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Organometallic Chemistry (organometallic + chemistry)
Selected AbstractsPreface: XIVth FECHEM Conference on Organometallic Chemistry, 2,7 September, 2001, Gdansk, PolandAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2002Article first published online: 23 JUL 200 No abstract is available for this article. [source] T. Gunji, H. Yamamoto, T. Hanaoka, K. Bandoh-Kitmura and Y. Abe, ,Preparation of polyzirconoxane from zirconium octahydrate and ethylene glycol as a precursor for zirconia ceramics'.APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2001Applied Organometallic Chemistry 2000; 14(2):11 The original article to which this Erratum refers was published in Applied Organometallic Chemistry 2000; 14(2):119,126. In the Table of Contents for the February 2000 issue of Applied Organometallic Chemistry, Volume 14 Number 2, the authors of the paper appearing on page 119, ,Preparation of polyzirconoxane from zirconium octahydrate and ethylene glycol as a precursor for zirconia ceramics', should have been listed as T. Gunji, H. Yamamoto, T. Hanaoka, K. Bandoh-Kitmura and Y. Abe. [source] Regioselective Carbon,Carbon Bond Formation in Proteins with Palladium Catalysis; New Protein Chemistry by Organometallic ChemistryCHEMBIOCHEM, Issue 1 2006Koichiro Kodama Abstract Palladium-catalyzed reactions have contributed to the advancement of many areas of organic chemistry, in particular, the synthesis of organic compounds such as natural products and polymeric materials. In this study, we have used a Mizoroki,Heck reaction for site-specific carbon,carbon bond formation in the Ras protein. This was performed by the following two steps: 1) the His6 -fused Ras protein containing 4-iodo- L -phenylalanine at position 32 (iF32-Ras-His) was prepared by genetic engineering and 2) the aryl iodide group on the iF32-Ras-His was coupled with vinylated biotin in the presence of a palladium catalyst. The biotinylation was confirmed by Western blotting and liquid chromatography,mass spectrometry (LC-MS). The regioselectivity of the Mizoroki,Heck reaction was furthermore confirmed by LC-MS/MS analysis. However, in addition to the biotinylated product (bF32-Ras-His), a dehalogenated product (F32-Ras-His) was detected by LC-MS/MS. This dehalogenation resulted from the undesired termination of the Mizoroki,Heck reaction due to steric and electrostatic hindrance around residue 32. The biotinylated Ras showed binding activity for the Ras-binding domain as its downstream target, Raf-1, with no sign of decomposition. This study is the first report of an application of organometallic chemistry in protein chemistry. [source] Medicinal Organometallic Chemistry: Designing Metal Arene Complexes as Anticancer AgentsCHEMISTRY - AN ASIAN JOURNAL, Issue 11 2008Abstract The field of medicinal inorganic chemistry is rapidly advancing. In particular organometallic complexes have much potential as therapeutic and diagnostic agents. The carbon-bound and other ligands allow the thermodynamic and kinetic reactivity of the metal ion to be controlled and also provide a scaffold for functionalization. The establishment of structure,activity relationships and elucidation of the speciation of complexes under conditions relevant to drug testing and formulation are crucial for the further development of promising medicinal applications of organometallic complexes. Specific examples involving the design of ruthenium and osmium arene complexes as anticancer agents are discussed. [source] Organometallic chemistry on rhodaheteroborane clusters: reactions with bidentate phosphines and organotransition metal reagents,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 6-7 2003Oleg Volkov Abstract This article reviews our recent work on the reactions of the rhodaheteroboranes [8,8-(PPh3)2 - nido -8,7-RhSB9H10] (1) and [9,9-(PPh3)2 - nido -9,7,8-RhC2B8H11] (2), and their derivatives, with the bidentate phosphines, dppe [(CH2)2(PPh2)2], dppp [(CH2)3(PPh2)2], and dppm [CH2(PPh2)2], and also with organotransition metal reagents. Simple substitution of the two PPh3 ligands by a single bidentate phosphine takes place when a 1 : 1 molar ratio of base (dppe or dppp) to rhodathiaborane (1) is used. However, in the presence of an excess of dppe or dppp, products containing 1 or 2 mol of base are formed. These products include a bidentate ligand on the metal and a monodentate ligand on the cage. The displaced hydrogen atom from the cage has moved to the metal center. These bis(ligand) species are unstable with respect to the loss of dihydrogen, affording closo -11 vertex clusters with a pendent phosphine ligand on the cage. In concentrated solutions, the pendent phosphine attacks another cage to afford linked clusters. Under both sets of conditions, when dppm is used, only one product is observed. This species has two dppm ligands coordinated to the metal: one in a unidentate mode and the other bidentate. A similar product is obtained in the reaction of 2 with dppm, although the arrangement of the ligands on the metal in the product is different. Ligand exchange experiments on the dppm,thiaborane system lead to results that provide keys to the reaction pathways in some of these processes. The bis(dppm) derivatives of 1 and 2 are amenable to further derivatization. A second metal may be added, either as an exo -polyhedral atom in a nido cluster in which the metal is part of a bidentate ligand, in the case of 1 and 2, or in a closo cluster derivative of 1 in which the metal is bonded to a dangling PPh2 moiety. Thus, it was possible to add the metals iridium, rhodium or ruthenium to the cluster, in the case of 1 and ruthenium in the case of 2. However, the reaction of more electrophilic organotransition metal reagents, such as Wilkinson's catalyst, with the dppm derivative of 1 affords species resulting from removal of ligand rather than incorporation of metal, and the products shed light on the rearrangement processes in these systems. Copyright © 2003 John Wiley & Sons, Ltd. [source] An Unusual Anion,, Interaction in an ;rido Organometallic Assembly: Synthesis, First Crystal Structure, and Computational StudyEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2009Jamal Moussa Abstract The organometallic assembly [Cp*Ir(,6 -C6H2O4)(BF2)2(CF3SO3)][Cp*Ir(,-Cl)3IrCp*] (3) was prepared from [Cp*Ir(solvent)3][OTf]2 (2) and 1,2,4,5 tetrahydroxybenzene (THB, 1) in acetone, in the presence of an excess amount of BF3·2H2O. Assembly 3 was fully characterized by multinuclear NMR spectroscopy. Remarkably, the X-ray molecular structure of 3 shows that an anion,, interaction occurs between the neutral component Cp*Ir(,6 -C6H2O4)(BF2)2 of the assembly and the CF3SO3 anion of the cationic species [Cp*Ir(,-Cl)3IrCp*]. Computational analysis was carried out on 3 to unravel the nature of this noncovalent interaction. Such an example could serve as a model to explain the important role of anions in organometallic chemistry and asymmetric catalysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] The Chemistry of Technetium,Water Complexes within the Manganese Triad: Challenges and PerspectivesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2009Roger Alberto Abstract The chemistry of technetium is essentially driven by radiopharmaceutical applications. These comprise the syntheses of novel complexes but, moreover, the combination of targeting biomolecules with metal complexes. Aqua ions are especially convenient for facilitatating the introduction of metal cations into biomolecules, but are nonexistent for Tc and Re in the Mn triad. This microreview will discuss the chemistry of those Tc complexes that contain H2O as ligands. Special attention will be payed to organometallic aqua ions, i.e. complexes that are typically organometallic with water as ligand. Of particular interest is the coordination chemistry of [M(OH2)3(CO)3]+ (M = Mn, Tc, Re) complexes in water since it is the origin of the widely applied radiopharmaceutical research with 99mTc and 188Re. The chemistry of organometallic aqua ions is not confined to Werner-type ligands, hence, a further emphasis will be placed on pure organometallic chemistry in water.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Facile Access to Optically Active Ferrocenyl Derivatives with Direct Substitution of the Hydroxy Group Catalyzed by Indium TribromideEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2007Paola Vicennati Abstract Ferrocene derivatives have found many different uses and applications in organometallic chemistry, material chemistry, and catalysis. We have shown that using a catalytic amount (5,10 mol-%) of commercially available indium tribromide, at room temperature, many carbon nucleophiles, such as indoles, allylsilane, enolsilane, silyl ketene acetal, diketone, and trimethylsilylcyanide, smoothly react with different optically active ferrocenyl alcohol derivatives to afford the desired products in high yield, with retention of configuration. Also, many different N-nucleophiles (azide, carbamates) and O-nucleophiles (alcohols) react as well, again with retention of configuration. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Strategies to Immobilize Well-Defined Olefin Metathesis Catalysts: Supported Homogeneous Catalysis vs.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2007Surface Organometallic Chemistry Abstract This review is mainly devoted to a description of the strategies that have been implemented to develop well-defined olefin metathesis catalysts immobilized on solid supports. Two main approaches have been investigated involving supported homogenous catalysts or heterogeneous catalysts prepared by surface organometallic chemistry. Advantages, limitations and possible developments of these systems are discussed. [source] gem -Dimethylcyclopropanation of dibenzylideneacetone using triisopropyl sulfoxonium tetrafluoroborateACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Michael G. Edwards The reaction between dibenzylideneacetone (dba) and triisopropyl sulfoxonium tetrafluoroborate has been reinvestigated. The stereochemistry of the major diasteromeric bis(gem -dimethylcyclopropane) adduct has now been assigned as [(1RS,3RS)-2,2-dimethyl-3-phenylcyclopropyl][(1SR,3SR)-2,2-dimethyl-3-phenylcyclopropyl]methanone, C23H26O, by X-ray crystallographic studies on a twinned crystal. The asymmetric unit contains two molecules of the adduct, the conformations of which differ in the orientation of the phenyl ring relative to the adjacent cyclopropanated double bond. The carbonyl groups of each adduct are aligned approximately along the a axis and in opposite directions to each other. The molecules pack to give a sinusoidal pattern along the b axis. This is the first acyclic bis(dimethylcyclopropyl) ketone for which an X-ray crystal structure determination has been reported, and is also the first bis-cyclopropanated dba analogue. The knowledge that the major diastereomer has the meso structure (and therefore the confirmation that the minor isomer is the racemate) will prove invaluable in future studies to utilize bis(dimethylcyclopropyl) ketones as reagents, in rearrangement processes, and as potential ligands and ligand precursors in organometallic chemistry. [source] Efficient fuel cell catalysts emerging from organometallic chemistryAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2010Helmut Bönnemann Abstract During the last few decades organometallic methodologies have generated a number of highly effective electrocatalyst systems based on mono- and bimetallic nanosparticles having controlled size, composition and structure. In this microreview we summarize our results in fuel cell catalyst preparation applying triorganohydroborate chemistry, ,reductive particle stabilization' using organoaluminum compounds, and the controlled decomposition of organometallic complexes. The advantages of organometallic catalyst preparation pathways are exemplified with RuPt nanoparticles@C as promising anode catalysts to be used in direct methanol oxidation fuel cells (DMFC) or in polymer electrolyte fuel cells (PEMFC) running with CO-contaminated H2 as the feed. Recent findings with highly efficient PtCo3@C fuel cell catalysts applied for the oxygen reduction reaction (ORR) and with the effect of Se-doping on Ru@C ORR catalysts clearly demonstrate the benefits of organometallic catalyst synthesis. Copyright © 2010 John Wiley & Sons, Ltd. [source] A review,How nanoparticles emerged from organometallic chemistryAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2004Dedicated to Professor Helmut Bönnemann on the occasion of his 65th birthday First page of article [source] Regioselective Carbon,Carbon Bond Formation in Proteins with Palladium Catalysis; New Protein Chemistry by Organometallic ChemistryCHEMBIOCHEM, Issue 1 2006Koichiro Kodama Abstract Palladium-catalyzed reactions have contributed to the advancement of many areas of organic chemistry, in particular, the synthesis of organic compounds such as natural products and polymeric materials. In this study, we have used a Mizoroki,Heck reaction for site-specific carbon,carbon bond formation in the Ras protein. This was performed by the following two steps: 1) the His6 -fused Ras protein containing 4-iodo- L -phenylalanine at position 32 (iF32-Ras-His) was prepared by genetic engineering and 2) the aryl iodide group on the iF32-Ras-His was coupled with vinylated biotin in the presence of a palladium catalyst. The biotinylation was confirmed by Western blotting and liquid chromatography,mass spectrometry (LC-MS). The regioselectivity of the Mizoroki,Heck reaction was furthermore confirmed by LC-MS/MS analysis. However, in addition to the biotinylated product (bF32-Ras-His), a dehalogenated product (F32-Ras-His) was detected by LC-MS/MS. This dehalogenation resulted from the undesired termination of the Mizoroki,Heck reaction due to steric and electrostatic hindrance around residue 32. The biotinylated Ras showed binding activity for the Ras-binding domain as its downstream target, Raf-1, with no sign of decomposition. This study is the first report of an application of organometallic chemistry in protein chemistry. [source] Metal-Mediated Formation of Carbon,Halogen BondsCHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2008Arkadi Vigalok Prof. Dr. Abstract Organic halides represent basic starting materials for numerous metal-catalyzed organic transformations. Generally, the carbon,halogen is broken in the first step, that is, an oxidative addition reaction, of the catalytic cycle. On the other hand, very little is known about the reverse reaction, carbon,halogen reductive elimination from a transition-metal center. In this Concept article, we describe the examples of C(sp3)halide and C(sp2)halide reductive-elimination reactions which demonstrate that this type of reactivity can be quite common in organometallic chemistry. Although the thermodynamic driving force for the formation of carbon,halogen bonds is relatively small, the kinetic barrier for these reactions can also be low. Thus, Chalide reductive elimination can compete favorably with the more established organic transformations, such as CC reductive elimination. [source] | |||||||||||||||||||