Search results for "metallacycle"

showing 10 items of 23 documents

[2]Catenanes and inclusion complexes derived from self-assembled rectangular PdII and PtII metallocycles

2012

New inclusion complexes and [2]catenanes were self-assembled from a fluorescent diazapyrenium based ligand, a PdII or PtII complex, and cyclic or acyclic electron rich aromatic guests in aqueous and organic media. The molecular rectangles display a π-deficient cavity suitable to incorporate π-donor aromatic systems. The inclusion complexes between the metallocycles and phenylenic (2a,b) and naphthalenic (3a,b–5a,b) derivatives were studied by NMR, UV-vis and fluorescence spectroscopy. The crystal structure of (3b) ⊂ 1a·6PF(6) confirmed the insertion of the guest into the cavity of the metallocycle. Following the same self-assembly strategy, the use of polyethers 6,7 as π-donors resulted in …

Aqueous solutionLigandChemistryStereochemistryCatenaneCrystal structureSettore CHIM/06 - Chimica OrganicaMetallacycleFluorescenceFluorescence spectroscopySelf assembledCatenanes inclusion complexes PdII PtII metallocyclesInorganic ChemistryCrystallographySettore CHIM/03 - Chimica Generale E Inorganica
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Complexation and Extraction of PAHs to the Aqueous Phase with a Dinuclear Pt II Diazapyrenium‐Based Metallacycle

2010

New palladium and platinum metallacycles have been synthesized by reaction between a 2,7-diazapyrenium-based ligand and Pd(II) and Pt(II) complexes. The inclusion complexes between the metallacycles and polycyclic aromatic hydrocarbons (PAHs) in CD(3)NO(2) and D(2)O were studied by NMR spectroscopy. The structures of the inclusion complexes of the Pt metallacycle as host with pyrene, phenanthrene, and triphenylene were confirmed by single crystal X-ray crystallography. The association constants between the Pt metallacycle and the selected PAHs were determined in CH(3)CN following the characteristic charge-transfer band displayed in their UV/Vis absorption spectrum. Although in aqueous solut…

Aqueous solutionLigandOrganic Chemistrychemistry.chemical_elementTriphenyleneGeneral ChemistryNuclear magnetic resonance spectroscopyMetallacyclePhotochemistryMedicinal chemistryCatalysisJob plotchemistry.chemical_compoundchemistryPyreneinclusion compounds metallacycles polycyclic aromatic hydrocarbons self-assembly supramolecular chemistryPalladiumChemistry – A European Journal
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An easy route to 1-germaindenes via a transmetallation zirconiumgermanium reaction

1993

Abstract Several 1-zirconaindenes ( 4 ) have been obtained easily by heating phenylmethylzirconocene with various symmetrical (R  R′  CH 3 , C 2 H 5 , n-C 3 H 7 , Si(CH 3 ) 3 and unsymmetrical (R  CH 3 , R′  Si(CH 3 ) 3 ) alkynes (RCCR′). Under similar experimental conditions, the ynamine, diethylaminotrimethylsilylethyne, led to a regioselective reaction. From the X-ray structure of the zirconaindene product, the trimethylsilyl group was found close to the zirconium atom. Compounds 4 with germanium tetrachloride afford new 1-germaindenes ( 7 ) characterized by 1 H and 13 C NMR and mass spectrometry, in good yield.

Bicyclic moleculeTrimethylsilylOrganic ChemistryInorganic chemistryRegioselectivityMetallacycleBiochemistryMedicinal chemistryInorganic Chemistrychemistry.chemical_compoundTransmetalationchemistryYield (chemistry)Materials ChemistryPhysical and Theoretical ChemistryGermanium tetrachlorideMetalloceneJournal of Organometallic Chemistry
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Electrochemical chiral recognition by microparticle coatings of Pd complexes with bridging cyclometalated phosphines

2008

Abstract The palladium(II) dinuclear complex with bridging cyclometalated phosphines, {Pd2[μ-(C6H4)PPh2]2(μ-O2CCH3)2} (Pd2L2), having a paddlewheel structure, is reversibly oxidized in CH2Cl2 to a dinuclear palladium(III) analogue via two successive one-electron steps. Solid state voltammetry of Pd2L2 in contact with aqueous electrolytes produce as one-electron oxidation with two competing mechanisms involving anion intercalation/anion binding between/to metal centres, chloride ions acting as inhibitors for the first pathway. R- and S-Pd2L2 produces a significant stereoselective electrocatalytic activity with respect to the oxidation of l - and d -glutamic acid in alkaline media.

ChemistryGeneral Chemical EngineeringInorganic chemistrychemistry.chemical_elementMetallacycleElectrochemistryElectrocatalystChlorideMetalchemistry.chemical_compoundvisual_artPolymer chemistryElectrochemistryvisual_art.visual_art_mediummedicineAnion bindingPhosphinemedicine.drugPalladiumElectrochimica Acta
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Synthesis ofo-thiatelluraphenylenezirconocenes. X-ray crystal structure of

1992

o-Thiatelluraphenylenezirconocene complexes were obtained in good yield by reaction of dilithiumo-benzenthiatelluride with zirconocene dichlorides. These compounds represent the first examples of heterodichalcogenaphenylene bent metallocences. They were characterized by spectroscopic methods and the effect on the n.m.r. results of stepwise substitution of one and two Te atoms for S is discussed.

ChemistryStereochemistryBent molecular geometryMetals and AlloysCrystal structureMetallacycleInorganic ChemistryCrystallographychemistry.chemical_compoundYield (chemistry)X-ray crystallographyMaterials ChemistryMoleculeMetalloceneOrganometallic chemistryTransition Metal Chemistry
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Cover Picture: Complexation and Extraction of PAHs to the Aqueous Phase with a Dinuclear Pt II Diazapyrenium‐Based Metallacycle (Chem. Eur. J. 41/201…

2010

Computational chemistryChemistryOrganic ChemistryExtraction (chemistry)Aqueous two-phase systemSupramolecular chemistryOrganic chemistryCover (algebra)General ChemistrySelf-assemblyMetallacycleCatalysisChemistry – A European Journal
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A C(π-hole)⋯Cl-Zn tetrel interaction driving a metal-organic supramolecular assembly

2020

A brominated pyrimidinyl triazolopyridine ligand (bptpy) forms a C(π-hole)⋯Cl-Zn tetrel interaction that plays a determining role in the formation of supramolecular layers through chain assembly in 18 membered metallacycle [(ZnCl2)2(μ-bptpy)2] crystals. Supramolecular chains are formed through C-H⋯X interactions. The observed interactions are supported by DFT calculations using model dimers. This journal is

CrystallographyChemistryLigandSupramolecular chemistryGeneral Materials ScienceTriazolopyridineGeneral ChemistryMetallacycleCondensed Matter PhysicsSupramolecular assemblyCrystEngComm 22: 6979-6982 (2020)
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Olefin metathesis reactions with fluorinated substrates, catalysts, and solvents.

2014

CyclodextrinsOlefin metathesisHalogenationLactamsChemistryHomogeneous catalysisStereoisomerismGeneral ChemistryMetallacycleAlkenesCatalysisCatalysisCyclooctanesOrganic reactionMetalsSphingosineSolventsRing-opening metathesis polymerisationOrganic chemistryPeptidesChemical reviews
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Synthesis of orthometallated rhodium(III) compounds. Crystal structures of [RhCl2{η2(C6H4)PPh2}(η2-dppm)] and [RhCl{η2(C6H4)PPh2}(η1-PCCl)(phen)] (…

1993

Abstract Neutral and cationic rhodium(III) metallated compounds containing a four-membered ring are prepared by different synthetic methods: (i) from rhodium(I) compounds that contain the ligand P( o -ClC 6 H 4 )PPh 2 , by 2c-2e intramolecular oxidative addition; (ii) from metallated dirhodium(II) compounds; (iii) by ligand substitution in [RhCl 2 {η 2 -(C 6 H 4 )PPh 2 }{η 2 -P( o -ClC 6 H 4 )Ph 2 }]. The crystal structures of [RhCl 2 {η 2 -(C 6 H 4 )PPh 2 }(η 2 -dppm)] ( 2 ) and of the dichloromethane solvate of [RhCl{η 2 -(C 6 H 4 )PPh 2 }{η 1 -P( o -ClC 6 H 4 )Ph 2 }(phen)](SbF 6 ) ( 11 ) have been determined by X-ray diffraction methods. In both complexes the Rh atom is in the distorted…

DenticityChemistryLigandStereochemistryPhenanthrolinechemistry.chemical_elementCrystal structureMetallacycleMedicinal chemistryOxidative additionRhodiumInorganic Chemistrychemistry.chemical_compoundMaterials ChemistryPhysical and Theoretical ChemistryPhosphineInorganica Chimica Acta
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Reactions of pyridine-2-carbaldimines with chloro-bridged palladium(II) and platinum(II) 2-methylallyl dimers. Solution behaviour of the cationic com…

1987

Abstract The reactions of pyridine-2-carbaldimines, py-2- CHNR (R = C6H4OMe-p, Me), with allylic dimers [MCl(n3-2-MeC3H4)]2 give rise to stoichiometry, concentration, solvent and temperature dependent equilibria, in which the cationic complexes [M(n3- 2-MeC3H4)(py-2-CHNR)]+ and the anion [MCl2(n3- 2-MeC3H4)]- or Cl- are involved. In general, the ligand/dimer reaction (1/1 molar ratio) yields the ionic products [M(n3-2-MeC3H4)(py-2-CHNR)]- [MCl2(n3-2-MeC3H4)], which can be isolated as solids, whereas the same reaction in a 1/0.5 molar ratio yields the species [M(n3-2-MeC3H4 )(py-2-CH NR)] Cl, which can be studied only in solution, but are easily converted into [M(n3-2-MeC3H4)(py-2-CH NR…

DimerInorganic chemistryCationic polymerizationchemistry.chemical_elementMetallacycleMedicinal chemistryInorganic ChemistrySolventchemistry.chemical_compoundchemistryPyridineMaterials ChemistryPhysical and Theoretical ChemistryPlatinumAcetonitrilePalladiumInorganica Chimica Acta
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