12079-65-1Relevant articles and documents
UNTERSUCHUNG DER EIGENSCHAFTEN EINES UNGEWOEHNLICHEN DISCHWEFELLIGANDEN: VERGLEICHENDE BETRACHTUNG DER CHEMIE VON (C5Me5)2Cr21-S2)(μ,η2-S2)(μ-S)> und (C5Me5)2Mo2(μ,η2-S2)(μ-S)2
Brunner, Henri,Kauermann, Heike,Meier, Walter,Wachter, Joachim
, p. 183 - 192 (1984)
The uncoordinated sulphur of the iso-μ(η1-S2) ligand in (C5Me5)2Cr2S5 is easily abstracted by PPh3 causing formation of (C5Me5)2Cr2S4, isoelectronic with (C5Me5)2Mo2(μ-S2)(μ-S)2.From the nature of the products PF6, (
Investigation into the reactivity of M(ii5-C5R5)(CO)2(alkane) (M = Mn or Re; R = H, Me or Ph; alkane = n-heptane or cyclopentane) and Re(Tj5-C5H5)(CO)2(Xe) in solution at cryogenic and room temperature
Childs, Gavin I.,Colley, Christopher S.,Dyer, Joanne,Grills, David C.,Sun, Xue-Zhong,Yang, Jixin,George, Michael W.
, p. 1901 - 1906 (2000)
A series of M(r|5-C5R5)(CO)2(C5H10) complexes (R = H, Me or Ph; M = Mn or Re) have been characterised at low (Re only) and room temperature (R = H only) using infrared spectroscopy. The decay rates of these complexes have been measured and compared to tho
Comparative oxidative addition of transition-metal iodocyclopentadienyl complexes (η5-C5H4-I)MLn, (M = Re, Mn, Fe) with a palladium(O) complex: Relevance to the efficiency of catalytic reactions
Amatore, Christian,Godin, Beatrice,Jutand, Anny,Ferber, Benoit,Top, Siden,Jaouen, Gerard
, p. 3887 - 3890 (2007)
The rate constants of the oxidative addition of the transition-metal iodocyclopentadienyl complexes (η-C5H4-I)-MLn (ML n = Mn(CO)3 (1a), Re(CO)3 (1b), CpFe (1c)) with Pd0(PPh3)4 have been determined in DMF. As expected, the oxidative addition is faster for the electron-acceptor groups Mn-(CO)3 and Re(CO)3 than for the electron-donor group FeCp, with the reactivity order 1a > 1b ? 1c. Comparison of the rate constants of the oxidative additions affords a new strategy for the evaluation of the electronic properties of transitionmetal units ligated to the iodocyclopentadienyl moiety with the following decreasing electron-acceptor properties: Mn(CO)3 > Re(CO)3 ? FeCp. The complexes formed in the oxidative addition are characterized as trans-[(η5- C5H4)PdI(PPh3)2]MLn (MLn = Mn(CO)3 (2a), Re(CO)3 (2b), CpFe (2c)) with the decreasing stability order in DMF: 2c ? 2b > 2a. The relevance to the efficiency of palladium-catalyzed Stille or Sonogashira reactions from related complexes 1 is discussed.
Kolobova, N. E.,Derunov, V. V.
, (1987)
Abel, E. W.,McLean, R. A. N.,Moorhouse, S.
, p. 587 - 590 (1971)
The chemistry of monoanionic carbaborane ligands. Synthesis, and molecular and electronic structure of , and order-of-magnitude improved structure of <η-C5H5)Mn(CO)3
Cowie, Jill,Hamilton, Ewan J.M.,Laurie, Jill C.V.,Welch, Alan J.
, p. 1 - 13 (1990)
The synthesis, and spectroscopic and structural characterisation of a transition metal complex of, formally, a monoanionic carbaborane ligand are described.Two molecules of crystallise in the triclinic space group P1,
Unusual reactions of a cationic carbyne complex of manganese with carbonyliron dianions to form a novel dimetal carbene-bridged complex [MnFe{μ-C(COEt)Ph}(η-C5H5)(CO)5]
Yu, Yong,Chen, Jiabi,Chen, Jian,Zheng, Peiju
, p. 1443 - 1447 (1996)
The reaction of [Mn(≡CPh)(μ-C5H5)(CO)2]BBr4 1 with [NEt4]2[Fe2(CO)8] in tetrahydrofuran at low temperature gave a novel heteronuclear dimetal carbene-bridged complex [MnFe{μ-C(COEt)Ph}(η-C5H5)(CO)5] 3, and a dimetal dicarbene complex [{(OC)2(η-C5H5)Mn(=CPh)}2Fe 2(CO)8] 4, as well as [Mn(η-C5H5)-(CO)3] 2. The same products, 2 and 3, were obtained from the reaction of 1 with Na2[Fe(CO)4]. The structure of 3 has been established by X-ray crystallography.
η2 Complexes of Cyclic Polyolefins: Crystal Structure of 2-C8H8)(η-C5H5)>
Benson, Ian B.,Knox, Selby A. R.,Stansfield, Robert F. D.,Woodward, Peter
, p. 51 - 55 (1981)
Treatment of (thf = tetrahydrofuran) with cyclo-octatetraene produces 2-C8H8)(η-C5H5)>, whose structure was determined by X-ray-diffraction.Crystals are monoclinic, space group P21/c, with four molecules in a unit cell of dimensions a=10.813(7), b=6.606(4), c=17.164(9) Angstroem, β=94.68(5)deg.The structure was solved by conventional techniques and refined by least squares to R 0.034 for 2 787 independent diffracted intensities.The molecule contains an η2-cyclo-octatetraene ligand which possesses mirror symmetry and presents the convex face of a tub conformation towards the cyclopentadienyl ring.Nuclear magnetic resonance spectra show that the complex is non-fluxional below the temperature (ca.75 deg C) at which it decomposes to the dimanganese μ-cyclo-octatetraene complex 2(μ-C8H8)>.The η2-cyclo-octatetraene is readily displaced by phosphine ligands.Analogous η2-olefin complexes of manganese are obtained from cycloheptatriene and cyclo-octa-1,3,6-triene.
Manganese alkane complexes: An IR and NMR spectroscopic investigation
Calladine, James A.,Duckett, Simon B.,George, Michael W.,Matthews, Steven L.,Perutz, Robin N.,Torres, Olga,Vuong, Khuong Q.
, p. 2303 - 2310 (2011)
Manganese propane and manganese butane complexes derived from CpMn(CO) 3 were generated photochemically at 130-136 K with the alkane as solvent and characterized by FTIR spectroscopy and by 1H NMR spectroscopy with in situ laser photolysis. Time-resolved IR spectroscopic measurements were performed at room temperature with the same laser wavelength. The ν(CO) bands in the IR spectra of the photoproducts in propane are shifted to low frequency with respect to CpMn(CO)3, consistent with formation of CpMn(CO)2(propane). The 1H NMR spectra conform to the criteria for alkane complexes: a high-field resonance for the η2-CH protons that shifts substantially on partial deuteration of the alkane and exhibits a coupling constant JC-H on 13C-labeling of ca. 120 Hz. The NMR spectrum of each system exhibits two diagnostic product resonances in the high-field region for the η2-CH protons, corresponding to CpMn(CO)2(η 2-C1-alkane) and CpMn(CO)2(η2-C2-alkane) isomers. Partial deuteration of the alkane at C1 results in characteristic strong isotopic perturbation of equilibrium of the η2-CH resonance of CpMn(CO)2(η2-C1-alkane). With propane-13C1, the η2-CH resonance of CpMn(CO)2(η2-C1-alkane) isomer exhibits 13C satellites with JC-H = 119 Hz. The corresponding resonance of CpMn(CO)2(η2-C2-alkane) is identified by use of propane-2,2-d2. The lifetimes of the (η2-C1-alkane) isomers of the manganese complexes were determined by NMR spectroscopy as 22 ± 2 min at 134 K (propane) and 5.5 min at 136 K (butane). The corresponding spectra and lifetimes of the CpRe(CO)2(alkane) complexes were measured for reference (CpRe(CO)2(propane) lifetime ca. 60 min at 161 K; CpRe(CO)2(butane) 13 min at 171 K). The lifetimes determined by IR spectroscopy were similar to those determined by NMR spectroscopy, thereby supporting the assignments. These measurements extend the range of alkane complexes characterized by NMR spectroscopy from rhenium and rhodium derivatives to include less stable manganese derivatives.
An investigation into the reactivity of organometallic noble gas complexes: A time-resolved infrared study in supercritical noble gas and alkane solution at room temperature
Grills, David C.,Sun, Xue Z.,Childs, Gavin I.,George, Michael W.
, p. 4300 - 4307 (2000)
A study investigated the effect of cyclopentadienyl ring substituents on the reactivity of the Group 7 half-sandwich complexes, (η5-C5R5)M(CO)2L (M = Mn and Re; R = H, Me and Et (Mn only); L = Kr and Xe) toward CO in supercritical fluid solution at room temperature. The steric bulk of the three types of ring substituent steadily increased in the order H 5-C5R'5)Mn(CO)2Xe (R' = H and Me) and (η5-C5R'5)Mn(CO)2Kr had very similar reactivity toward CO, while (η5C5Et5)Mn(CO)2L (L = Xe and Kr) were approximately twice as reactive. Experiments with the manganese xenon complexes suggested that the noble gas complexes react with CO in supercritical solution via a dissociative mechanism. This reaction mechanism was further evidenced by temperature dependence studies where the enthalpies of activation were calculated for these noble gas complexes and the analogous alkane complexes.
Transition-metal compounds containing alkynylsilyl groups - Cyclopentadienyl complexes
Hoffmann, Florian,Wagler, Joerg,Roewer, Gerhard
, p. 6018 - 6026 (2013/02/26)
The synthesis of (alkynylsilyl)cyclopentadienyl complexes of titanium and manganese was studied. The titanium compounds PhC≡CMe2SiC 5H4CpTiCl2 (1) and (PhC≡CMe 2SiC5H4)2/su
Cymantrene radical cation family: Spectral and structural characterization of the half-sandwich analogues of ferrocenium ion
Laws, Derek R.,Chong, Daesung,Nash, Karen,Rheingold, Arnold L.,Geiger, William E.
, p. 9859 - 9870 (2009/02/04)
The anodic one-electron oxidation of three members of the half-sandwich family of piano-stool compounds MnCpγ(CO)3, where Cpγ is a generic cyclopentadienyl ligand, has been studied in a CH2Cl2/ [NBu4][TFAB] electrolyte (TFAB = [B(C6F5)4]-). The long-sought 17 e- radical cation of the parent complex MnCp(CO)3 (cymantrene, 1, E1/2 = 0.92 V vs ferrocene) has been shown to be persistent in solutions that use weakly coordinating anions in place of more nucleophilic traditional electrolyte anions. Spectroscopically characterized for the first time, 1+ was shown to absorb in the visible (530 nm), near-IR (2066 nm), and IR (2118, 1934 cm-1) regions. It was ESR-active at low temperatures (g∥ = 2.213, g⊥ = 2.079, A∥ (Mn) = 79.2 G, A⊥ (Mn) = 50 G) and NMR active at room temperature (δ = 22.4 vs TMS). The radical cations of the Cp-functionalized analogues, Mn(η5-C5H 4NH2)(CO)3, 2, E1/2 = 0.62 V, and MnCp*(CO)3 (Cp= η5-C5Me 5, 3), E1/2 = 0.64 V, were generated electrochemically as well by the chemical oxidant [ReCp(CO)3]+. The structures of 2+ and 3+ were determined by X-ray crystallographic studies of their TFAB salts. Compared to the structures of the corresponding neutral compounds, the cations showed elongated Mn-C(O) bonds and shortened C-O bonds, displaying the effect of diminished metal-to-CO backbonding. The bond-length changes in the Mn(CO)3 moiety were much larger in 3 + (avg changes, Mn-C(O) = + 0.142 A, C-O = -0.063 A) than in 2+ (avg changes, Mn-C(O) = + 0.006 A, C-O = -0.003 A). Although there were only minor changes in the metal-to-center ring distances upon oxidation of either 2 or 3, there was decidedly less bending of the C(N) atom out of the cyclopentadienyl plane in 2+ compared to 2. The optical, vibrational, and magnetic resonance spectra of radicals 2 + and 3+ were also observed. The spectral data argue for the SOMOs of the 17-electron species being largely located on the Mn(CO) 3 moiety, having 40-50% Mn d-orbital character, with the ground states of the radicals, most likely 2A″, lying close in energy (within about 6000 cm-1) to excited states that are responsible for their rapid electronic relaxations. The cymantrenyl moiety is proposed as an anodic redox tag (or label) having physical and chemical properties that are significantly different from those of its ferrocenyl analogue.
