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1.
Helmut Werner Ulrich Schmidt Birgit Weberndrfer Carsten D. Brandt 《无机化学与普通化学杂志》2002,628(11):2383-2394
Mono‐ and Dinuclear Rhodium Complexes with Arsino(phosphino)methanes in Different Coordination Modes The cyclooctadiene complex [Rh(η4‐C8H12)(κ2‐tBu2AsCH2PiPr2)](PF6) ( 1a ) reacts with CO and CNtBu to give the substitution products [Rh(L)2(κ2‐tBu2AsCH2PiPr2)](PF6) ( 2 , 3 ). From 1a and Na(acac) in the presence of CO the neutral compound [Rh(κ2‐acac)(CO)(κ‐P‐tBu2AsCH2PiPr2)] ( 4 ) is formed. The reactions of 1a , the corresponding B(ArF)4‐salt 1b and [Rh(η4‐C8H12)(κ2‐iPr2AsCH2PiPr2)](PF6) ( 5 ) with acetonitrile under a H2 atmosphere affords the complexes [Rh(CH3CN)2(κ2‐R2AsCH2PiPr2)]X ( 6a , 6b , 7 ), of which 6a (R = tBu; X = PF6) gives upon treatment with Na(acac‐f6) the bis(chelate) compound [Rh(κ2‐acac‐f6)(κ2‐tBu2AsCH2PiPr2)] ( 8 ). From 8 and CH3I a mixture of two stereoisomers of composition [Rh(CH3)I(κ2‐acac‐f6)(κ2‐tBu2AsCH2PiPr2)] ( 9/10 ) is generated by oxidative addition, and the molecular structure of the racemate 9 has been determined. The reactions of 1a and 5 with CO in the presence of NaCl leads to the formation of the “A‐frame” complexes [Rh2(CO)2(μ‐Cl)(μ‐R2AsCH2PiPr2)2](PF6) ( 11 , 12 ), which have been characterized crystallographically. From 11 and 12 the dinuclear substitution products [Rh2(CO)2(μ‐X)(μ‐R2AsCH2PiPr2)2](PF6) ( 13 ‐ 16 ) are obtained by replacing the bridging chloride for bromide, hydride or hydroxide, respectively. While 12 (R = iPr) reacts with NaI to give the related “A‐frame” complex 18 , treatment of 11 (R = tBu) with NaI yields the mononuclear chelate compound [RhI(CO)(κ2‐tBu2AsCH2PiPr2)] ( 20 ). The reaction of 20 with CH3I affords the acetyl complex [RhI2{C(O)CH3}(κ2‐tBu2AsCH2PiPr2)] ( 21 ) with five‐coordinate rhodium atom. 相似文献
2.
Fu‐Sheng Guo Yan‐Cong Chen Ming‐Liang Tong Akseli Mansikkamki Richard A. Layfield 《Angewandte Chemie (International ed. in English)》2019,58(30):10163-10167
Abstraction of iodide from [(η5‐C5iPr5)2UI] ( 1 ) produced the cationic uranium(III) metallocene [(η5‐C5iPr5)2U]+ ( 2 ) as a salt of [B(C6F5)4]?. The structure of 2 consists of unsymmetrically bonded cyclopentadienyl ligands and a bending angle of 167.82° at uranium. Analysis of the bonding in 2 showed that the uranium 5f orbitals are strongly split and mixed with the ligand orbitals, thus leading to non‐negligible covalent contributions to the bonding. Investigation of the dynamic magnetic properties of 2 revealed that the 5f covalency leads to partially quenched anisotropy and fast magnetic relaxation in zero applied magnetic field. Application of a magnetic field leads to dominant relaxation by a Raman process. 相似文献
3.
Synthesis and Characterization of Secondary Nitrosamines from Secondary Amines Using Sodium Nitrite and p‐Toluenesulfonic Acid
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We synthesized nitrosamines (R2N? NO) with R=iPr ( 1 ), nPr ( 2 ), nBu ( 3 ), and hydroxyethyl ( 4 ) from the amine using sodium nitrite/p‐toluenesulfonic acid in CH2Cl2. The rate of formation of 1 – 4 increases in the direction iPr<nPr<nBu2CH2OH. Compounds 1 – 3 were obtained as colorless solids, whereas 4 is a bright yellow liquid. Compounds 1 – 4 were characterized by elemental analysis, MS, IR, and multinuclear NMR (1H, 13C, and 15N) spectroscopies. Additionally, we measured the UV/Vis spectra of all compounds, which show maxima of absorption at approximately 221 nm and molar extinction coefficients between 3043 and 4859 L mol?1 cm?1. We calculated the optimized structures of 1 – 4 (B3LYP/6‐311+G(d,p)) and computed the NMR spectroscopic chemical shifts and infrared frequencies. Furthermore, we carried out a natural bond orbital (NBO) analysis of the nitrosamine moiety. Lastly, the compounds described in this work are valuable starting materials for the synthesis of 2‐tetrazenes with potential interest to replace highly toxic hydrazines in rocket propulsion. 相似文献
4.
Victoria L. Blair Luca M. Carrella William Clegg Prof. Jan Klett Dr. Robert E. Mulvey Prof. Dr. Eva Rentschler Prof. Dr. Luca Russo Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(4):856-863
With the aim of introducing the diisopropylamide [NiPr2] ? ligand to alkali‐metal‐mediated manganation (AMMMn) chemistry, the temperature‐dependent reactions of a 1:1:3 mixture of butylsodium, bis(trimethylsilylmethyl)manganese(II), and diisopropylamine with ferrocene in hexane/toluene have been investigated. Performed at reflux temperature, the reaction affords the surprising, ferrocene‐free, hydrido product [Na2Mn2 (μ‐H)2{N(iPr)2}4]?2 toluene ( 1 ), the first Mn hydrido inverse crown complex. Repeating the reaction rationally, excluding ferrocene, produces 1 in an isolated crystalline yield of 62 %. At lower temperatures, the same bimetallic amide mixture leads to the manganation of ferrocene to generate the first trimanganese, trinuclear ferrocenophane, [{Fe(C5H4)2}3{Mn3Na2(NiPr2)2 (HNiPr2)2}] ( 2 ) in an isolated crystalline yield of 81 %. Both 1 and 2 have been characterised by X‐ray crystallographic studies. The magnetic properties of paramagnetic 1 and 2 have also been examined by variable‐temperature magnetisation measurements on powdered samples. For 1 , the room‐temperature value for χT is 3.45 cm3 K mol?1, and on lowering the temperature a strong antiferromagnetic coupling between the two Mn ions is observed. For 2 , the room‐temperature value for χT is 4.06 cm3 K mol?1, which is significantly lower than the expected value for three isolated paramagnetic MnII ions. 相似文献
5.
Two C3‐Symmetric Dy3III Complexes with Triple Di‐μ‐methoxo‐μ‐phenoxo Bridges,Magnetic Ground State,and Single‐Molecule Magnetic Behavior
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Dr. Mikko M. Hänninen Prof. Dr. Antonio J. Mota Dr. Daniel Aravena Prof. Dr. Eliseo Ruiz Prof. Dr. Reijo Sillanpää Dr. Agustín Camón Dr. Marco Evangelisti Prof. Dr. Enrique Colacio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8410-8420
Two series of isostructural C3‐symmetric Ln3 complexes Ln3 ? [BPh4] and Ln3 ? 0.33[Ln(NO3)6] (in which LnIII=Gd and Dy) have been prepared from an amino‐bis(phenol) ligand. X‐ray studies reveal that LnIII ions are connected by one μ2‐phenoxo and two μ3‐methoxo bridges, thus leading to a hexagonal bipyramidal Ln3O5 bridging core in which LnIII ions exhibit a biaugmented trigonal‐prismatic geometry. Magnetic susceptibility studies and ab initio complete active space self‐consistent field (CASSCF) calculations indicate that the magnetic coupling between the DyIII ions, which possess a high axial anisotropy in the ground state, is very weakly antiferromagnetic and mainly dipolar in nature. To reduce the electronic repulsion from the coordinating oxygen atom with the shortest Dy?O distance, the local magnetic moments are oriented almost perpendicular to the Dy3 plane, thus leading to a paramagnetic ground state. CASSCF plus restricted active space state interaction (RASSI) calculations also show that the ground and first excited state of the DyIII ions are separated by approximately 150 and 177 cm?1, for Dy3 ? [BPh4] and Dy3 ? 0.33[Dy(NO3)6], respectively. As expected for these large energy gaps, Dy3 ? [BPh4] and Dy3 ? 0.33[Dy(NO3)6] exhibit, under zero direct‐current (dc) field, thermally activated slow relaxation of the magnetization, which overlap with a quantum tunneling relaxation process. Under an applied Hdc field of 1000 Oe, Dy3 ? [BPh4] exhibits two thermally activated processes with Ueff values of 34.7 and 19.5 cm?1, whereas Dy3 ? 0.33[Dy(NO3)6] shows only one activated process with Ueff=19.5 cm?1. 相似文献
6.
Square‐Planar Ruthenium(II) Complexes: Control of Spin State by Pincer Ligand Functionalization
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Dr. Bjorn Askevold Dr. Marat M. Khusniyarov Dr. Wolfgang Kroener Dr. Klaus Gieb Prof. Paul Müller Dr. Eberhardt Herdtweck Dr. Frank W. Heinemann Dr. Martin Diefenbach Prof. Max C. Holthausen Veacheslav Vieru Prof. Liviu F. Chibotaru Prof. Sven Schneider 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):579-589
Functionalization of the PNP pincer ligand backbone allows for a comparison of the dialkyl amido, vinyl alkyl amido, and divinyl amido ruthenium(II) pincer complex series [RuCl{N(CH2CH2PtBu2)2}], [RuCl{N(CHCHPtBu2)(CH2CH2PtBu2)}], and [RuCl{N(CHCHPtBu2)2}], in which the ruthenium(II) ions are in the extremely rare square‐planar coordination geometry. Whereas the dialkylamido complex adopts an electronic singlet (S=0) ground state and energetically low‐lying triplet (S=1) state, the vinyl alkyl amido and the divinyl amido complexes exhibit unusual triplet (S=1) ground states as confirmed by experimental and computational examination. However, essentially non‐magnetic ground states arise for the two intermediate‐spin complexes owing to unusually large zero‐field splitting (D>+200 cm?1). The change in ground state electronic configuration is attributed to tailored pincer ligand‐to‐metal π‐donation within the PNP ligand series. 相似文献
7.
Dr. Benedict M. Gardner Dr. Gábor Balázs Prof. Dr. Manfred Scheer Dr. Ashley J. Wooles Dr. Floriana Tuna Prof. Eric J. L. McInnes Dr. Jonathan McMaster Dr. William Lewis Prof. Dr. Alexander J. Blake Prof. Dr. Stephen T. Liddle 《Angewandte Chemie (International ed. in English)》2015,54(50):15250-15254
The HAsAsH molecule has hitherto only been proposed tentatively as a short‐lived species generated in electrochemical or microwave‐plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(TrenTIPS)}2(μ‐η2:η2‐As2H2)] ( 3 , TrenTIPS=N(CH2CH2NSiPri3)3; Pri=CH(CH3)2). Complex 3 was prepared by deprotonation and oxidative homocoupling of an arsenide precursor. Characterization and computational data are consistent with back‐bonding‐type interactions from uranium to the HAsAsH π*‐orbital. This experimentally confirms the theoretically predicted excellent π‐acceptor character of HAsAsH, and is tantamount to full reduction to the diarsane‐1,2‐diide form. 相似文献
8.
Summary. The molecular precursors Nb(OiPr)2[OSi(OtBu)3]3 and {Nb(OiPr)4[O2P(OtBu)2]}2 have been prepared. The first compound undergoes facile thermal conversion to high surface area, acidic niobia silica, whereas
the second one thermally decomposes to a low surface area niobium phosphate. 相似文献
9.
The catalytic properties of the complexes (RCp)2ZrCl2 (R=H, Me, Pri, Bun, Bui, Me3Si,cyclo-C6H11), and Me2SiCp*NBuiZrCl2 (Cp*=C5(CH3)4) combined with the AlBui
3−CPh3B(C6F5)4 cocatalyst in ethylene polymerization were studied. The specific activity of the substituted bis-cyclopentadienyl complexes
decreases in the sequence: Me>Pri>Bun>Bui>Me3Si>cyclo-C6H11, which corresponds to the activity sequence for these complexes activated by polymethylaluminoxane (MAO) but is 4–20 times
lower in absolute value. Comparison of the polyethylene samples obtained in the presence of the same complexes with MAO and
AlBui
3−CPh3B(C6F5)4 cocatalysts showed that polyethylene with much higher molecular mass, melting point, and crystallinity is formed in the presence
of the ternary catalytic systems, and this indicates a different nature of the active sites of the catalytic systems. The
effective activation energy of polymerization (≈3.6 kcal mol−1), first order with respect to monomer and ≈0.4 order with respect to organoaluminum component, was found for the (PriCo)2ZrCl2−AlBui
3−CPh3B(C6F5)4 catalytic system. It was proposed on the basis of the kinetic data that AliBu3 enters into the composition of the active site to form a bridged heteronuclear cationic complex.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp 301–307, February, 2000. 相似文献
10.
Fu‐Sheng Guo Yan‐Cong Chen Ming‐Liang Tong Akseli Mansikkamki Richard A. Layfield 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(30):10269-10273
Abstraction of iodide from [(η5‐C5iPr5)2UI] ( 1 ) produced the cationic uranium(III) metallocene [(η5‐C5iPr5)2U]+ ( 2 ) as a salt of [B(C6F5)4]?. The structure of 2 consists of unsymmetrically bonded cyclopentadienyl ligands and a bending angle of 167.82° at uranium. Analysis of the bonding in 2 showed that the uranium 5f orbitals are strongly split and mixed with the ligand orbitals, thus leading to non‐negligible covalent contributions to the bonding. Investigation of the dynamic magnetic properties of 2 revealed that the 5f covalency leads to partially quenched anisotropy and fast magnetic relaxation in zero applied magnetic field. Application of a magnetic field leads to dominant relaxation by a Raman process. 相似文献
11.
《Journal of Coordination Chemistry》2012,65(4):559-571
In strong alkaline media, the reaction of 2-(tert-butylamino)ethanol (3: R?=?But) with CS2 at 0°C produced a cyclic dithiocarbamate, 3-tert-butylthiazolidine-2-thione (1: R?=?But), rather than alkaline metal or ammonium salts of [S2CN(But)CH2CH2OH]?. This is in contrast to isolation of stable alkaline metal or ammonium salts of [S2CN(R)CH2CH2OH]? (R?=?Me, Et, Pr, or CH2CH2OH) obtained in analogous reactions. The use of Ni(OAc)2, both as a source of Ni(II) and a weaker base, in a one-pot reaction with (3: R?=?But) and CS2, successfully gave the first reported metal complex of [S2CN(But)CH2CH2OH]?, namely [Ni{S2CN(But)CH2CH2OH}2] (2: R?=?But). Compounds 1 and 2 have been fully characterized by infrared and NMR spectroscopies, and by X-ray crystallography. DFT calculations on the cyclization and stabilities of [S2CN(R)CH2CH2OH]? (R?=?Pr and But) have been carried out. 相似文献
12.
Helmut Sitzmann 《无机化学与普通化学杂志》1995,621(4):553-556
[(C5H2tBu3-1,2,4)2Pb] ( 1 ), [(C5HiPr4)2Pb] ( 2 ), and [(C5iPr5)2Pb] ( 3 ) have been obtained from PbCl2 and Li(C5H2tBu3-1,2,4), Na(C5HiPr4) and Na(C5iPr5), respectively. 3 exists as a 1 : 1 mixture of meso- 3 and rac- 3 which interconvert at elevated temperature via one-at-a-time rotation of isopropyl groups with ΔG# = 73.0 ± 1.5/73.7 ± 1.5 kJ/mol at 348 K. 3 is slightly bent in the solid state with an angle of 170(1)° between the ring normals. 相似文献
13.
《Tetrahedron letters》1986,27(42):5143-5146
Reaction of the cyclopropenes (3, R1 = Me, R2 = Me), (3, R1 = H, R2 = Pri) and (3, R1 = H, R2 = But) and with one equivalent of m-chloroperbenzoic acid leads to the enones (4) and (7, R = Pri and But respectively, in the last two cases accompanied by about 15% of the regioisomer (8, R = Pri or But. In the case of (3, R1 = Me, R2 = H) oxidation with excess reagent led to the formate (9, R = SiMe3) and two intermediates (11) and (10, R = SiMe3) could be identified. 相似文献
14.
Sabine Schlecht Naim Faza Werner Massa Stefan Dapprich Gernot Frenking Kurt Dehnicke 《无机化学与普通化学杂志》1998,624(6):1011-1014
Trans-methyl-azido-bis(triisopropylphosphine)platinum(II), [PtN3(CH3)(PiPr3)2] [PtN3(CH3)(PiPr3)2] has been prepared by reductive elimination of ethane from [Pt(CH3)3N3]4 in the presence of triisopropylphosphine at 80 °C. The complex is characterized by IR and NMR spectroscopy and by crystal structure determination, as well as by ab initio calculations. [PtN3(CH3)(PiPr3)2], which is in trans-configuration here, crystallizes in the monoclinic space group P21, Z = 2, and with the lattice dimensions a = 806.9(1), b = 1384.3(1), c = 1093.8(1) pm, β = 94.107(10)°. 相似文献
15.
Ferrando-Soria J Pardo E Ruiz-García R Cano J Lloret F Julve M Journaux Y Pasán J Ruiz-Pérez C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(7):2176-2188
A series of neutral oxamato‐bridged heterobimetallic chains of general formula [MCu(Lx)2(S)2] ? p S ? q H2O [p=0–1, q=0–2.5; L1=N‐2,6‐dimethylphenyloxamate, S=DMF with M=Mn ( 1 a ) and Co ( 1 b ); L2=N‐2,6‐diethylphenyloxamate, S=DMF with M=Mn ( 2 a ) and Co ( 2 b ) or S=DMSO with M=Mn ( 2 c ) and Co ( 2 d ); L3=N‐2,6‐diisopropylphenyloxamate, S=DMF with M=Mn ( 3 a ) and Co ( 3 b ) or S=DMSO with M=Mn ( 3 c ) and Co ( 3 d )] were prepared by treating the corresponding anionic oxamatocopper(II) complexes [Cu(Lx)2]2? (x=1–3) with M2+ cations (M=Mn and Co) in DMF or DMSO as the solvent. The single‐crystal X‐ray structures of 2 a and 3 a reveal the occurrence of well‐isolated, zigzag, oxamato‐bridged manganese(II)–copper(II) chains. The intrachain Cu ??? Mn distances across the oxamato bridge are 5.3761(7) and 5.4002(17) Å for 2 a and 3 a , respectively, whereas the shortest interchain Mn ??? Mn distances are 9.4475(16) and 8.1649(14) Å for 2 a and 3 a , respectively. All of these MIICuII chains (M=Mn and Co) exhibit 1D ferrimagnetic behaviour with moderately strong intrachain antiferromagnetic coupling between the square‐planar CuII and octahedral high‐spin MII ions across the oxamato bridge [?J=31.4–35.2 and 33.4–44.8 cm?1, respectively; H =∑i?J S M,i( S Cu,i+ S Cu,i?1)]. Only the CoIICuII chains show slow magnetic relaxation effects characteristic of single‐chain magnets (SCMs). Analysis of the magnetic relaxation dynamics of 3 d shows a thermally activated mechanism (Arrhenius law dependence) with values of the pre‐exponential factor (τ0=2.6×10?9 s) and activation energy (Ea=7.7 cm?1) that are typical of SCMs. In contrast, two relaxation regimes are observed for 2 d in different temperature regions (τ0=3.2×10?10 s and Ea=24.7 cm?1 for T<4.5 K and τ0=3.2×10?14 s and Ea=37.5 cm?1 for T>4.5 K). 相似文献
16.
S. A. Grabovskiy Q. K. Timerghazin N. N. Kabal’nova 《Russian Chemical Bulletin》2005,54(10):2384-2393
Oxidation of a series of tert-butyl ethers ButOR (R = Me, Et, CH2CH2Cl, Pri, Bui), diethyl ether, diisopropyl ether, 1,2-dimethoxyethane, diisobutoxymethane, 1,4-dioxane, and tetrahydrofuran with dimethyldioxirane
(DMDO) was studied. The reaction kinetics obeys the second-order equation w = k[DMDO][ether]. The rate constants in a range of 5–50 °C and the activation parameters of the reaction were determined. The
solvent effect on the oxidation rate was studied. The oxidation products are the corresponding alcohols and carbonyl compounds.
The competition between the nonradical (oxygen insertion) and radical mechanisms of the reaction is discussed. The reactions
of the parent dioxirane and DMDO with a series of methyl ethers MeOr’ (r’ = Me, Et, CH2CH2F, Pri) were studied by the density functional theory (DFT). The (U)B3LYP-6-311G(d,p) method was employed to calculate the geometry
and energies of the reactants and transition states. The data obtained indicate a possible increase in the probability of
oxidation via the radical route and an increase in the activation barrier for the substrates containing electron-withdrawing substituents.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2309–2318, October, 2005. 相似文献
17.
Polarized Neutron Diffraction as a Tool for Mapping Molecular Magnetic Anisotropy: Local Susceptibility Tensors in CoII Complexes
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Dr. Karl Ridier Dr. Béatrice Gillon Dr. Arsen Gukasov Dr. Grégory Chaboussant Dr. Alain Cousson Prof. Dominique Luneau Dr. Ana Borta Dr. Jean‐François Jacquot Dr. Ruben Checa Yukako Chiba Prof. Hiroshi Sakiyama Prof. Masahiro Mikuriya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):724-735
Polarized neutron diffraction (PND) experiments were carried out at low temperature to characterize with high precision the local magnetic anisotropy in two paramagnetic high‐spin cobalt(II) complexes, namely [CoII(dmf)6](BPh4)2 ( 1 ) and [CoII2(sym‐hmp)2](BPh4)2 ( 2 ), in which dmf=N,N‐dimethylformamide; sym‐hmp=2,6‐bis[(2‐hydroxyethyl)methylaminomethyl]‐4‐methylphenolate, and BPh4?=tetraphenylborate. This allowed a unique and direct determination of the local magnetic susceptibility tensor on each individual CoII site. In compound 1 , this approach reveals the correlation between the single‐ion easy magnetization direction and a trigonal elongation axis of the CoII coordination octahedron. In exchange‐coupled dimer 2 , the determination of the individual CoII magnetic susceptibility tensors provides a clear outlook of how the local magnetic properties on both CoII sites deviate from the single‐ion behavior because of antiferromagnetic exchange coupling. 相似文献
18.
Three lanthanide‐based two‐dimensional (2D) coordination polymers (CPs), [Ln(L)(H2O)2]n, {H3L=(HO)2P(O)CH2CO2H; Ln=Dy3+ (CP 1 ), Er3+ (CP 2 )} and [{Gd2(L)2(H2O)3}.H2O]n, (CP 3 ) were hydrothermally synthesized using phosphonoacetic acid as a linker. Structural features revealed that the dinuclear Ln3+ nodes were present in the 2D sheet of CP 1 and CP 2 while in the case of CP 3 , nodes were further connected to each other forming a chain‐type arrangement throughout the network. The magnetic studies show field‐induced slow magnetic relaxation property in CP 1 and CP 2 with Ueff values of 72 K (relaxation time, τ0=3.05×10?7 s) and 38.42 K (relaxation time, τ0=4.60×10?8 s) respectively. Ab‐initio calculations suggest that the g tensor of Kramers doublet of the lanthanide ion (Dy3+ and Er3+) is strongly axial in nature which reflects in the slow magnetic relaxation behavior of both CPs. CP 3 exhibits a significant magnetocaloric effect with ?ΔSm=49.29 J kg?1 K?1, one of the highest value among the reported 2D CPs. Moreover, impedance analysis of all the CPs show high proton conductivity with values of 1.13×10?6 S cm?1, 2.73×10?3 S cm?1 and 2, 6.27×10?6 S cm?1 for CPs 1 – 3 , respectively, at high temperature (>75 °C) and maximum 95 % relative humidity (RH). 相似文献
19.
Two new doubly methoxido-bridged MnIII dinuclear complexes, [MnIII(mphp)(μ-OCH3)(CH3OH)]2·2CH3OH (1) and ([MnIII(ahbz)(μ-OCH3)(CH3OH)]2·2CH3OH (2), have been synthesized by using the tridentate ligands H2mphp (H2mphp = 2-methyl-6-(pyrimidin-2-yl-hydrazonomethyl)-phenol) and H2ahbz (H2ahbz = N-(2-amino-propyl)-2-hydroxy-benzamide). The complexes have been characterized by single-crystal X-ray diffraction analysis and magnetic measurements. Complexes 1 and 2 have a similar dimeric molecular structure. Two [Mn(L)(CH3OH)]+ moieties (L2? = mphp2? or ahbz2?) are bridged by two μ-OCH3? groups in the axial-equatorial asymmetric manner. The coordination geometry of MnIII is an axially elongated octahedron with two oxygens of a methanol ligand and a methoxido ligand situated at the axial positions. Magnetic measurements indicate that 1 and 2 exhibit antiferromagnetic behavior with the fitting parameter of J = ?1.49(3) cm?1, D = ?1.3(1) cm?1, g = 1.98(1) and zJ′ = ?0.18(4) cm?1 for 1, and J = ?1.6(2) cm?1, D = 4.5(3) cm?1, g = 2.06(1) and zJ′ = 1.4(1) cm?1 for 2 on the basis of the spin Hamiltonian ? = ?2J?Mn1?Mn2. 相似文献
20.
Jaroslaw Chojnacki Barbara Becker Antoni Konitz Wieslaw Wojnowski 《无机化学与普通化学杂志》2000,626(10):2173-2177
Compounds of general formula Au{SSi(OR)3}(PPh3), R = Pri ( 1 ), Bus ( 2 ) or But ( 3 ), have been obtained by reaction of AuCl(PPh3) with triethylammonium salts of respective silanethiols, (RO)3SiSH. Molecular and crystal structures of 1 , 2 , and 3 have been determined by the single crystal X‐ray structural analysis. Compounds 1 and 2 are the first structurally characterized metal derivatives of hydrolytically unstable trialkoxysilanethiols (PriO)3SiSH and (BusO)3SiSH. 相似文献