPi). The past decade has seen a rise in the number of pyrophosphate coordination complexes synthesized and characterized, and the areas of research interest expanded to include magnetic, medicinal, nutraceutical, catalytic and bioinorganic. The aim of the present review is to collect and organize the multidisciplinary information of the inorganic pyrophosphate system paying special attention to the following points: (i) the structural diversity of the PPi-containing metal complexes from discrete species to coordination polymers, which is due t…

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CCDC 1046978: Experimental Crystal Structure Determination

Related Article: Tiffany J. Greenfield , Amanda E. Hoffman , Nadia Marino , Alan G. Goos , Francesc Lloret , Miguel Julve , and Robert P. Doyle|2015|Inorg.Chem.|54|6537|doi:10.1021/acs.inorgchem.5b00866

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CCDC 1046977: Experimental Crystal Structure Determination

Related Article: Tiffany J. Greenfield , Amanda E. Hoffman , Nadia Marino , Alan G. Goos , Francesc Lloret , Miguel Julve , and Robert P. Doyle|2015|Inorg.Chem.|54|6537|doi:10.1021/acs.inorgchem.5b00866

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CCDC 1046979: Experimental Crystal Structure Determination

Related Article: Tiffany J. Greenfield , Amanda E. Hoffman , Nadia Marino , Alan G. Goos , Francesc Lloret , Miguel Julve , and Robert P. Doyle|2015|Inorg.Chem.|54|6537|doi:10.1021/acs.inorgchem.5b00866

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CCDC 1892797: Experimental Crystal Structure Determination

Related Article: Tiffany J. Greenfield, Tamra Takemoto, Joan Cano, Francesc Lloret, Miguel Julve, Jon Zubieta, Robert P. Doyle|2019|Polyhedron|169|162|doi:10.1016/j.poly.2019.05.022

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