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BF4
Selected AbstractsGold(I) Complexes of P,N Ligands and Their Catalytic ActivityEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 7 2010Chosu Khin Abstract Gold(I) complexes were readily prepared by reaction of the respective ligands with (Me2S)AuCl in CH2Cl2. Complexes of formula LAuCl {L = diphenyl(2-pyridyl)phosphane (PPh2Py), (R)-(+)-4-[(2)-(diphenylphosphanyl)-1-naphthyl]- N -[(R)-1-phenylethyl]-1-phthalazinamine (PINAP)} were obtained when a 1:1 molar ratio of ligand to starting gold precursor was used. When a 2:1 ratio of ligand to gold precursor was used with PPh2Py or MandyPhos as ligands, complexes of the type L2AuCl were obtained. All complexes were fully characterized, and single-crystal X-ray structures could be determined for four complexes. Chloride ions were removed by reaction with silver salts, such as AgNTf2, AgOTf and AgBF4, for the use of these complexes as catalysts. After the catalytic reaction with alkynes and alcohols in acetonitrile, a unique trinuclear gold(I) complex derived from [(PPh2Py)Au]BF4 could be characterized by X-ray structural analysis, showing a mode of catalyst deactivation. [source] Six-Membered N-Heterocyclic Carbenes with a 1,1,-Ferrocenediyl Backbone: Bulky Ligands with Strong Electron-Donor Capacity and Unusual Non-Innocent CharacterEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 31 2009Ulrich Siemeling Abstract The stable, crystalline N-heterocyclic diaminocarbene fc[N(CH2tBu)-C-N(CH2tBu)] (2d, fc = 1,1,-ferrocenediyl) was prepared by deprotonation of its formamidinium precursor fc[N(CH2tBu)-CH-N(CH2tBu)][BF4] (1d) and used for the preparation of the 16 valence electron complexes [Mo(2d)(CO)4], [RhCl(2d)(cod)] (cod = 1,5-cyclooctadiene) and [RhCl(2d)(CO)2]. 1d, 2d and [RhCl(2d)(cod)] were structurally characterised by single-crystal X-ray diffraction studies. The electrochemical properties of 2d, its 2-adamantyl analogue 2c, its complex [RhCl(2d)(CO)2] and of the precursors 1d and 1,1,-bis(neopentylamino)ferrocene were investigated by electrochemistry. The carbenes are easily oxidised to the corresponding radical cation, whose persistent nature is unprecedented in the chemistry of N-heterocyclic carbenes. The spin density is located at the Fe atom and the carbene C atom according to the results of EPR spectroscopic studies and DFT calculations.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] 16-Electron (Arene)ruthenium Complexes with Superbasic Bis(imidazolin-2-imine) Ligands and Their Use in Catalytic Transfer HydrogenationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29-30 2009Thomas Glöge Abstract The ligands N,N, -bis(1,3,4,5-tetramethylimidazolin-2-ylidene)-1,2-ethanediamine (BLMe) and N,N, -bis(1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene)-1,2-ethanediamine(BLiPr) react with [(,5 -C5Me5)RuCl]4 to afford cationic 16-electron half-sandwich complexes [(,5 -C5Me5)Ru(BLR)]+ (R = Me, 3; R = iPr, 4), which resist coordination of the chloride counterion because of the strong electron-donating ability of the diimine ligands. Upon reaction with [(,6 -C6H6)RuCl2]2 or [(,6 -C10H14)RuCl2]2, these ligands stabilize dicationic 16-electron benzene and cymene complexes of the type [(,6 -C6H6)Ru(BLR)]2+ (R = Me, 5; R = iPr, 6) and [(,6 -C10H14)Ru(BLR)]2+ (R = Me, 7; R = iPr, 8). The X-ray crystal structure of [5]Cl2 reveals the absence of any direct Ru,Cl interaction, whereas a long Ru,Cl bond, supported by two CH···Cl hydrogen bonds, is observed for [(6)Cl]Cl in the solid state. Treatment of the dichlorides of 6 and 8 with NaBF4 affords [6](BF4)2 and [8](BF4)2, which are composed of individual dications and tetrafluoroborate ions with no direct Ru,F interaction. All complexes catalyze the transfer hydrogenation of acetophenone in boiling 2-propanol. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Cyanoimide-Bridged, Bi- and Trinuclear, Heterometallic Complexes with an NCN,Mo,NCN Phosphinic CoreEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 26 2009Sónia M. P. R. M. Cunha Abstract The heterometallic dinuclear complexes of the types trans -[Mo(NCN)(dppe)2(,-NCN)M] [M = WCl4(PPh3), ReOCl3(PPh3) or mer -ReCl(N2)(PMePh2)3; dppe = Ph2PCH2CH2PPh2] and [Mo(NCN)(dppe)2(,-NCN)M][BF4]Br [M = trans -Fe(NCC6H4NO2 -4)(depe)2; depe = Et2PCH2CH2PEt2] and the trinuclear ones [Mo(dppe)2{(,-NCN)M}2] [M = VCl3(thf) or PtCl2(PEt3)] were prepared by reaction of the bis(cyanoimido)molybdenum complex trans -[Mo(NCN)2(dppe)2] with the corresponding transition-metal Lewis acid (M) precursors, particularly [VCl3(thf)3], [WCl4(PPh3)2], [ReOCl3(PPh3)2], trans -[ReCl(N2)(PMePh2)4], trans -[FeBr(NCC6H4NO2 -4)(depe)2][BF4] and [Pt2Cl4(PEt3)2]. These adducts were characterized by FTIR, 1H, 13C and 31P{1H} NMR spectroscopy, mass spectrometry and cyclic voltammetry. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] The Variable Binding Modes of Phenylbis(pyrid-2-ylmethyl)phosphane and Bis(pyrid-2-ylmethyl) Phenylphosphonite with AgI and CuIEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 20 2009Fernando Hung-Low Abstract A series of new bridging phosphane and phosphonite structures forming three- and six-membered rings with the metal centers were synthesized and characterized. The resulting compounds of phenylbis(pyrid-2-ylmethyl)phosphane (1) with the silver(I) salts of trifluoroacetate (tfa,), tetrafluoroborate (BF4,), and trifluoromethanesulfonate (OTf,), and copper tetrakis(acetonitrile) hexafluorophosphate (PF6,) shows the flexibility of the ligand by displaying different coordination modes associated with the electronic and structural characteristics of the corresponding anion. Accordingly, ligand 1 in these complexes displays two different binding modes. With Agtfa and AgBF4 compounds 3 and 4 are obtained where the ligand chelates to two silver atoms that exhibit normalAg,Ag contacts in the range of 2.9 Å. When AgOTf or Cu(NCCH3)4PF6 are used, one molecule of 1 bridges the metal centers through a phosphorus atom while another is terminally bound. This induces short M,M distances of 2.6871 and 2.568 Å for 5 and 6, respectively. Similarly, the coordination behavior of the heterofunctional bis(pyrid-2-ylmethyl) phenylphosphonite ligand (2) is reported with Cu(NCCH3)4PF6 (7) and AgBF4 (8) to form two novel discrete molecules. In these complexes 2 coordinates through the P and N atoms, with the difference that in 7 the O atom of one of the carbinol arms is also bound to the Cu. Elemental analysis, variable-temperature multinuclear NMR spectroscopy, single-crystal X-ray diffraction, and low-temperature luminescence studies were carried out to fully characterize the compounds. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Mechanistic Insights into Acetophenone Transfer Hydrogenation Catalyzed by Half-Sandwich Ruthenium(II) Complexes Containing 2-(Diphenylphosphanyl)aniline , A Combined Experimental and Theoretical StudyEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 28 2008Alessia Bacchi Abstract Several new half-sandwich ruthenium(II) complexes containing 2-(diphenyphosphanyl)aniline (PNH2) of formula {Ru[(,2P,N)PNH2](p -cymene)Cl}Y [Y = Cl (1a), PF6 (1b), BF4 (1c), BPh4 (1d), TfO (1e)] were synthesized and fully characterized both in solution (1H NMR and 31P{1H} NMR spectroscopy) and in the solid state (FTIR, X-ray analysis on single crystal). Complexes 1a and 1b are active precatalysts in the hydrogen transfer reaction of acetophenone, leading to tof values up to 4440 h,1. In comparison, the {Ru[(,2P,N)PNMe2](p -cymene)Cl}Cl complex leads to a tof value of 100 h,1 under the same catalytic conditions. The mechanism through which the precatalysts operate was deeply explored by high-resolution MS (ESI) and DFT/PCM studies. The results reveal that the complexes containing PNH2 operate through a bifunctional mechanism analogous to that proposed for diamines and amino alcohol ligands. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Influence of the Diketonato Ligand on the Cytotoxicities of [Ru(,6 - p -cymene)(R2acac)(PTA)]+ Complexes (PTA = 1,3,5-triaza-7-phosphaadamantane)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2008Carsten A. Vock Abstract A series of compounds of general formula [Ru(,6 - p -cymene)(R2acac)(PTA)][X] (R2acac = Me2acac, tBu2acac, Ph2acac, Me2acac-Cl; PTA = 1,3,5-triaza-7-phosphaadamantane; X = BPh4, BF4), and the precursor to the Me2acac-Cl derivative [Ru(,6 - p -cymene)(Me2acac-Cl)Cl], have been prepared and characterised spectroscopically. Five of the compounds have also been characterised in the solid state by X-ray crystallography. The tetrafluoroborate salts are water-soluble, quite resistant to hydrolysis, and have been evaluated for cytotoxicity against A549 lung carcinoma and A2780 human ovarian cancer cells. The compounds are cytotoxic towards the latter cell line, and relative activities are discussed in terms of hydrolysis (less important) and lipophilicity, which appears to exert the dominating influence. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Cyanometalate Cages with Exchangeable Terminal LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2007Julie L. Boyer Abstract The coordination chemistry of the unusual metallo-ligand Cs,[CpCo(CN)3]4[Cp*Ru]3 (Cs,Co4Ru3) is described with attention to the behavior of the ligand itself, its binding to Lewis-acidic metal cations, and its ability to stabilize catalytically relevant Ru,PPh3 fragments. A series of tests demonstrate that the "rim" [CpCo(CN)3], groups in Cs,Co4Ru3 are exchangeable. Upon treatment with [(MeC5H4)Co(CN)3], (Co,) Cs,Co4Ru3 undergoes vertex exchange to give Cs,Co4,xCo,xRu3. Similarly the cage is degraded by CO. Most convincing, Cs,Co4Ru3 reacts with PhNH3OTf to precipitate the polymer PhNH3CpCo(CN)3 and form the molecular box [Cs,Co4Ru4]+. Treatment of Cs,Co4Ru3 with [M(NCMe)x]PF6 (M = Cu, Ag) gave the Lewis acidic cages {Cs,[CpCo(CN)3]4[Cp*Ru]3M(NCMe)}PF6, which reacted with tertiary phosphane ligands to give adducts [Cs,Co4Ru3M(PPh3)]PF6. Lewis acidic octahedral vertices were installed using Fe, Ni, and Ru reagents. The boxes [Cs,Co4Ru3M(NCMe)3]2+ (M = Ni, Fe) formed readily from the reaction Cs,Co4Ru3 with [Ni(NCMe)6](BF4)2 and [Fe(NCMe)6](PF6)2. Displacement of the MeCN ligands gives [Cs,Co4Ru3Ni(9-ane-S3)](BF4)2. A series of boxes were prepared by the reaction of Cs,Co4Ru3 and RuCl2(PPh3)3, RuHCl(PPh3)3, and [(C6H6)Ru(NCMe)3](PF6)2. The derivative of the hydride, [Cs,Co4Ru3Ru(NCMe)(PPh3)2](PF6)2, was characterized crystallographically.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Anion-Dependent Structural Diversity in Silver(I) Complexes of 4-Amino-3,5-diisopropyl-1,2,4-triazoleEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2007Guang Yang Abstract Reactions of silver salts with 4-amino-3,5-diisopropyl-1,2,4-triazole (L) afford dinuclear complex [Ag2L2(NO3)2(CH3CN)], triangular complex [Ag3L3](CF3SO3)3, and cyclic tetranuclear complexes [Ag4L6](BF4)4 and [Ag4L6](ClO4)4. On the basis of the X-ray analyses, anions are found to play an important role in determining the structures. Through coordination/noncoordination, anions can impart their influence on the coordination geometry of Ag atoms and the angles of N,Ag,N, which seems to be the main factor controlling the nuclearity of the reaction products in this system. 1H NMR and MS measurements suggest that these complexes probably retain their structural integrities in CH3CN solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Diastereopure Cationic NCN-Pincer Palladium Complexes with Square Planar ,4 - N,C,N,O CoordinationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2006Silvia Gosiewska Abstract Neutral NCN-pincer palladium bromide complex 2 containing the monoanionic, enantiopure pincer ligand 2,6-bis{[(S)-2-hydroxymethyl-1-pyrrolidinyl]methyl}phenyl bromide (1) with bis- ortho -(S)-prolinol substituents was synthesized and isolated as a mixture of three stereoisomers [(SN,SN,SC,SC), (RN,SN,SC,SC), and (RN,RN,SC,SC)] in a 1:1:1 ratio. Upon abstraction of the bromide ion from the unresolved mixture of 2, single diastereoisomers of the cationic complexes [3]BF4 and [3]PF6, respectively, were formed with a unique,4 - N,C,N,O coordination mode of ligand 1. X-ray crystal structure determination established the intramolecular,4 - N,C,N,O coordination of 1 to palladium where the typical mer -,3 - N,C,N pincer coordination is accompanied by coordination of one of the hydroxy groups of the (S)-prolinol moieties. The water molecule that was cocrystallized in the crystal structure of [3]PF6 does not coordinate to palladium, but instead is involved in a hydrogen bonding network. The catalytic potential of both cationic complexes, [3]BF4 and [3]PF6, was tested in an aldol reaction of aldehydes with methyl isocyanoacetate to yield the oxazoline products as racemic mixtures.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis, Complexation and Spectrofluorometric Studies of a New NS3 Anthracene-Containing Macrocyclic LigandEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2006Abel Tamayo Abstract A new fluorescent device for detecting protons and metal ions, 11-(9-anthracenylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L), has been synthesised. In addition, the photophysical properties of both the free and protonated species have been examined by absorption and fluorescence titrations of dichloromethane solutions of L with methanesulfonic acid. The coordinating properties of L toward PdII, ZnII, NiII and CoII have been studied both in solution and in the solid state. Different behaviours have been observed in the absorption and fluorescence titrations of L with the above-mentioned transition-metal ions. To evaluate whether these differences were due to the existence of equilibria between protonated and complexed species, such titrations have been repeated in the presence of an equivalent amount of acid. The structure of the [Pd(L)](BF4)2 complex has been solved by X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] The First Sandwich Complex with an Octa(thioether) Coordination Sphere: Bis(maleonitrile-tetrathia-12-crown-4)silver(I),EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 12 2006Hans-Jürgen Holdt Abstract The new tetrathiacrown ethers maleonitrile-tetrathia-12-crown-4 (mn12S4) and maleonitrile-tetrathia-13-crown-4 (mn13S4) have been prepared and characterised by X-ray crystallographic analysis. These crown ethers form 2:1, 3:2 and 1:1 complexes with AgY (Y = BF4, PF6). The crystal structures of [Ag(mn12S4)2]BF4 (3a), [Ag(mn13S4)2]BF4 (4a) and [Ag2(mn13S4)3](PF6)2 (6b) have been determined. Compound 3a contains the centrosymmetric sandwich complex cation [Ag(mn12S4)2]+ where each mn12S4 ligand is coordinated to the Ag centre in an endo manner through all four S atoms. The 2:1 complex [Ag(mn12S4)2]+ is the first sandwich complex with a tetrathiacrown ether and the first complex with an octa(thioether) coordination sphere. The crystal structure of compound 4a also reveals a 2:1 complex. This complex, [Ag(mn13S4)2]+, exhibits a half-sandwich structure. One mn13S4 ligand coordinates to Ag+ by all four S donor atoms and the other 13S4 crown by only one S atom. Compound 6b contains a dinuclear Ag complex. The Ag complexes 3a,b,8a,b were also studied by electrospray ionisation mass spectrometry. Collision-induced dissociation (CID) was used to compare the relative stability of 2:1 complexes [AgL2]+ and 1:1 complexes [AgL]+ (L = mn12S4, mn13S4). The 13C NMR chemical shifts of 2:1 and 1:1 Ag complexes and their corresponding free ligands were also estimated and compared. The free energy of the barrier of ring inversion (,G,) for [Ag(mn12S4)2]+ was determined to be 64 kJ,mol,1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Monophosphanylcalix[6]arene Ligands: Synthesis Characterization, Complexation, and Their Use in CatalysisEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2006Yasushi Obora Abstract Novel phosphanylcalix[6]arenes having mono- O -diphenylphosphanylmethyl (3) and mono- O -(4-diphenylphosphanylphenyl)methyl substituents (5) have been synthesized. The structures of these monophosphanylcalix[6]arenes were determined by NMR spectroscopy, mass spectrometry, and X-ray crystal structure analysis. The X-ray structure reveals that 3 adopts a flattened 1,2,3-alternate conformation in the crystalline state, while the NMR spectra show that 3 and 5 have a cone conformation in solution. Structure optimization and energy calculations for 3 and 5 at the B3LYP/LANL2DZ-CONFLEX5/MMFF94s level of theory show that the cone conformation is slightly more stable than the 1,2,3-alternate conformation by 0.36 kcal,mol,1 for 3 and 0.96 kcal,mol,1 for 5. Complexation of 3 with [PtCl2(COD)] and [Rh(COD)2]BF4 gives cis -coordinated [PtCl2(3)2] and [Rh(COD)(3)2]BF4, respectively. The X-ray analysis of [PtCl2(3)2] shows that 3 adopts a cone conformation upon complexation. Combination of 3 and 5 with [Rh(COD)2]BF4 provides an active catalyst for the hydroformylation of a variety of terminal alkenes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Water-Soluble Arene Ruthenium Complexes Containing a trans -1,2-Diaminocyclohexane Ligand as Enantioselective Transfer Hydrogenation Catalysts in Aqueous SolutionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2005Jérôme Canivet Abstract The cationic chloro complexes [(arene)Ru(H2N,NH2)Cl]+ (1: arene = C6H6; 2: arene = p -MeC6H4iPr; 3: arene = C6Me6) have been synthesised from the corresponding arene ruthenium dichloride dimers and enantiopure (R,R or S,S) trans -1,2-diaminocyclohexane (H2N,NH2) and isolated as the chloride salts. The compounds are all water-soluble and, in the case of the hexamethylbenzene derivative 3, the aqua complex formed upon hydrolysis [(C6Me6)Ru(H2N,NH2)OH2]2+ (4) could be isolated as the tetrafluoroborate salt. The molecular structures of 3 and 4 have been determined by single-crystal X-ray diffraction analyses of [(C6Me6)Ru(H2N,NH2)Cl]Cl and [(C6Me6)Ru(H2N,NH2)OH2][BF4]2. Treatment of [Ru2(arene)2Cl4] with the monotosylated trans -1,2-diaminocyclohexane derivative (TsHN,NH2) does not yield the expected cationic complexes, analogous to 1,3 but the neutral deprotonated complexes [(arene)Ru(TsN,NH2)Cl] (5: arene = C6H6; 6: arene = p -MeC6H4iPr; 7: arene = C6Me6; 8: arene = C6H5COOMe). Hydrolysis of the chloro complex 7 in aqueous solution gave, upon precipitation of silver chloride, the corresponding monocationic aqua complex [(C6Me6)Ru(TsHN,NH2)(OH2)]+ (9) which was isolated and characterised as its tetrafluoroborate salt. The enantiopure complexes 1,9 have been employed as catalysts for the transfer hydrogenation of acetophenone in aqueous solution using sodium formate and water as a hydrogen source. The best results were obtained (60 °C) with 7, giving a catalytic turnover frequency of 43 h,1 and an enantiomeric excess of 93,%. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Variability in the Structures of Luminescent [2-(Aminomethyl)pyridine]silver(I) Complexes: Effect of Ligand Ratio, Anion, Hydrogen Bonding, and ,-StackingEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2005Rodney P. Feazell Abstract The reaction of 2-(aminomethyl)pyridine (2-amp) with silver(I) salts of triflate (OTf,), trifluoroacetate (tfa,), and tetrafluoroborate (BF4,) produce monomeric, dimeric, bridged, and polymeric structural motifs. The structural characteristics are dependent upon the ratio of ligand/metal in the structure as well as the ability of the anion to coordinate to the metal centers and form hydrogen bonds to the bound ligands. The silver coordination environment takes on several geometries including near linear (6), trigonal (4), tetrahedral (1), and both trigonal-bipyramidal and square-based pyramidal in a single structure (2). Structures 2, 3, and 5 also display short Ag,Ag contacts ranging from 2.8958(3) to 3.0305(4) Å. The species with metal,metal interactions, which are connectively very similar to their metal-isolated counterparts of 1, 4, and 6, are held together only by weak ,-stacking interactions or hydrogen bonds to their respective anions. Low-temperature luminescence spectra were collected for all compounds and are compared. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Synthesis, Structure and Spectroscopic Properties of Novel9,10-Bis{[6-(diphenylphosphanyl)-2-pyridylmethyl]propylaminomethyl}anthracene-Bridged Group 11 Metal (M = CuI and AgI) Dinuclear ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2005Hu Xu Abstract Dinuclear complexes [M2(,-BPNNAn)]X2 (M = CuI, X = ClO4,1, X = BF4,2; M = AgI, X = BF4,3, X = ClO4,4) have been prepared by treating 9,10-bis{[6-(diphenylphosphanyl)-2-pyridylmethyl]propylaminomethyl}anthracene (BPNNAn) with M(CH3CN)4X in CH2Cl2. The structures of complexes 1, 2 and 3 have been determined by single-crystal X-ray diffraction studies. In the complexes, BPNNAn acts as a chelating ligand and two metal ions riding on two bridgehead carbon atoms in the anthracene group leads to the deformation of the anthracenyl ring. The Cu,Arene charge transfer interaction is observed from the nonfluorescent emission of Cu complex 1, while the Ag complex 3 exhibits dual emission at high concentrations in a CH2Cl2 solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Synthesis and Characterisation of New Iridium Complexes with the (4S)-2-[2-(Diphenylphosphanyl)phenyl]-4-isopropyl-1,3-oxazoline Ligand That Catalyse Asymmetric Michael ReactionsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2005Daniel Carmona Abstract The chiral iridium compounds [IrCl(COE){(S)-PN}] {COE = cyclooctene, PN = (4S)-2-[2-(diphenylphosphanyl)phenyl]-4-isopropyl-1,3-oxazoline, (1)}, [Ir(acac)ClH{(S)-PN}] {Hacac = acetylacetone, (2)} and [Ir{(S)-PN}2]A {A = Cl (3a,b); BF4 (4a,b); PF6 (5a,b)} have been prepared, characterised and employed as catalysts for the asymmetric Michael addition of keto or cyano esters to ,,,-unsaturated carbonyl compounds. The X-ray molecular structures of compounds 2 and 5b are reported. The model catalytic intermediates [IrH(NCCHCO2R){(S)-PN}2]Cl {R = Me (12), Et (13)} have also been isolated and characterised. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Electronic Interactions in Ferrocene- and Ruthenocene-Functionalized Tetraazamacrcocyclic Ligand Complexes of FeII/III, CoII, NiII, CuII and ZnIIEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2005Peter Comba Abstract The syntheses of ferrocene- and ruthenocene-functionalized tetraazamacrocyclic ligands and their corresponding transition metal complexes are described. Reaction of N,N, -bis(2-aminoethyl)-1,3-propanediamine (2,3,2-tet) with 1,1,-diformylferrocene and 1,1,-diformylruthenocene produces the ligands fcmac and rcmac in 81,85% yield. Examination of their CuII, NiII, CoII, ZnII and FeII/III complexes by IR, UV/Vis, EPR and Mössbauer spectroscopy as well as by electrochemical studies suggests electronic communication between the two metal centers of each complex. The molecular structure of [CuII(fcmac)(FBF3)]BF4, determined by X-ray structure analysis, is reported and shows that the distance between the two metals is 4.54 Å. Stability constants, determined by potentiometric titration, indicate that the copper(II) complexes are of similar stability as those with unfunctionalized tetraazamacrocyclic ligands (e.g. cyclam = 1,4,8,11-tetraazacyclotetradecane); stability constants of cobalt(II) complexes are about 2 log units smaller, those of nickel(II) and zinc(II) complexes are reduced by more than 10 log units. This selectivity is discussed on the basis of the structural studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Diastereomeric Halfsandwich Rhenium Complexes Containing Hemilabile Phosphane LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2004Stefan Dilsky Abstract The syntheses and some typical reactions of diastereomeric rhenium complexes [CpRe(NO)(CO){P(Ph)(R)(R,)}]BF4 (R = Me, Ph; R, = 2-C6H4OMe, CH2C4H3S, CH2C4H7O) (3a,e) are described. Reduction of the carbonyl ligand with NaBH4 in THF gave the corresponding methyl complexes [CpRe(NO){P(Ph)(R)(R,)}(CH3)] (4a,e). Acid treatment of the methyl complexes leads to liberation of methane and coordination of the additional donor site of the potentially bidentate phosphane ligand. Of the chelate complexes 5a,e, those with R, = 2-C6H4OMe (5a, d) decomposed in solution at room temperature. In donor solvents, the chelate ring opens giving the stable solvated complexes [CpRe(NO){P(Ph)(R)(R,)}](solvent)]BF4 (solvent = CH3CN, THF) (6b,e, 7d). The new compounds are thus suitable starting materials for the syntheses of diastereomeric rhenium complexes [CpRe(NO){P(Ph)(R)(R,)}(L)]BF4. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] endo and exo Coordination of Indanol: Synthesis, Isolation and Structural Characterisation of [H3Ru3(endo -Indanol)(C6Me6)2(O)]+ and [H3Ru3(exo -Indanol)(C6Me6)2(O)]+ as Their Tetrafluoroborate SaltsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2004Ludovic Vieille-Petit Abstract The reaction of 2,3,4,7-tetrahydro-1H -inden-2-ol with ruthenium chloride hydrate in refluxing ethanol yields the chloro-bridged dinuclear complex [RuCl2(indanol)]2 (1). The mononuclear complex [Ru(indanol)(H2O)3]2+ (2), formed in situ from 1 in aqueous solution, reacts with the dinuclear complex [H3Ru2(C6Me6)2]+ to give a trinuclear arene-ruthenium cluster as a mixture of two isomers, the cations [H3Ru3(endo -indanol)(C6Me6)2(O)]+ (3a) and [H3Ru3(exo -indanol)(C6Me6)2(O)]+ (3b), in a 1:1 ratio. The hydroxy function of the indanol ligand is oriented towards the ,3 -oxo cap of 3a, whereas the OH group is bent away from the metal skeleton of 3b. These two isomers, which can easily be separated by silica-gel chromatography, were isolated and characterised as their tetrafluoroborate salts. The single-crystal X-ray structure analysis of [3a][BF4] shows a strong intramolecular hydrogen bond between the ,3 -oxo ligand and the hydroxyl function, which even persists in acetone solution, as demonstrated by NMR spectroscopy. On the other hand, the hydroxy function of 3b was found to be free in the solid state as well as in solution, as shown by an X-ray crystal structure analysis and by NMR spectroscopy. The catalytic activities of the water-soluble trinuclear cations 3a and 3b for the hydrogenation of benzene to give cyclohexane under biphasic conditions are considerably different, the exo isomer 3b being more active than the endo isomer 3a. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] A Study of the Electronic Spin-State Crossover in {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2004Daniel L. Reger Abstract The synthesis, structural, magnetic, and Mössbauer spectroscopic properties of {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 are reported. The single-crystal X-ray structure results indicate that at 150 K {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 has a structure which is very similar to that observed at 220 K for the trigonally distorted octahedral, high-spin {Fe[HC(3,5-Me2pz)3]2}(BF4)2 complex. Both the magnetic and Mössbauer spectroscopic results indicate that {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 is high spin between 160 and 296 K. Upon cooling, {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 exhibits a complete electronic spin-state crossover from the high-spin to the low-spin state at approximately 110 K and remains completely low spin down to 4.2 K; upon subsequent warming from 4.2 K, the transition from the low-spin to the high-spin state occurs at 148 to 150 K. {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 exhibits a rather large thermal hysteresis of 38 K in its spin-state crossover. Thus, {Fe[HC(3,4,5-Me3pz)3]2}(BF4)2 behaves differently from both {Fe[HC(3,5-Me2pz)3]2}(BF4)2, which is known to show a unique spin-state crossover of one-half of its iron(II) ions associated with a phase transition, and Fe[HB(3,4,5-Me3pz)3]2, which is known to remain high-spin even upon cooling to 1.7 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] (Pyrazole)silver(I) and -gold(I) Complexes with Strong and Weak Hydrogen-Bonding Interactions as the Basis of One- or Two-Dimensional StructuresEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2004M. Luz Gallego Abstract New AuI/AgI complexes containing one or two substituted pyrazole ligands [Au(Hpzbp2)(PPh3)](p -CH3C6H4SO3) [Hpzbp2 = 3,5-bis(4- n -butoxyphenyl)pyrazole] (1) and [M(HpzR2)2]nX [HpzR2 = Hpzbp2, M = Au, n = 1, X = p -CH3C6H4SO3 (2), NO3, (3); n = 2, X = 1,5-naphthalenedisulfonate (1,5nds) (4); HpzR2 = Hpzbp2, M = Ag, n = 1, X = BF4, (5), CF3SO3, (6); HpzR2 = HpzNO2 (3,5-dimethyl-4-nitropyrazole), M = Ag, n = 1, X = BF4, (7), CF3SO3, (8)], have been prepared and characterized. Compounds 1, 2, 5 and 8 have been proved to be useful for supramolecular assembly from their single X-ray diffraction analysis. In all cases strong hydrogen bonds maintain the cationic units bonded to their corresponding counterions. The crystal packing arrangement of 1, 2 and 5 is, however, determined by weak C,H···O/F hydrogen-bonding interactions involving the remaining O/F atoms of the counterion. By contrast, for 8 a two-dimensional layer-type polymeric network is formed by ,···, (NO2···NO2) and coordinative Ag···O interactions in which the NO2 substituent on the pyrazole is implicated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Synthesis of a Metallamacrocyclic Re(CO)3 Complex Using a Tridentate Bridging LigandEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2004Thomas Brasey Abstract The reaction of [ReBr3(CO)3][NEt4]2 with 3-hydroxy-1,2,3-benzotriazine-4(3H)-one in the presence of base gave the ionic rhenium complex [ReBr(C7H4N3O2)(CO)3][NEt4] (2) which was crystallographically characterized. A neutral metallamacrocycle 3 was obtained upon abstraction of [NEt4]Br from complex 2. This complex cocrystallizes with an unusual C3 -symmetric [Ag(,2 -benzene)3(OH2)][BF4] complex as evidenced by single-crystal X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] New Pentadentate Carboxylate-Derivatized Sulfur Ligands Affording Water Soluble Iron Complexes with [Fe(NS4)] Cores that Bind Small Molecules (CO, NO, PMe3) as Co-LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 3 2004Dieter Sellmann Abstract In the search for polydentate sulfur ligands that are able to form water-soluble iron complexes which can bind nitrogenase relevant molecules, the new pentadentate ligands pyCO2MeS4,H2 [2,6-bis[2-mercapto-3-(methoxycarbonyl)phenylthio]dimethylpyridine] (1) and pyCO2HS4,H2 [2,6-bis(2-mercapto-3-carboxyphenylthio)dimethylpyridine] (2) having NS4 donor atom sets and terminal thiolate donors have been synthesized. The starting material was CO2MeS2,H2 (2,3-dimercapto benzoic acid methyl ester) which was alkylated with 2,6-bis[(tosyloxy)methyl]pyridine. The problem of specifically achieving regioselective mono-alkylation of this 1,2-benzene-dithiol derivative was solved by carrying out the alkylation of CO2MeS2,H2 at ,78 °C in the presence of stoichiometric amounts of a base. Saponification of 1 afforded the carboxylic acid derivative. Coordination of pyCO2MeS42, to FeII in the presence of co-ligands (L = CO, PMe3) yielded the complexes [Fe(L)(pyCO2MeS4)] where L = CO (5) or PMe3 (4). Upon treatment with NOBF4, complex 5 afforded [Fe(NO)(pyCO2MeS4)]BF4 (7) which could be subsequently converted to the isolable 19 valence electron species [Fe(NO)(pyCO2MeS4)] (8) upon reduction with N2H4. In the absence of potential co-ligands, coordination of pyCO2MeS42, to FeII afforded the dinuclear complex [Fe(pyCO2MeS4)]2 (6) whilst coordination to NiII gave [Ni(pyCO2MeS4)]x (3). Solubility of these complexes in water could be achieved by replacing the CO2Me groups with CO2H substituents. The ligand pyCO2HS42, afforded the iron complexes [Fe(L)(pyCO2HS4)] [L = CO (10) and PMe3 (12)] and [Fe(NO)(pyCO2HS4)]BF4 (11). Both 10 and 12 could be reversibly deprotonated to give the corresponding water-soluble salts (NMe4)2[Fe(L)(pyCO2S4)] with L = CO {(NMe4)2 [9]} and PMe3 {(NMe4)2 [13]}. The complexes were characterized by elemental analysis, spectroscopic methods and X-ray structural determinations. The molecular structure of [Fe(PMe3)(pyCO2HS4)] (12) was found to exhibit inter- and intramolecular O,H···O and O,H···S hydrogen bonds which serve as models for proton transfer steps from external sources to the active sites of metal sulfur enzymes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Structure-Dependent Electrochemical Behavior of Thienylplatinum(II) Complexes of N,N-HeterocyclesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2004Feng Zhao Abstract trans -[Pt(MeCN)(PPh3)2(2-thienyl)]BF4 (1) serves as a convenient precursor to bifunctional mononuclear trans -[Pt(PPh3)2(,1 - N - N)(2-thienyl)]BF4 [N - N = pyrazine (2); 2-chloropyrazine, (3)] and dinuclear trans,trans -[Pt2(PPh3)4(,- N - N)(2-thienyl)2](BF4)2 [(N - N = 4,4, -bipyridine (4); 4,4, -vinylenedipyridine (5)] complexes. The nuclear selectivity is conveniently controlled by the choice of the heterocyclic ligands or spacers. Both structural types 3 and 5 were confirmed by single-crystal X-ray crystallographic analyses. Their solution identities were established by positive-ion Electrospray Mass Spectrometry (ESMS). The electroactivities of these complexes were studied by cyclic voltammetry (CV). Continuous CV scans of 4 and 5 revealed variations in the redox waves with the number of scans. While the initial oxidative scan exhibited only a broad, irreversible wave, further cycling showed the growth of two additional redox couples up to about the tenth cycle. The peak currents of these redox couples began to decay with prolonged potential cycling beyond the tenth cycle. These findings are consistent with the formation of electroactive oligomers/polymers, and this conclusion is supported by visible thin film formation on the electrodes. In contrast, the mononuclear complexes (2 and 3) do not show such behavior. The films formed were further studied by repetitive potential cycling and XPS. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] New [Ru3(CO)12]-Based Catalysts with Imidazolinium Salt, Diimine, or Bis(oxazoline) Ligands and Ruthenium Bis(oxazoline) Complex for Tandem Isomerisation/Claisen Rearrangement of Dienyl Ethers , X-ray Structure of [RuCl{(R,R)-bis(isopropyloxazoline)}(p -cymene)]BF4EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 22 2003Hamed Ben Ammar Abstract The reaction of various 1,7-dienes in the presence of the three-component catalyst A: [Ru3(CO)12]/imidazolinium salt/Cs2CO3 (1:1:2) leads to the tandem alkene isomerisation/Claisen rearrangement affording ,,,-unsaturated aldehydes. Other three component catalysts: [Ru3(CO)12]/diimine/Cs2CO3 and [Ru3(CO)12]/benzoxazoline or chiral bis(oxazoline)/Cs2CO3 offer new active catalytic systems for these tandem reactions. Two ruthenium complexes containing optically active bis(oxazoline), [RuCl{(R,R)-bis(oxazoline)}(p -cymene)]BF4, were prepared and the X-ray structure of one of them (18) was established. The combination of chiral 18/imidazolinium salt/Cs2CO3 (1:1:2) catalysed the above reaction of 1,6-dienes and the results suggest initial catalytic isomerisation followed by a thermal Claisen rearrangement. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Recoverable Phase-Transfer Catalysts with Fluorinated Anions: Generation and Reactions of Dichlorocarbene and CCl3 Anion in the Heterogeneous System KOH(s)/CHCl3/nBu4NPF6EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 10 2008Galina V. Kryshtal Abstract Tetraalkylammonium salts bearing PF6, and BF4, anions have been recognized as recoverable phase-transfer catalysts for the synthesis of 1,1-dichlorocyclopropane and ,-(trichloromethyl)carbinol derivatives from alkenes or aldehydes in the heterogeneous system KOH(s)/CHCl3. The catalysts retained their catalytic activity over several reactioncycles.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Efficient, Rhodium-Catalyzed Hydrogenation of ,-Dehydroamino Acid Esters with Chiral Monodentate Aminophosphanes Bearing Two Binaphthyl GroupsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 32 2007Luc Eberhardt Abstract All four stereoisomers of 4-{4,5-dihydro-3H -dinaphtho[2,1- c:1,,2,- e]azepin-4-yl}dinaphtho[2,1- d:1,,2,- f][1,3,2]dioxaphosphepine have been prepared from (R or S)-1,1,-binaphthyl-2,2,-diyl chlorophosphite and the appropriate dinaphtho-azepine. When reacted with [Rh(1,5-cyclooctadiene)2]BF4, highly active catalysts for the hydrogenation of ,-dehydroamino acid esters were obtained. The highest enantioselectivities (up to 99,% ee) were achieved with the phosphoramidites having two chiral binaphthyl groups with opposite configurations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Intramolecular Heck Reactions for the Synthesis of the Novel Antibiotic Mensacarcin: Investigation of Catalytic, Electronic and Conjugative Effects in the Preparation of the Hexahydroanthracene CoreEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 9 2005Lutz F. Tietze Abstract The intramolecular Heck reaction of the three complex diphenyl substrates rac - 2, 5 and rac - 6, containing substituents with different electronic and conjugative properties, were examined. The Pd compounds [Pd2(dba)3]/[(tBu)3PH]BF4, [Pd2(OAc)2{P(o -Tol)3}2] (4), [PdCl2(PPh3)2] and Pd(OAc)2 were used as catalysts. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Novel Heteroleptic CuI Complexes with Tunable Emission Color for Efficient Phosphorescent Light-Emitting Diodes,ADVANCED FUNCTIONAL MATERIALS, Issue 15 2007Q. Zhang Abstract A series of orange-red to red phosphorescent heteroleptic CuI complexes (the first ligand: 2,2,-biquinoline (bq), 4,4,-diphenyl-2,2,-biquinoline (dpbq) or 3,3,-methylen-4,4,-diphenyl-2,2,-biquinoline (mdpbq); the second ligand: triphenylphosphine or bis[2-(diphenylphosphino)phenyl]ether (DPEphos)) have been synthesized and fully characterized. With highly rigid bulky biquinoline-type ligands, complexes [Cu(mdpbq)(PPh3)2](BF4) and [Cu(mdpbq)(DPEphos)](BF4) emit efficiently in 20,wt,% PMMA films with photoluminescence quantum yield of 0.56 and 0.43 and emission maximum of 606,nm and 617,nm, respectively. By doping these complexes in poly(vinyl carbazole) (PVK) or N -(4-(carbazol-9-yl)phenyl)-3,6-bis(carbazol-9-yl) carbazole (TCCz), phosphorescent organic light-emitting diodes (OLEDs) were fabricated with various device structures. The complex [Cu(mdpbq)(DPEphos)](BF4) exhibits the best device performance. With the device structure of ITO/PEDOT/TCCz:[Cu(mdpbq)(DPEphos)](BF4) (15,wt,%)/TPBI/LiF/Al (III), a current efficiency up to 6.4,cd,A,1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.61, 0.39) has been realized. To our best knowledge, this is the first report of efficient mononuclear CuI complexes with red emission. [source] | ||||||||||||||||||||||||||||