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71.
Organometallic Lewis Acids. XLII. Carbonyl- and Nitrosyl Complexes of Manganese and Rhenium of Weakly Coordinated Anions (Ph3P)2(ON)2MnX, (Ph3P)n(OC)5–nMX (M = Mn, Re; n = 1, 2; X = FBF3, OSO2CF3, OSO2F, OCORf) The complexes (Ph3P)2(ON)2MnX (X = FBF3, OSO2CF3, OSO2F, OCOCF3, OCOC3F7) and (Ph3P)n(OC)5–nMX (M = Mn, Re; n = 1, 2; X = FBF3, OSO2CF3) have been obtained by reaction of (Ph3P)2(ON)2MnH and (Ph3P)n(OC)5–nMeMe with the corresponding acids HX or from (Ph3P)n(OC)5–nReBr (n = 1, 2) with silver salts AgX, respectively. The compounds have been characterized by their IR and partially by 19F-NMR data. An efficient method for the preparation of the hydride (Ph3P)2(ON)2MnH is reported. 相似文献
72.
Evan M. Benbow 《Journal of solid state chemistry》2006,179(12):3989-3996
Eighteen new intermetallic compounds RMn2TrxZn20−x (2<x<7; R=rare-earth metal; Tr=Al, In) were synthesized using low-melting mixtures of (Tr/Zn) as a solvent. Structural refinement using single-crystal X-ray diffraction data shows that the compounds are substituted variants of the cubic CeCr2Al20-type structure (Fd-3m, Z=8; unit cell parameters vary from a=14.1152(3)Å for YbMn2Al5.3Zn14.7 to a=14.8125(4)Å for SmMn2In5.9Zn14.1). The Zn and Tr elements show site preferences in the indium compounds, but not in the aluminum analogs. The substitution of trielide element for zinc modifies the valence electron count of the compounds to allow for the incorporation of Mn into the structure. Magnetic susceptibility data show no evidence of magnetic ordering down to 3 K. 相似文献
73.
74.
《Electroanalysis》2005,17(2):186-190
We report for the first time on the electroassisted biomimetic activation of molecular oxygen by a newly prepared electropolymerized polypyrrole‐manganese phthalocyanine film. The prepared films and their intervention in the electroassisted catalytic reduction of molecular oxygen were analyzed by cyclic voltammetry and UV‐visible spectrophotometry on optically transparent electrodes. The obtained results demonstrate the probable existence of the key‐steps responsible for the suggested formation of the highly reactive manganese oxo intermediate. 相似文献
75.
Jorge Bravo Jesús Castro Soledad García‐Fontn Elvira M. Lamas Pilar Rodríguez‐Seoane 《无机化学与普通化学杂志》2003,629(2):297-302
The manganese carbonyl complex [MnBr(CO)3 L ] ( 1 ), where L = Ph2POCH2CH2OPPh2, was prepared by reacting [MnBr(CO)5] with the bidentate ligand 1, 2‐Bis(diphenylphosphinite)ethane. From this compound and the appropriate phosphite, phosphinite or phosphonite ligands were synthesized the complexes [MnBr(CO)2 LL ′], where L ′ = P(OMe)3 ( 2 ) or P(OEt)3 ( 3 ) and [MnBr(CO)3 L ′2], where L ′ =PPh(OEt)2 ( 4 ) or PPh2(OEt) ( 5 ). The obtained compounds have been characterized by elemental analysis, mass spectrometry, IR and NMR (1H, 13C and 31P) spectroscopies and X‐ray diffractometry for the complexes 1 , 4 and 5 . 相似文献
76.
V. I. Sokolov 《Journal of organometallic chemistry》1995,500(1-2):299-306
Results of a long experience of our group in Moscow in the area of chiral organometallic stereochemistry are described. They embrace optically active organometallic derivatives of mercury, palladium, platinum, functionalized ferrocenes, ruthenocenes, and cymantrenes as well as less common objects such as organometallic fullerenes and the cyclodextrin-metallocenes inclusion complexes. 相似文献
77.
The metal ion distribution on the two metal sites of monoclinic Mn1?xCux(HCOO)2 · 2(H,D)2O mixed crystals are studied by infrared and Raman spectroscopic methods. The spectral regions 3 200–3 400 cm?1 (vOH), 2 875–2 990 cm?1 (vCH), 2 330–2 500 cm?1 (vOD of matrix isolated HDO molecules), 1 350–1 400 cm?1 (symmetric CO2 stretching modes), 570–950 cm?1 (H2O librations), and 490 cm?1 (M? O lattice modes) are mostly sensitive to the metal ions present. The frequency shifts of these bands with increasing content of copper show that Cu2+ prefers the M(1) site, coordinated by HCOO? only. The strengths of the hydrogen bonds increase on going from manganese to copper formate, due to the increased synergetic effect of Cu2+. Solubility and X-ray data of the mixed crystals are included. Irrespective of the same crystal structure, two series of mixed crystals are formed: eutonic area at 0.65 ≥ x ≥ 0.5. 相似文献
78.
A new high-performance liquid chromatographic/electrospray ionization tandem mass spectrometric (HPLC/ESI-MS/MS) method was developed for the simultaneous quantification of 5-fluorouracil (5FU), methotrexate (MTX) and cyclophosphamide (CP) in environmental samples. These compounds, commonly used in the treatment of cancer, are recognized as genotoxic. In order to estimate the occupational exposure of hospital personnel handling these drugs, wipe samples were taken from the working surfaces and directly analyzed (with trophosphamide as internal standard) using a reversed-phase capillary column and MS/MS detection. This is the first HPLC/MS/MS method for the simultaneous determination of 5FU, MTX and CP. The present method offers high sensitivity, with detection limits of 1.1 microg l(-1) for MTX and CP and 33.3 microg l(-1) for 5FU, avoiding any sample preconcentration procedure. Rapidity, specificity, high accuracy (mean values between 92.4 and 99.9%) and precision (mean RSD values between 3.4 and 12.1%) make the method suitable for the routine determination of these three antineoplastic drugs. 相似文献
79.
刘松影 《广东微量元素科学》1998,5(5):48-51
对35名铅作业工城套的行为功能测验,接触组与对照组比较,16项行为功能测验中有14项得分有统计学意义(P〈0.01或P〈0.05),半数项目行为功能测验得分有随着铅作业工人龄增长而呈该增或该减的趋势。作者认为铅对作业工人行为功能的影响是肯定的,用行为功能测验的方法来研究铅的神经毒性是可取的简便方法。 相似文献
80.
职业性铅接触对血压影响的研究 总被引:3,自引:0,他引:3
对118名铅接触工人及108名对照组工人的血压研究发现,在血铅为44.26μg/dL时,铅接触工人的收缩压显著高于对照组,分组研究发现,收缩压在级组剂量-反应关系趋势,在血铅30.20μg/dL,收缩压显著高于对照组,多元逐步回归分析发现,在控制一些其他影响血压的因素后,铅接触工人的血铅水平与收缩压和舒张压均有剂量-反应关系。 相似文献