212 results match your criteria Organometallics [Journal]


Demystifying CpTi(H)Cl and its Enigmatic Role in the Reactions of Epoxides with CpTiCl.

Organometallics 2018 Dec 30;37(24):4801-4809. Epub 2018 Nov 30.

Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA.

The role of CpTi(H)Cl in the reactions of CpTiCl with trisubstituted epoxides has been investigated in a combined experimental and computational study. Although CpTi(H)Cl has generally been regarded as a robust species, its decomposition to CpTiCl and molecular hydrogen was found to be exothermic (ΔG = -11 kcal/mol when the effects of THF solvation are considered). In laboratory studies, CpTi(H)Cl was generated using the reaction of 1,2-epoxy-1-methylcyclohexane with CpTiCl as a model. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6363350PMC
December 2018

Synthesis and Complexation of a Free Germanide Bearing a Tridentate N-Heterocyclic Substituent.

Organometallics 2019 Jan 9;38(2):231-239. Epub 2019 Jan 9.

Department of Chemistry, Debye Institute for Nanomaterials Science Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.

The tris-N-heterocycle germanide (tmim)Ge () (tmimH = tris(3-methylindol-2-yl)methane) was synthesized by nucleophilic substitution for the tmim trianion on GeCl·dioxane. In combination with the previously reported (tmim)Si and (tmim)P analogues, it provides a convenient model for investigating the influence of the central atom on the properties of isoelectronic ligands. Complexation of the germanide (tmim)Ge to CuCl resulted in the dimeric chloro cuprate [(tmim)GeCu(μ-Cl)], which is prone to dissociation in MeCN to form the neutral, solvated germylcopper (tmim)GeCu(NCMe). Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00630DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6354728PMC
January 2019

Synthesis of High-Oxidation-State Mo═CHX Complexes, Where X = Cl, CF, Phosphonium, CN.

Organometallics 2018 Jun 21;37(11):1641-1644. Epub 2018 May 21.

Department of Chemistry 6-331, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.

Reactions between -XCH=CHX where X = Cl, CF, or CN and Mo(N--Bu)(CH--Bu)(OHIPT)Cl(PPhMe) (OHIPT = O-2,6-(2,4,6--PrCH)CH) produce Mo(N--Bu)(CHX)(OHIPT)Cl(PPhMe) complexes. Addition of 2,2'-bipyridyl (Bipy) yields Mo(N--Bu)(CHX)(OHIPT)Cl(Bipy) complexes, which could be isolated and structurally characterized. The reaction between Mo(N--Bu)(CH--Bu)(OHMT)Cl(PPhMe) (OHMT = O-2,6-(2,4,6-MeCH)CH) and -ClCH=CHCl in the presence of Bipy produces a mixture that contains both Mo(N--Bu)(CHCl)(OHMT)Cl(PPhMe) and Mo(N--Bu)(CHCl)(OHMT)Cl(Bipy), but the relatively insoluble product that crystallizes from toluene- is the phosphoniomethylidene complex, [Mo(N--Bu)(CHPPhMe)(OHMT)(Cl)(Bipy)]Cl. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00168DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6332497PMC

Phosphino-Triazole Ligands for Palladium-Catalyzed Cross-Coupling.

Organometallics 2018 Nov 17;37(22):4224-4241. Epub 2018 Oct 17.

School of Chemistry and X-ray Crystallography Facility, School of Chemistry, University of Birmingham, Edgbaston, Birmingham, West Midlands B15 2TT, United Kingdom.

Twelve 1,5-disubtituted and fourteen 5-substituted 1,2,3-triazole derivatives bearing diaryl or dialkyl phosphines at the 5-position were synthesized and used as ligands for palladium-catalyzed Suzuki-Miyaura cross-coupling reactions. Bulky substrates were tested, and lead-like product formation was demonstrated. The online tool SambVca2. Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.8b00539
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http://dx.doi.org/10.1021/acs.organomet.8b00539DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6265957PMC
November 2018
7 Reads

Combined Effects of Backbone and N-Substituents on Structure, Bonding, and Reactivity of Alkylated Iron(II)-NHCs.

Organometallics 2018 Sep 6;37(18):3093-3101. Epub 2018 Sep 6.

Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.

Iron and -heterocyclic carbenes (NHCs) have proven to be a successful pair in catalysis, with reactivity and selectivity being highly dependent on the nature of the NHC ligand backbone saturation and -substituents. Four (NHC)Fe(1,3-dioxan-2-ylethyl) complexes have been isolated and spectroscopically characterized to correlate their reactivity to steric effects of the NHC from the backbone saturation and -substituents. Only in the extreme case of SIPr where NHC backbone and -substituent steric effects are the largest is there a major structural perturbation observed crystallographically. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6241324PMC
September 2018

Rhodium(III) and Iridium(III) Complexes of a NHC-Based Macrocycle: Persistent Weak Agostic Interactions and Reactions with Dihydrogen.

Organometallics 2018 Nov 9;37(21):3963-3971. Epub 2018 Oct 9.

Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, U.K.

The synthesis and characterization of five-coordinate rhodium(III) and iridium(III) 2,2'-biphenyl complexes [M(CNC-12)(biph)][BAr] (M = Rh (), Ir ()), featuring the macrocyclic lutidine- and NHC-based pincer ligand CNC-12 are reported. In the solid state these complexes are notable for the adoption of weak ε-agostic interactions that are characterized by ···H- contacts of ca. 3. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00595DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6234485PMC
November 2018
5 Reads

Synthesis of N-Heterocycle Substituted Silyl Ligands within the Coordination Sphere of Iron.

Organometallics 2018 Sep 10;37(18):3024-3034. Epub 2018 Sep 10.

Department of Chemistry, Debye Institute for Nanomaterials Science Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.

N-Heterocycle-substituted silyl iron complexes have been synthesized by nucleophilic substitution at trichlorosilyl ligands bound to iron. The homoleptic (tripyrrolyl)- and tris(3-methylindolyl)silyl groups were accessed from (ClSi)CpFe(CO) (ClSiFp) by substitution of chloride with pyrrolide or 3-methylindolide, respectively. Analogously, nucleophilic substitution of Cl with pyrrolide on the anionic Fe(0) synthon ClSiFe(CO) generates the (tripyrrolyl)silyl ligand, bound to the iron tetracarbonyl fragment. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00399DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6158677PMC
September 2018

Bench-Stable Nickel Precatalysts with Heck-type Activation.

Organometallics 2018 Aug 9;37(16):2716-2722. Epub 2018 Aug 9.

Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.

Herein, we report the synthesis and characterization of a new class of air- and moisture-stable phosphine-containing nickel(II) precatalysts, which activate through a Heck-type mechanism. The activities of the precatalysts are demonstrated with a carbonyl-ene coupling reaction. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6113681PMC

Transfer Hydrogenation and Antiproliferative Activity of Tethered Half-Sandwich Organoruthenium Catalysts.

Organometallics 2018 May 23;37(10):1555-1566. Epub 2018 Apr 23.

Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, U.K.

We report the synthesis and characterization of four neutral organometallic tethered complexes, [Ru(η-Ph(CH)-ethylenediamine--R)Cl], where R = methanesulfonyl (Ms, ), toluenesulfonyl (Ts, ), 4-trifluoromethylbenzenesulfonyl (Tf, ), and 4-nitrobenzenesulfonyl (Nb, ), including their X-ray crystal structures. These complexes exhibit moderate antiproliferative activity toward human ovarian, lung, hepatocellular, and breast cancer cell lines. Complex in particular exhibits a low cross-resistance with cisplatin. Read More

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http://dx.doi.org/10.1021/acs.organomet.8b00132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5989272PMC
May 2018
11 Reads

DFT Investigation of Suzuki-Miyaura Reactions with Aryl Sulfamates Using a Dialkylbiarylphosphine-Ligated Palladium Catalyst.

Organometallics 2017 Sep 13;36(18):3664-3675. Epub 2017 Sep 13.

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, Oslo 0315, Norway.

Aryl sulfamates are valuable electrophiles for cross-coupling reactions because they can easily be synthesized from phenols and can act as directing groups for C-H bond functionalization prior to cross-coupling. Recently, it was demonstrated that (1-Bu-Indenyl)Pd(XPhos)Cl (XPhos = 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl) is a highly active precatalyst for room-temperature Suzuki-Miyaura couplings of a variety of aryl sulfamates. Herein, we report an in-depth computational investigation into the mechanism of Suzuki-Miyaura reactions with aryl sulfamates using an XPhos-ligated palladium catalyst. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5967261PMC
September 2017
2 Reads

Half-Sandwich Arene Ruthenium(II) and Osmium(II) Thiosemicarbazone Complexes: Solution Behavior and Antiproliferative Activity.

Organometallics 2018 Mar 20;37(6):891-899. Epub 2018 Feb 20.

Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale and CIRCMSB (Consorzio Interuniversitario di Ricerca in Chimica dei Metalli nei Sistemi Biologici), University of Parma, Parco Area delle Scienze 11/A, 43124 Parma, Italy.

We report the synthesis, characterization, and antiproliferative activity of organo-osmium(II) and organo-ruthenium(II) half-sandwich complexes [(η--cym)Os(L)Cl]Cl ( and ) and [(η--cym)Ru(L)Cl]Cl ( and ), where L = -(2-hydroxy)-3-methoxybenzylidenethiosemicarbazide () or -(2,3-dihydroxybenzylidene)-3-phenylthiosemicarbazide (), respectively. X-ray crystallography showed that all four complexes possess half-sandwich pseudo-octahedral "three-legged piano-stool" structures, with a neutral N,S-chelating thiosemicarbazone ligand and a terminal chloride occupying three coordination positions. In methanol, / isomerization of the coordinated thiosemicarbazone ligand was observed, while in an aprotic solvent like acetone, partial dissociation of the ligand occurs, reaching complete displacement in a more coordinating solvent like DMSO. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00875DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5908187PMC
March 2018
4 Reads

Role of σ,π-Digold(I) Alkyne Complexes in Reactions of Enynes.

Organometallics 2018 Mar 19;37(5):781-786. Epub 2017 Dec 19.

Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain.

Gold(I) acetylide and σ,π-digold(I) alkyne complexes derived from one prototypical 1,6-enyne and from 7-ethynyl-1,3,5-cycloheptatriene have been prepared and structurally characterized. Their possible role in gold(I)-catalyzed cycloisomerizations has been studied by experiment and by DFT calculations. Gold(I) acetylides are totally unproductive complexes in the absence of Brønsted acids. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00668DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5850095PMC
March 2018
2 Reads

Dinuclear Nickel Complexes of Thiolate-Functionalized Carbene Ligands and Their Electrochemical Properties.

Organometallics 2018 Mar 4;37(5):740-747. Epub 2017 Oct 4.

Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.

Four dimeric nickel(II) complexes [NiCl(BnCS)] [], [NiCl(BnCS)] [], [Ni(PyCS)]Br []Br, and [Ni(PyCS)]Br []Br of four different thiolate-functionalized N-heterocyclic carbene (NHC) ligands were synthesized, and their structures have been determined by single-crystal X-ray crystallography. The four ligands differ by the alkyl chain length between the thiolate group and the benzimidazole nitrogen (two -C- or three -C- carbon atoms) and the second functionality at the NHC being a benzyl (Bn) or a pyridylmethyl (Py) group. The nickel(II) ions are coordinated to the NHC carbon atom and the pendent thiolate group, which bridges to the second nickel(II) ion creating the dinuclear structure. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00576DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5850092PMC
March 2018
4 Reads

Iridium and Ruthenium Complexes of -Heterocyclic Carbene- and Pyridinol-Derived Chelates as Catalysts for Aqueous Carbon Dioxide Hydrogenation and Formic Acid Dehydrogenation: The Role of the Alkali Metal.

Organometallics 2017 Mar 3;36(6):1091-1106. Epub 2017 Mar 3.

Department of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, Alabama 35487-0336, United States.

Hydrogenation reactions can be used to store energy in chemical bonds, and if these reactions are reversible, that energy can be released on demand. Some of the most effective transition metal catalysts for CO hydrogenation have featured pyridin-2-ol-based ligands (e.g. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00806DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5840859PMC
March 2017
34 Reads

N-Heterocycle-Ligated Borocations as Highly Tunable Carbon Lewis Acids.

Organometallics 2017 Dec 8;36(24):4952-4960. Epub 2017 Dec 8.

School of Chemistry, The University of Manchester, Manchester M13 9PL, United Kingdom.

The relative (to BEt) hydride ion affinity (HIA) of a series of acridine borenium salts has been calculated, with some HIAs found to be similar to that for [PhC]. The HIA at the acridine C9 position is controlled by both acridine and the boron substituents, the latter presumably affecting the strength of the B=N bond in the acridane-BY products from hydride transfer. Through a range of hydride abstraction benchmarking reactions against organic hydride donors the experimental HIA of [Facr-BCat] (cat = catechol, Facr = 1,2,3,4,7-pentafluoroacridine) has been confirmed to be extremely high and closely comparable to that of [PhC]. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5803673PMC
December 2017
2 Reads

Ruthenium PNN(O) Complexes: Cooperative Reactivity and Application as Catalysts for Acceptorless Dehydrogenative Coupling Reactions.

Organometallics 2017 Apr 6;36(8):1541-1549. Epub 2017 Apr 6.

Homogeneous, Supramolecular & Bio-inspired Catalysis, van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.

The novel tridentate PNN pincer ligand features a reactive 2-hydroxypyridine functionality as well as a bipyridyl-methylphosphine skeleton for meridional coordination. This proton-responsive ligand coordinates in a straightforward manner to RuCl(CO)(H)(PPh) to generate complex . The methoxy-protected analogue was also coordinated to Ru(II) for comparison. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00111DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770139PMC
April 2017
5 Reads

Halide Control of Coordination versus -Cyclometalation and Stereospecific Phenyl Ring Deuteration of Osmium(II) -Cymene Phenylazobenzothiazole Complexes.

Organometallics 2017 Nov 9;36(22):4367-4375. Epub 2017 Nov 9.

Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, U.K.

We report the synthesis of halido Os(II) -cymene complexes bearing bidentate chelating phenylazobenzothiazole (AZBTZ) ligands. Unlike the analogous phenylazopyridine (AZPY) complexes, AZBTZ-NMe is capable of both -coordination to Os(II) and cyclometalation to form -coordinated species. -Coordination occurs via an azo nitrogen and an ortho carbon on the aniline ring, as identified by H NMR and X-ray crystallography of [Os(-cym)(-AZBTZ-NMe)Cl]PF (), [Os(-cym)(-AZBTZ-NMe)Br]PF (), [Os(-cym)(-AZBTZ-NMe)Br] (), and [Os(-cym)(-AZBTZ-NMe)I] (). Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00501DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5726741PMC
November 2017
10 Reads

Mild spCarbon-Oxygen Bond Activation by an Isolable Ruthenium(II) Bis(dinitrogen) Complex: Experiment and Theory.

Organometallics 2017 Sep 14;36(18):3654-3663. Epub 2017 Sep 14.

Department of Chemistry, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom.

The isolable ruthenium(II) bis(dinitrogen) complex [Ru(H)(N)(PCy)] () reacts with aryl ethers (Ar-OR, R = Me and Ar) containing a ketone directing group to effect spC-O bond activation at temperatures below 40 °C. DFT studies support a low-energy Ru(II)/Ru(IV) pathway for C-O bond activation: oxidative addition of the C-O bond to Ru(II) occurs in an asynchronous manner with Ru-C bond formation preceding C-O bond breaking. Alternative pathways based on a Ru(0)/Ru(II) couple are competitive but less accessible due to the high energy of the Ru(0) precursors. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00632DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5684690PMC
September 2017
11 Reads

Antibacterial Properties of Metallocenyl-7-ADCA Derivatives and Structure in Complex with CTX-M -Lactamase.

Organometallics 2017 May 1;36(9):1673-1676. Epub 2017 Feb 1.

Department of Molecular Medicine, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Blvd., Tampa, Florida 33612, United States.

A series of six novel metallocenyl-7-ADCA (metallocenyl = ferrocenyl or ruthenocenyl; 7-ADCA = 7-aminodesacetoxycephalosporanic acid) conjugates were synthesized and their antibacterial properties evaluated by biochemical and microbiological assays. The ruthenocene derivatives showed a higher level of inhibition of DD-carboxypeptidase 64-575, a Penicillin Binding Protein (PBP), than the ferrocene derivatives and the reference compound penicillin G. Protein X-ray crystallographic analysis revealed a covalent acyl-enzyme complex of a ruthenocenyl compound with CTX-M β-lactamase E166A mutant, corresponding to a similar complex with PBPs responsible for the bactericidal activities of these compounds. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00888DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5642929PMC
May 2017
16 Reads

Interplay between Terminal and Bridging Diiron Hydrides in Neutral and Oxidized States.

Organometallics 2017 Jun 18;36(11):2245-2253. Epub 2017 May 18.

School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 South Goodwin Avenue, Urbana, Illinois 61801, United States.

This study describes the structural, spectroscopic, and electrochemical properties of electronically unsymmetrical diiron hydrides. The terminal hydride Cp*Fe(pdt)Fe(dppe)(CO)H ([(-H)], Cp* = MeC, pdt = CH(CHS), dppe = PhPCHPPh) was prepared by hydride reduction of [Cp*Fe(pdt)Fe(dppe)(CO)(NCMe)]. As established by X-ray crystallography, [(-H)] features a terminal hydride ligand. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5538148PMC
June 2017
21 Reads

Characterization of a Borane Complex of a Diiron Dithiolate: Model for an Elusive Dihydrogen Adduct.

Organometallics 2017 Jun 16;36(11):2054-2057. Epub 2017 May 16.

Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126-Milan, Italy.

The azadithiolate complex Fe[(SCH)NMe](CO) reacts with borane to give an initial 1:1 adduct, which spontaneously decarbonylates to give Fe[(SCH)NMeBH](CO). Featuring a Fe-H-B three-center, two-electron interaction, the pentacarbonyl complex is a structural model for H complexes invoked in the [FeFe]-hydrogenases. The pentacarbonyl compound is a " complex", where a B-H bond serves as a ligand for iron. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5538135PMC
June 2017
3 Reads

Generation of Ti Alkyne Trimerization Catalysts in the Absence of Strong Metal Reductants.

Organometallics 2017 Apr 29;36(7):1383-1390. Epub 2017 Mar 29.

Department of Chemistry, University of Minnesota-Twin Cities, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States.

Low-valent Ti species have typically been synthesized by the reaction of Ti halides with strong metal reductants. Herein we report that Ti species can be generated simply by reacting Ti imido complexes with 2 equiv of alkyne, yielding a metallacycle that can reductively eliminate pyrrole while liberating Ti. In order to probe the generality of this process, Ti-catalyzed alkyne trimerization reactions were carried out with a diverse range of Ti precatalysts. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00096DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5497852PMC
April 2017
10 Reads

Transition-Metal-Free Formation of C-E Bonds (E = C, N, O, S) and Formation of C-M Bonds (M = Mn, Mo) from -Heterocyclic Carbene Mediated Fluoroalkene C-F Bond Activation.

Organometallics 2017 Feb 6;36(4):849-857. Epub 2017 Feb 6.

Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.

Herein, a recently reported polyfluoroalkenyl imidazolium salt is shown to react with nitrogen-, oxygen- and sulfur-based nucleophiles at the C position in a stereoselective and regioselective fashion, without the use of a transition metal. In contrast, reactivity with 1-methylimidazole demonstrates net substitution at C . This product reacts quantitatively with water, affording clean transformation of a difluoromethylene group to give an ,-unsaturated trifluoromethyl ketone. Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.6b00908
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http://dx.doi.org/10.1021/acs.organomet.6b00908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5488806PMC
February 2017
13 Reads

Tuning the Si-N Interaction in Metalated Oligosilanylsilatranes.

Organometallics 2017 Apr 21;36(7):1365-1371. Epub 2017 Mar 21.

Institut für Anorganische Chemie, Technische Universität Graz, Stremayrgasse 9, 8010 Graz, Austria.

Most known silatrane chemistry is concerned with examples where the attached silatrane substituent atom is that of an element more electronegative than silicon. The current study features silylated silatranes with a range of electropositive elements attached to the silyl group. The resulting compounds show different degrees of electron density on the silatrane-substituted silicon atom. Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.7b00084
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http://dx.doi.org/10.1021/acs.organomet.7b00084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5388899PMC
April 2017
6 Reads

Formation of Gold(III) Alkyls from Gold Alkoxide Complexes.

Organometallics 2017 Apr 27;36(7):1358-1364. Epub 2017 Mar 27.

School of Chemistry, University of East Anglia, Norwich NR4 7TJ, U.K.

The gold(III) methoxide complex (CNC)AuOMe () reacts with tris(-tolyl)phosphine in benzene at room temperature under O abstraction to give the methylgold product (CNC)AuMe () together with O=P(-tol) ((CNC) = [2,6-(CH Bu-4)pyridine]). Calculations show that this reaction is energetically favorable (Δ = -32.3 kcal mol). Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5388904PMC
April 2017
9 Reads

Iminophosphanes: Synthesis, Rhodium Complexes, and Ruthenium(II)-Catalyzed Hydration of Nitriles.

Organometallics 2017 Mar 16;36(5):1079-1090. Epub 2017 Feb 16.

Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands; Department of Chemistry, University of Johannesburg, Oakland Park 2006, South Africa.

Highly stable iminophosphanes, obtained from alkylating nitriles and reaction of the resulting nitrilium ions with secondary phosphanes, were explored as tunable P-monodentate and 1,3-P,N bidentate ligands in rhodium complexes. X-ray crystal structures are reported for both κ and κ complexes with the counterion in one of them being an unusual anionic coordination polymer of silver triflate. The iminophosphane-based ruthenium(II)-catalyzed hydration of benzonitrile in 1,2-dimethoxyethane (180 °C, 3 h) and water (100 °C, 24 h) and under solvent free conditions (180 °C, 3 h) results in all cases in the selective formation of benzamide with yields of up to 96%, thereby outperforming by far the reactions in which the common 2-pyridyldiphenylphosphane is used as the 1,3-P,N ligand. Read More

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http://dx.doi.org/10.1021/acs.organomet.7b00057DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5350608PMC
March 2017
19 Reads

Electron Transfer and Modification of Oligosilanylsilatranes and Related Derivatives.

Organometallics 2017 Jan 20;36(2):342-351. Epub 2016 Dec 20.

Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.

Several silatranyl -substituted oligosilanes were prepared starting from bis(trimethylsilyl)silatranylsilanide. Electrochemical and theoretical investigations of some oligosilanes revealed that electrooxidation occurs by formation of a short-lived cation radical. This species undergoes structural relaxation to form a pair of conformers, with endo and exo relationships with respect to the Si-N interaction. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5264216PMC
January 2017
5 Reads

Synthesis and Properties of "Sandwich" Diimine-Coinage Metal Ethylene Complexes.

Organometallics 2016 Sep 31;35(17):2938-2943. Epub 2016 Aug 31.

Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States.

Synthesis and full characterization of cationic isostructural "sandwich" diimine-coinage metal ethylene complexes are reported. Ethylene self-exchange kinetics proceeds by an associative exchange mechanism for Cu and Au complexes. The fastest ligand exchange was observed for Ag complex . Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00487DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5019172PMC
September 2016
2 Reads

Basic Reactivity Pattern of a Cyclic Disilylated Germylene.

Organometallics 2016 Aug 3;35(16):2728-2737. Epub 2016 Aug 3.

Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.

In order to estimate the reactivity of disilylated germylene phosphine adducts, a cyclic version of this compound class was reacted with a number of different reagents. Reactions with the chalcogens sulfur, selenium, and tellurium led to dimers of the heavy ketone analogues. Reactions with water and ethyl bromide proceeded to give the respective oxidized germanol and germyl bromide. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00482DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4997532PMC
August 2016
2 Reads

Catalytic Synthesis of Substituted Indoles and Quinolines from the Dehydrative C-H Coupling of Arylamines with 1,2- and 1,3-Diols.

Organometallics 2016 Jun 27;35(11):1973-1977. Epub 2016 May 27.

Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201-1881 United States.

The cationic ruthenium-hydride complex catalyzes dehydrative C-H coupling reaction of arylamines with 1,2-diols to form the indole products. The analogous coupling of arylamines with 1,3-diols afforded the substituted quinolines. The catalytic method directly forms these coupling products in a highly regioselective manner without generating any toxic byproducts. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00273DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261509PMC

Titanocene-Gold Complexes Containing N-Heterocyclic Carbene Ligands Inhibit Growth of Prostate, Renal, and Colon Cancers in Vitro.

Organometallics 2016 May 15;35(9):1218-1227. Epub 2016 Apr 15.

Department of Chemistry, Brooklyn College, The City University of New York, Brooklyn, New York 11210, United States; Chemistry and Biology Ph.D. Programs, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, New York 10016, United States; Chemistry and Biology Ph.D. Programs, The Graduate Center, The City University of New York, 365 Fifth Avenue, New York, New York 10016, United States.

We report on the synthesis, characterization, and stability studies of new titanocene complexes containing a methyl group and a carboxylate ligand (mba = -OC(O)--CH-S-) bound to gold(I)-N-heterocyclic carbene fragments through the thiolate group: [(η-CH)TiMe(μ-mba)Au(NHC)]. The cytotoxicities of the heterometallic compounds along with those of novel monometallic gold-N-heterocyclic carbene precursors [(NHC)Au(mbaH)] have been evaluated against renal, prostate, colon, and breast cancer cell lines. The highest activity and selectivity and a synergistic effect of the resulting heterometallic species was found for the prostate and colon cancer cell lines. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4863200PMC
May 2016
2 Reads

A Transmetalation Reaction Enables the Synthesis of [F]5-Fluorouracil from [F]Fluoride for Human PET Imaging.

Organometallics 2016 Apr 14;35(7):1008-1014. Epub 2016 Feb 14.

Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States; Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114, United States; Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.

Translation of new F-fluorination reactions to produce radiotracers for human positron emission tomography (PET) imaging is rare because the chemistry must have useful scope and the process for F-labeled tracer production must be robust and simple to execute. The application of transition metal mediators has enabled impactful F-fluorination methods, but to date none of these reactions have been applied to produce a human-injectable PET tracer. In this article we present chemistry and process innovations that culminate in the first production from [F]fluoride of human doses of [F]5-fluorouracil, a PET tracer for cancer imaging in humans. Read More

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http://dx.doi.org/10.1021/acs.organomet.6b00059DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4829938PMC
April 2016
21 Reads

Facile Arylation of Four-Coordinate Boron Halides by Borenium Cation Mediated Boro-desilylation and -destannylation.

Organometallics 2015 Dec 8;34(24):5767-5774. Epub 2015 Dec 8.

School of Chemistry, University of Manchester , Manchester M13 9PL, United Kingdom.

The addition of AlCl to four-coordinate boranes of the general formula (C-N-chelate)BCl results in halide abstraction and formation of three-coordinate borenium cations of the general formula [(C-N-chelate)BCl]. The latter react with both arylstannanes and arylsilanes by boro-destannylation and -desilylation, respectively, to form arylated boranes. Catalytic quantities of AlCl were sufficient to effect high-yielding arylation of (C-N-chelate)BCl. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00857DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4819459PMC
December 2015
20 Reads

In-Depth Assessment of the Palladium-Catalyzed Fluorination of Five-Membered Heteroaryl Bromides.

Organometallics 2015 Oct 20;34(19):4775-4780. Epub 2015 Aug 20.

Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.

A thorough investigation of the challenging Pd-catalyzed fluorination of five-membered heteroaryl bromides is presented. Crystallographic studies and density functional theory (DFT) calculations suggest that the challenging step of this transformation is C-F reductive elimination of five-membered heteroaryl fluorides from Pd(II) complexes. On the basis of these studies, we have found that various heteroaryl bromides bearing phenyl groups in the ortho position can be effectively fluorinated under catalytic conditions. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00631DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4820280PMC
October 2015
5 Reads

Amide-Directed Formation of Five-Coordinate Osmium Alkylidenes from Alkynes.

Organometallics 2016 Jan 31;35(2):91-99. Epub 2015 Dec 31.

Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Universidad de Zaragoza-CSIC , 50009 Zaragoza, Spain.

The amide-directed synthesis of five-coordinate osmium alkylidene derivatives from alkynes is reported. These types of complexes, which have been elusive until now because of the tendency of osmium to give hydride alkylidyne species, are prepared by reaction of the dihydride OsHCl(PPr) () with terminal alkynes containing a distal amide group. Complex reacts with -phenylhex-5-ynamide and -phenylhepta-6-ynamide to give OsCl{=C(CH)(CH) NH(CO)Ph}(PPr) ( = 3 (), 4 ()). Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00777DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4728614PMC
January 2016
2 Reads

Selective Aromatic C-H Hydroxylation Enabled by -Coordination to Iridium(III).

Organometallics 2015 Sep 16;34(18):4626-4631. Epub 2015 Sep 16.

Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.

We report an aromatic C-H hydroxylation protocol in which the arene is activated through -coordination to an iridium(III) complex. -Coordination of the arene increases its electrophilicity and allows for high positional selectivity of hydroxylation at the site of least electron density. Through investigation of intermediate -cyclohexadienyl adducts and arene exchange reactions, we evaluate incorporation of arene -activation into a catalytic cycle for C-H functionalization. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00731DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4750501PMC
September 2015
3 Reads

Bonding in Complexes of Bis(pentalene)dititanium, Ti(CH).

Organometallics 2015 Oct 5;34(20):4830-4843. Epub 2015 Jul 5.

Department of Chemistry, School of Life Sciences, University of Sussex , Brighton BN1 9QJ, U.K.

Bonding in the bis(pentalene)dititanium "double-sandwich" species TiPn (Pn = CH) and its interaction with other fragments have been investigated by density functional calculations and fragment analysis. TiPn with symmetry has two metal-metal bonds and a low-lying metal-based empty orbital, all three frontier orbitals having a symmetry. The latter may be regarded as being derived by symmetric combinations of the classic three frontier orbitals of two bent bis(cyclopentadienyl) metal fragments. Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.5b00363
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http://dx.doi.org/10.1021/acs.organomet.5b00363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4623488PMC
October 2015
6 Reads

The Reductive Activation of CO Across a Ti=Ti Double Bond: Synthetic, Structural, and Mechanistic Studies.

Organometallics 2015 Oct 4;34(20):4816-4829. Epub 2015 Jul 4.

Department of Chemistry, School of Life Sciences, University of Sussex , Brighton BN1 9QJ, U.K.

The reactivity of the bis(pentalene)dititanium double-sandwich compound TiPn () (Pn = 1,4-{SiPr}CH) with CO is investigated in detail using spectroscopic, X-ray crystallographic, and computational studies. When the CO reaction is performed at -78 °C, the 1:1 adduct is formed, and low-temperature spectroscopic measurements are consistent with a CO molecule bound symmetrically to the two Ti centers in a μ:η,η binding mode, a structure also indicated by theory. Upon warming to room temperature the coordinated CO is quantitatively reduced over a period of minutes to give the bis(oxo)-bridged dimer and the dicarbonyl complex . Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.5b00315
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http://dx.doi.org/10.1021/acs.organomet.5b00315DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4623487PMC
October 2015
5 Reads

Reversible Borylene Formation from Ring Opening of Pinacolborane and Other Intermediates Generated from Five-Coordinate Tris-Boryl Complexes: Implications for Catalytic C-H Borylation.

Organometallics 2015 Oct 11;34(19):4732-4740. Epub 2015 Aug 11.

Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, Michigan 48824-1322 United States.

Catalytic C-H borylation using the five-coordinate tris-boryl complex (dippe)Ir(Bpin) (, dippe = 1,2-bis(diisopropylphosphino)ethane) has been examined using P{H} and H NMR spectroscopy. Compound was shown to react rapidly and reversibly with HBpin to generate a six-coordinate borylene complex, (dippe)Ir(H)-(Bpin)(BOCMeCMeOBpin) (), whose structure was confirmed by X-ray crystallography. Under catalytic conditions, the H generated from C-H borylation converted compound to a series of intermediates. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00525DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5297890PMC
October 2015
12 Reads

Halide-Mediated -Deprotonation Reactions Applied to the Synthesis of 1,2- and 1,3-Disubstituted Ferrocene Derivatives.

Organometallics 2015 Aug 29;34(15):3820-3832. Epub 2015 Jul 29.

Institute of Organic Chemistry, University of Vienna , Währinger Straße 38, A-1090 Vienna, Austria.

The -deprotonation of halide-substituted ferrocenes by treatment with lithium tetramethylpiperidide (LiTMP) has been investigated. Iodo-, bromo-, and chloro-substituted ferrocenes were easily deprotonated adjacent to the halide substituents. The synthetic applicability of this reaction was, however, limited by the fact that, depending on the temperature and the degree of halide substitution, scrambling of both iodo and bromo substituents at the ferrocene core took place. Read More

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http://pubs.acs.org/doi/10.1021/acs.organomet.5b00464
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http://dx.doi.org/10.1021/acs.organomet.5b00464DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4534838PMC
August 2015
12 Reads

Wagner-Meerwein-Type Rearrangements of Germapolysilanes - A Stable Ion Study.

Organometallics 2015 Aug 23;34(15):3756-3763. Epub 2015 Jul 23.

Institut für Chemie, Carl von Ossietzky Universität Oldenburg , Carl von Ossietzky-Strasse 9-11, D-26129 Oldenburg, Federal Republic of Germany.

The rearrangement of tris(trimethylsilyl)silyltrimethylgermane to give tetrakis(trimethylsilyl)germane was investigated as a typical example for Lewis acid catalyzed Wagner-Meerwein-type rearrangements of polysilanes and polygermasilanes. Direct Si NMR spectroscopic evidence is provided for several cationic intermediates during the reaction. The identity of these species was verified by independent synthesis and NMR characterization, and their transformation was followed by NMR spectroscopy. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00431DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4534834PMC
August 2015
3 Reads

Oligosilanylsilatranes.

Organometallics 2015 Aug 28;34(15):3721-3731. Epub 2015 Jul 28.

Institut für Anorganische Chemie der Technischen Universität Graz and Institut für Chemie, der Karl Franzens Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.

Oligosilanes with attached silatranyl units were obtained by reactions of potassium oligosilanides with a silatranyl triflate. Interaction between Si and N atoms was observed in the Si NMR spectra (upfield-shifted SiO resonances) and in the solid-state structures (Si-N distances between 2.29 and 2. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00404DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4534837PMC
August 2015
2 Reads

Promoting C-C Bond Coupling of Benzyne and Methyl Ligands in Electron-Deficient (triphos)Pt-CH Complexes.

Organometallics 2015 Jun 2;34(12):2707-2709. Epub 2015 Jun 2.

Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.

In situ generated benzyne reacts at room temperature with (triphos)Pt-CH to form a five-coordinate π-complex () that is isolable and stable in solution. Thermolysis of at 60 °C generates (triphos)Pt(o-tolyl) (), which is the product of formal migratory insertion of CH onto the coordinated benzyne. The reaction of with the acid PhNH yields toluene at room temperature over the course of 8 h, while the same reaction with only proceeds to 40% conversion over 2 days. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4480611PMC
June 2015
4 Reads

Contrasting Anticancer Activity of Half-Sandwich Iridium(III) Complexes Bearing Functionally Diverse 2-Phenylpyridine Ligands.

Organometallics 2015 Jun 25;34(11):2683-2694. Epub 2015 Mar 25.

Department of Chemistry, University of Warwick , Gibbet Hill Road, Coventry, CV4 7AL, U.K.

We report the synthesis, characterization, and antiproliferative activity of 15 iridium(III) half-sandwich complexes of the type [(η-Cp*)Ir(2-(R'-phenyl)-R-pyridine)Cl] bearing either an electron-donating (-OH, -CHOH, -CH) or electron-withdrawing (-F, -CHO, -NO) group at various positions on the 2-phenylpyridine (2-PhPy) chelating ligand giving rise to six sets of structural isomers. The X-ray crystal structures of [(η-Cp*)Ir(2-(2'-fluorophenyl)pyridine)Cl] () and [(η-Cp*)Ir(2-(4'-fluorophenyl)pyridine)Cl] () exhibit the expected "piano-stool" configuration. DFT calculations showed that substituents caused only localized effects on the electrostatic potential surface of the chelating 2-PhPy ligand of the complexes. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00097DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4482135PMC
June 2015
8 Reads

Gold(I) and Gold(III) Complexes of Cyclic (Alkyl)(amino)carbenes.

Organometallics 2015 Jun 29;34(11):2439-2454. Epub 2015 Jan 29.

School of Chemistry, University of East Anglia , Norwich NR4 7TJ, U.K.

The chemistry of Au(I) complexes with two types of cyclic (alkyl)(amino)carbene (CAAC) ligands has been explored, using the sterically less demanding dimethyl derivative CAAC and the 2-adamantyl ligand CAAC. The conversion of (CAAC)AuCl into (CAAC)AuOH by treatment with KOH is significantly accelerated by the addition of BuOH. (CAAC)AuOH is a convenient starting material for the high-yield syntheses of (CAAC)AuX complexes by acid/base and C-H activation reactions (X = OAryl, CFCO, N(Tf), CPh, CF, CHF, CHF, CHC(O)CHOMe, CH(Ph)C(O)Ph, CHSOPh), while the cationic complexes [(CAAC)AuL] (L = CO, CN Bu) and (CAAC)AuCN were obtained by chloride substitution from (CAAC)AuCl. Read More

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http://dx.doi.org/10.1021/om501211pDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4482412PMC
June 2015
2 Reads

Reactivity of Gold Hydrides: O Insertion into the Au-H Bond.

Organometallics 2015 Jun 18;34(11):2098-2101. Epub 2014 Dec 18.

Wolfson Materials and Catalysis Centre, School of Chemistry, University of East Anglia , Norwich NR4 7TJ, U.K.

Dioxygen reacts with the gold(I) hydride (IPr)AuH under insertion to give the hydroperoxide (IPr)AuOOH, a long-postulated reaction in gold catalysis and the first demonstration of O activation by Au-H in a well-defined system. Subsequent condensation gave the peroxide (IPr)Au-OO-Au(IPr) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene). The reaction kinetics are reported, as well as the reactivity of Au(I) hydrides with radical scavengers. Read More

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http://dx.doi.org/10.1021/om501165zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4482408PMC
June 2015
11 Reads

Catalytic Transfer of Magnetism using a Neutral Iridium Phenoxide Complex.

Organometallics 2015 Jun;34(12):2997-3006

Department of Chemistry, University of York, Heslington, YO10 5DD; Tel: 01904 322564.

A novel neutral iridium carbene complex Ir(κC,O-L)(COD) () [where COD = cyclooctadiene and L = 3-(2-methylene-4-nitrophenolate)-1-(2,4,6-trimethylphenyl) imidazolylidene] with a pendant alkoxide ligand has been prepared and characterized. It contains a strong Ir-O bond and X-ray analysis reveals a distorted square planar structure. NMR spectroscopy reveals dynamic solution state behavior commensurate with rapid seven-membered ring flipping. Read More

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http://dx.doi.org/10.1021/acs.organomet.5b00311DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5321507PMC
June 2015
8 Reads

Metalated Oligosilanylstibines.

Organometallics 2015 Apr 10;34(8):1431-1439. Epub 2015 Apr 10.

Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.

The reaction of a cyclic disilylated bromostibine with magnesium yields a rare example of a magnesium stibide that can be silylated with trimethylchlorosilane. Reaction of the thus-obtained trisilylated stibine with potassium -butoxide gives a potassium stibide in a clean reaction. Attempts to obtain an antimony-containing oligosilanide did not lead to the expected compound but to another potassium stibide, which presumably forms from the initially formed silanide by a 1,2-silyl shift. Read More

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http://dx.doi.org/10.1021/om501297hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4413693PMC
April 2015
2 Reads

Oligosilanylated Antimony Compounds.

Organometallics 2015 Apr 10;34(8):1419-1430. Epub 2015 Apr 10.

Institut für Anorganische Chemie and Institut für Physikalische und Theoretische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.

By reactions of magnesium oligosilanides with SbCl, a number of oligosilanylated antimony compounds were obtained. When oligosilanyl dianions were used, either the expected cyclic disilylated halostibine was obtained or alternatively the formation of a distibine was observed. Deliberate formation of the distibine from the disilylated halostibine was achieved by reductive coupling with CK. Read More

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http://dx.doi.org/10.1021/om501075vDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4413694PMC
April 2015
2 Reads

Synthesis, Spectroscopy, and Electrochemistry of (α-Diimine)M(CO)Br, M = Mn, Re, Complexes: Ligands Isoelectronic to Bipyridyl Show Differences in CO Reduction.

Organometallics 2014 Sep;34(1):3-12

Department of Chemistry, University of Missouri, Columbia, Missouri 65211, United States.

The synthesis and characterization of new Mn(I)- and Re(I)-centered organometallic complexes fashioned with 1,4-diazabutadiene (DAB) ligands is reported. Ten compounds of the type -(α-diimine)M(CO)Br (M = Mn, Re) were obtained in moderate to excellent yield (35-80%) and high purity from the coordination of the five ligands with M(CO)Br in refluxing ethanol. Despite the electronic similarity of DAB to 2,2'-bipyridyl, the complexes described herein were poor mediators of electrochemical CO conversion to CO, but provide insight into the role of redox-active ligands in catalysis. Read More

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http://pubs.acs.org/doi/10.1021/om500838z
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http://dx.doi.org/10.1021/om500838zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4399245PMC
September 2014
15 Reads