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41.
U. Abram A. Voigt R. Kirmse K. Ortner R. Hübener R. Carballo E. Vazquez-Lopez 《无机化学与普通化学杂志》1998,624(10):1662-1668
Synthesis, Structures, and EPR-Spectra of the Rhenium(II) Nitrosyl Complexes [Re(NO)Cl2(PPh3)(OPPh3)(OReO3)], [Re(NO)Cl2(OPPh3)2(OReO3)], and [Re(NO)Cl2(OPPh3)3](ReO4) The paramagnetic rhenium(II) nitrosyl complexes [Re(NO)Cl2(PPh3)(OPPh3)(OReO3)], [Re(NO)Cl2(OPPh3)2 · (OReO3)], and [Re(NO)Cl2(OPPh3)3](ReO4) are formed during the reaction of [ReOCl3(PPh3)2] with NO gas in CH2Cl2/EtOH. These and two other ReII complexes with 5 d5 ”︁low-spin”︁”︁-configuration can be observed during the reaction EPR spectroscopically. Crystal structure analysis shows linear coordinated NO ligands (Re–N–O-angles between 171.9 and 177.3°). Three OPPh3 ligands are meridionally coordinated in the final product of the reaction, [Re(NO)Cl2(OPPh3)3][ReO4] (monoclinic, P21/c, a = 13.47(1), b = 17.56(1), c = 24.69(2) Å, β = 95.12(4)°, Z = 4). [Re(NO)Cl2(PPh3)(OPPh3)(OReO3)] (triclinic P 1, a = 10.561(6), b = 11.770(4), c = 18.483(8) Å, α = 77.29(3), β = 73.53(3), γ = 64.70(4)°, Z = 2) and [Re(NO)Cl2 (OPPh3)2(OReO3)] (monoclinic P21/c, a = 10.652(1), b = 31.638(4), c = 11.886(1) Å, β = 115.59(1)°), Z = 4) can be isolated at shorter reaction times besides the complexes [Re(NO)Cl3(Ph3P)2], [Re(NO)Cl3(Ph3P) · (Ph3PO)], and [ReCl4(Ph3P)2]. 相似文献
42.
Synthesis, Structure, and Photolysis of Isocyanato Complexes of Rhenium The ReIII isocyanato complex Re(NCO)3(PMe2Ph)3 yields from the reaction of ReCl3(PMe2Ph)3 with an excess of NaOCN in EtOH. It crystallizes in the triclinic space group P 1 with a = 991.8(6), b = 1180.7(6), c = 1348.8(5) pm, α = 89.85(1)°, β = 94.12(1), γ = 111.56(1)°, Z = 2. In the mononuclear complex with an octahedral coordination of the Re atoms the phosphine and isocyanato ligands exhibit a meridional arrangement. By using a deficient amount of NaOCN the mono isocyanato complex Re(NCO)Cl2(PMe2Ph)3 is formed, and part of the educt is transformed to its isomer [(Me2PhP)3Re(μ-Cl)3Re(PMe2Ph)3]Cl3. The mono isocyanato complex forms monoclinic crystals with the space group P21/n and a = 1467.5(7), b = 1310.6(7), c = 1603.2(8) pm, β = 112.08(1)°, Z = 4. The isocyanato ligand is in trans position to a Cl atom, and the phosphine ligands are coordinated in a meridional arrangement. [(Me2PhP)3Re(μ-Cl)3Re(PMe2Ph)3]Cl3 · 2 EtOH crystallizes in the hexagonal space group P63/m with a = 1332.6(2), c = 2300.1(7) pm, Z = 2. The dinuclear complex cation occupies with its center a special position with the symmetry C3h. Photolysis of Re(NCO)Cl2(PMe2Ph)3 results in the cleavage of the isocyanato ligand with release of CO and formation of the nitrido complex ReNCl2(PMe2Ph)3. The reaction of ReNCl2(PMe2Ph)3 with NaOCN affords the complex ReN(NCO)2(PMe2Ph)3. It crystallizes in the space group P21/n with a = 943.0(3), b = 2635.2(4), c = 1212.6(5) pm, β = 109.88(1)°, Z = 4. In this nitrido complex, like in the educt, the phosphine ligands form a meridional arrangement. The nitrido ligand is in trans position to an isocyanato group. The distance Re≡N is 165.9(6) pm. 相似文献
43.
Eliana M.A. Valle Benedicto A.V. Lima Antonio G. Ferreira Fbio B. do Nascimento Victor M. Deflon Izaura C.N. Digenes Ulrich Abram Javier Ellena Eduardo E. Castellano Alzir A. Batista 《Polyhedron》2009,28(16):3473-3478
The reaction of cis-[RuCl2(P–P)(N–N)] type complexes (P–P = 1,4-bis(diphenylphosphino)butane or (1,1′-diphenylphosphino)ferrocene; N–N = 2,2′-bipyridine or 1,10-phenantroline) with monodentate ligands (L), such as 4-methylpyridine, 4-phenylpyridine and benzonitrile forms [RuCl(L)(P–P)(N–N)]+ species. Upon characterization of the isolated compounds by elemental analysis, 31P{1H} NMR and X-ray crystallography it was found out that the type of the L ligand determines its position in relation to the phosphorus atom. While pyridine derivatives like 4-methylpyridine and 4-phenylpyridine coordinate trans to the phosphorus atom, the benzonitrile ligand (bzCN), a good π acceptor, coordinates trans to the nitrogen atom. A 31P{1H} NMR experiment following the reaction of the precursor cis-[RuCl2(dppb)(phen)] with the benzonitrile ligand shows that the final position of the entering ligand in the complex is better defined as a consequence of the competitive effect between the phosphorus atom and the cyano-group from the benzonitrile moiety and not by the trans effect. In this case, the benzonitrile group is stabilized trans to one of the nitrogen atoms of the N–N ligand. A differential pulse voltammetry experiment confirms this statement. In both experiments the [RuCl(bzCN)(dppb)(phen)]PF6 species with the bzCN ligand positioned trans to a phosphorus atom of the dppb ligand was detected as an intermediate complex. 相似文献
44.
ColliderBit: a GAMBIT module for the calculation of high-energy collider observables and likelihoods
The GAMBIT Scanner Workgroup: Csaba Balázs Andy Buckley Lars A. Dal Ben Farmer Paul Jackson Abram Krislock Anders Kvellestad Daniel Murnane Antje Putze Are Raklev Christopher Rogan Aldo Saavedra Pat Scott Christoph Weniger Martin White 《The European Physical Journal C - Particles and Fields》2017,77(11):795
We describe ColliderBit, a new code for the calculation of high energy collider observables in theories of physics beyond the Standard Model (BSM). ColliderBit features a generic interface to BSM models, a unique parallelised Monte Carlo event generation scheme suitable for large-scale supercomputer applications, and a number of LHC analyses, covering a reasonable range of the BSM signatures currently sought by ATLAS and CMS. ColliderBit also calculates likelihoods for Higgs sector observables, and LEP searches for BSM particles. These features are provided by a combination of new code unique to ColliderBit, and interfaces to existing state-of-the-art public codes. ColliderBit is both an important part of the GAMBIT framework for BSM inference, and a standalone tool for efficiently applying collider constraints to theories of new physics. 相似文献
45.
46.
47.
The chemical form of the retention of TcN/et2dtc/2 has been investigated by mass spectrometry. The results indicate that this complex does not undergo ligand exchange reactions with plasma proteins. 相似文献
48.
Anders M. Eliasen Matthew R. Chin Abram J. Axelrod Ruben Abagyan Dionicio Siegel 《Tetrahedron》2018,74(26):3238-3245
The natural products vinaxanthone and xanthofulvin promote regeneration in animal models of spinal cord injury and corneal transplant. However, inhibition of the initially described biological target of these compounds, semaphorin 3A, does not fully account for the recovery demonstrated in vivo following administration of the natural products. Through chemical synthesis substantial quantities of both natural products have been accessed with early reaction development paving the way for synthesizing both compounds. The success of a model system, first disclosed herein, translated to the syntheses of both natural products. Following from this we also report for the first time the discovery of a new target of the natural products, the succinate receptor 1 (SUCNR1). Both natural products function as positive allosteric modulators of SUCNR1. As the first known allosteric modulators of SUCNR1, the compounds represent powerful new tools to understand the pharmacology of SUCNR1 and its control of growth and cellular defense. 相似文献
49.
Asymmetric, potentially pentadentate ligands (H(2)L(3)) are formed by subsequent condensation of a semicarbazide and benzoylhydrazine on 2,6-diacetylpyridine. Two equivalents of H(2)L(3) reacts with CeCl(3).7H(2)O, Ce(SO(4))(2).4H(2)O, or EuCl(3).6H(2)O under formation of [Ln(III)(HL(3))(2)](+) cations (Ln = Ce, Eu) with exclusive deprotonation of the benzoylhydrazone ligand arms. The Ce(4+) ion of the sulfate salt is reduced during the reaction and forms 10-coordinate singly charged complex cations, the structure of which is identical to the product of the reaction of cerium(III) chloride. The exact position of deprotonation in the ligands is resolved by infrared spectroscopy, bond lengths considerations, and the hydrogen bonding in the solid-state structures of the products. A similar approach allows the synthesis of mixed semicarbazone/thiosemicarbazone ligands (H(2)L(4)). The reaction of H(2)L(4) with Sm(NO(3))(3).6H(2)O leads to the first structurally characterized lanthanide complex with thiosemicarbazone coordination. The solid-state structure of the 10-coordinate complex [Sm(HL(4))(2)]NO(3).H(2)O shows exclusive deprotonation of the thiosemicarbazone arms of the ligands. All isolated complexes are air stable and do not undergo ligand exchange reactions or hydrolysis in the presence of water. 相似文献
50.
Alberto Roger Schibli Roger Angst Daniela Schubiger P. August Abram Ulrich Abram Sonja Kaden Th. A. 《Transition Metal Chemistry》1997,22(6):597-601
Transition Metal Chemistry - A detailed investigation of the one-pot synthesis of [NEt4]2[MX3(CO)3] [M=Tc (1a) or Re (1b); X= Cl?, Br?] is presented. The intermediates... 相似文献