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排序方式: 共有1304条查询结果,搜索用时 31 毫秒
31.
Synthesis and Crystal Structure of Hydronium-tris-ethylenediamine-cobalt(rhodium)-μ-trichloro-nonachlorotrirhenate(III)-chloride, H3O[MEn3][Re3Cl12]Cl (M=Co, Rh) The chlorides H3O[MEn3][Re3Cl12]CI (M = Co, 1 ; Rh, 2 ) crystallize from hydrochloric acid solutions of ReCl3 and MEn3 · 3H2O as deep red hexagonal columns. They are isotypic and crystallize with the hexagonal system (P6 , Z = 1; 1: a = 1010.87(3); c = 794.30(4) pm, R = 0.023, Rw = 0.016; 2: a = 1018.58(3); c = 794.74(4) pm, R = 0.026, Rw = 0.018). The anions [Re3Cl12]3? are connected via H3O+ cation (C.N. 3). The large channels that run in the [001] direction contain, alternatively, the cations [MEn3]3+ and the lonesome Cl?-anions 相似文献
32.
Reactivity of Monophosphine Platinum(0) Complexes with SO2 . The addition reaction of (PPh3)Pt(ViSi) (ViSi = {η2-H2C?CHSiMe2}2O) ( 1 ) with SO2 gives within 30 min the red SO2 complex (PPh3)Pt(η2-H2C?CHSiMe2- OSiMe2CH?CH2)(SO2) ( 2 ). A reaction time of 24 h with SO2 leads to the elimination of the ViSi ligand, and the unstable monomeric intermediate (PPh3)Pt(SO2) cyclo- trimerizes to the stable cluster [Pt(PPh3)(SO2)]3 ( 3 ). 3 is also obtained within 30 min by the reaction of (PPh3)Pt(C2H4)2 ( 4 ) with SO2. The crystal structure of 3 has been determined; space group P21/n, Z = 4, a = 1 606.1(3), b = 1 019.3(1), c = 3 624.6(5) pm, β = 93.67°, R/Rw = 0.102/0.121. 相似文献
33.
The thermal reaction between the tris(μ-hydrido)dodecacarbonyltrirhenium (o) cluster and triphenylphosphine or triphenylphosphite results in a trisubstituted rhenium cluster as the major product. The results of an X-ray structural analysis of H3Re2(CO)9(PPh3) are: Mr=1597.57, Monoclinic, P21/n, a=15.598(1), b=9.530(2), c=41.685(3) Å, β=80.60(1)°, V=6113.(1) Å3, Z=4, Dc=1.736 g/cm3, CuKe, λ-1.54056 Å, μ-121.23 cm?1, F(000)=3059.17, room temperature, R=0.049 for 7361 reflections with I≥2.5σ(I). The molecule has a triangular Re2 core coordinated propellerwise by three PPh3 ligands in the molecular plane with virtual C3k symmetry. 相似文献
34.
Rubén A. Machado David Rivillo Lindora D’Ornelas Reinaldo Atencio Esperanza Galarza 《Journal of organometallic chemistry》2004,689(15):2486-2493
The reaction of the labile compound [Re2(CO)8(CH3CN)2] with trans-1,2-bis(2-pyridyl)ethene (C12H10N2) at room temperature in tetrahydrofuran affords the compounds [Re2(μ:η3-C12H10N2)(CO)8] (1) and the oxidative addition product [Re2(μ-H)(μ:η3-C12H9N2)(CO)7] (2). When the reaction is carried out at temperatures of refluxing tetrahydrofuran, besides compounds 1 and 2, the oxidative addition product [Re2(μ-H)(μ:η4-C12H9N2)(CO)6] (3), the insertion product [Re2(μ:η4-C12H10N2)(CO)8] (4) and [Re2(μ:η6-C24H18N4)(CO)6] (5) are obtained. Compound 5 contains the organic ligand rtct-tetrakis(2-pyridyl)cyclobutandiyl which is derived from a [2 + 2] cycloaddition of 1,2-bis(2-pyridyl)ethene mediated by its coordination to the bimetallic framework. The molecular structures of 1, 2, 4 and 5 were confirmed by X-ray crystallographic studies. 相似文献
35.
36.
Addition compounds of Lewis acids MXn and acyl halides R? COX occur as intermediates in Friedel-Crafts acylations. IR and NMR studies on these intermediates have indicated the probable existence of structural isomers. In X-ray structural analysis, it is possible to distinguish two forms, i.e. the molecular form, in which the compounds are present as donor-acceptor complexes R? CXO→MXn, and the ionic form, in which they can be formulated as oxocarbenium salts [R? CO]+[MXn+1]?. The compounds of the donor-acceptor type R? CXO→MXn are characterized by the formation of a coordinate oxygen-metal bond; the transfer of electrons from the oxygen to the metal of the acceptor is always due to a weak donor-acceptor interaction. The positive charge of the aryloxocarbenium ions is partly delocalized over the aromatic nucleus. The positive charge in alkyloxocarbenium ions, on the other hand, is essentially localized on the carbon atom of the carbonyl group, as is confirmed by electron density distribution calculations. 相似文献
37.
Michael Plate Sigrid Wocadlo Werner Massa Kurt Dehnicke Harald Krautscheid 《无机化学与普通化学杂志》1995,621(3):388-392
Functionalized Alkyne Complexes of Tungsten(VI). Syntheses and Crystal Structures of [WCl4(Et? Se? C?C? Se? Et)(THF)] and [WCl4(Et? Te? C?C? Te? Et)(THF)] The title compounds have been prepared by reactions of [WCl4(SEt2)2] with the alkynes Et? X? C?C? X? Et (X = Se, Te) in CCl4 solution and subsequent addition of tetrahydrofurane. Both complexes were characterized by crystal structure determinations. [WCl4(Et? Se? C?C? Se? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 2942 unique reflections, R = 0.038. Lattice dimensions at 20°C: a = 934.2, b = 1639.5, c = 1189.5 pm, β = 96.497°. [WCl4(Et? Te? C?C? Te? Et)(THF)]: Space group P21/n, Z = 4, structure determination with 4097 unique reflections, R = 0.067, Lattice dimensions at ?70°C: a = 899.2, b = 1691.9, c = 1213.3 pm, β = 96.82°. The complexes have monomeric molecular structures with the oxygen atom of the THF molecules in trans-position to the side-on bound alkyne ligands. 相似文献
38.
Thermal reaction of the chloroaryl-chloride complexes trans-(η5-C5Me5)Re(CO)2(ArCl)Cl (ArCl = 3-ClC6H4, 3-ClC6H3(4-Me) and 3,5-Cl2C6H3) in acetonitrile did not interconvert to the cis isomer, instead the complex ReCl(CO)2(NCMe)3 and the corresponding 5-ArCl-1,2,3,4,5-pentamethylcyclopentadiene were formed. Similar reductive elimination products were obtained when the starting rhenium complexes were reacted with trimethylphosphite in toluene. 相似文献
39.
M. Zalewicz 《Monatshefte für Chemie / Chemical Monthly》1997,128(5):431-442
Summary New complex salts of lanthanide thiocyanates with hexamethylenetetramine of the general formulaLn(NCS)3·2[N4(CH2)6·nH2O, whereLn=La,Pr,Nd,Sm,Gd,Dy,Er andn=0–10, have been analyzed. IR spectra have been obtained in the range of 200–4000 cm–1, frequencies of vibrations of low and high hydration state compounds have been analyzed, and differences between the structures of the coordination speheres of these salts are demonstrated. Diffractometric examinations and measurements of the magnetic susceptibility of several salts have been performed.
Synthese und spektroskopische, diffraktometrische und magnetische Untersuchungen von Verbindungen der Lanthaniden mit Rhodanid und Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthaniden mit Rhodanid und Hexamethylentetramin mit der allgemeinen FormelLn(NCS)3·2[N4(CH2)6]·nH2O (Ln=La,Pr,Nd,Sm,Gd,Dy,Er;n=0–10) wurden untersucht. Die IR-Spektren der Verbindungen im Bereich von 200–4000 cm–1 wurden aufgenommen. Die Schwingungsfrequenzen hoch- und niederhydrierter Verbindungen wurden analysiert und die Unterschiede in der Struktur der Koordinationssphäre bestimmt. An einigen Komplexen wurden diffraktometrische Untersuchungen und Messungen der magnetischen Suzaptibilität durchgeführt.相似文献
40.
The reaction of [(CO)PPh3)2Re(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)] (2) with HBF4-Me2O generates [(CO)PPh3)2Re(μ- H)2(μ,η1,η2HNCHPh)Ru(PPh3)2(PhCN)][BF4] (3). Monitoring the reaction by NMR spectroscopy shows the intermediate formation of [(CO)(PPh3)2 HRe(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)][BF4] (4). Attempted reduction of the imine ligand by a nucleophile (H− or CN−) failed, regenerating 2. Under dihydrogen at 50 atm, 3 is slowly transformed into [(CO)(PPh3)2HRe(μ-H)3Ru(PPh3)2(PhCN)][BF4] (5) with liberation of benzyl amine. 相似文献