On Tetrachlorophosphonium Chlorometallates of Rhenium and Molybdenum: Syntheses, Crystal Structures, and Magnetism of [PCl
4
]
2
[Re
2
Cl
10
] and [PCl
4
]
3
[ReCl
6
]
2
, and the Magnetic Properties of [PCl
4
]
2
[Mo
2
Cl
10
]
摘要:
MoCl4, ReCl4, and ReCl5 react with PCl5 in sealed glass ampoules at temperatures between 220 degrees and 320 degrees to [PCl4](2)[Mo2Cl10] (1) [PCl4](2)[Re2Cl10] (2), and [PCl4](3)[ReCl6](2) (3) 2 crystallizes isotypically to the previously reported 1 and the respective titanium and tin containing analogues. The structure (triclinic, P (1) over bar, Z = 1, a = 897.3(2), b = 946.0(2), c = 687.13(9) pm, alpha = 95.59(2)degrees, beta = 95.80(2)degrees, gamma = 101.07(2)degrees, V = 565.4(2) 10(6) pm(3)) is built of tetrahedral [PCl4](+) and edge sharing double octahedral [Re2Cl10](2-) ions and can be derived from a hexagonal closest packing of Cl- ions with tetrahedral and octahedral holes partially filled by P(V) and Re(IV), respectively. 3 crystallizes isotypically to [PCl4](3)[PCl6][MCl6] (M = Ti, Sn) (tetragonal, P 4(2)/mbc, Z = 4, a = 1496.2(1), c = 1363.2(2) pm). Because no evidence was found for the presence of [PCl6](-) ions, Re in 3 has to be of mixed valency with Re-IV and Re-V sharing the same crystallographic site. The structure can be derived from a cubic closest packing or alternatively from an only sparsely distorted body centered cubic arrangement of Cl- ions which is rarely found for anion arrays. The tetrahedral and octahedral holes are partially filled by PV and M-IV/V, respectively. Magnetic measurements show all three compounds to be paramagnetic and confirm the oxidation state IV for Mo and Re in 1 and 2 and the mixed valence (IV/V) for Re in 3.
Hydrodesulfurization catalysis by transition metal sulfides
作者:T PECORARO
DOI:10.1016/0021-9517(81)90303-1
日期:1981.2
effect in the hydrodesulfurization of dibenzothiophene by transitionmetalsulfides is “electronic,” i.e., it is related to the position the metal occupies in the periodic table. This effect, which determines the ability of the transitionmetalsulfides to catalyze the HDS reaction, varies over three orders of magnitude across the periodic table. The first-row transitionmetalsulfides are relatively
Synthesis, characterization, and determination antioxidant activities for new Schiff base complexes derived from 2-(1H-indol-3-yl)-ethylamine and metal ion complexes
作者:May Juda. Kareem、Abbas Ali Salih Al-Hamdani、Young Gun Ko、Wail Al Zoubi、Saad G. Mohammed
DOI:10.1016/j.molstruc.2020.129669
日期:2021.5
Abstract Tetradentate bidentate Schiffbase (L1) from 4-amino-1.5-dimethyl-2-phenyl-1.2-dihydro-pyrazol-3-one and 2-(1H-indol-3-yl)-ethylamine and benzene-1.4-dicarbaldehyde was synthesized and characterized as novel antioxidants. The Schiffbase and its metalcomplexes Mn(II), Co(II),Cu(II), Zn(II), Cd(II) and Re(V) have been characterized by elemental microanalysis, metal content, chloride-containing
The compounds Re3E7X7 are obtained from rhenium tetrahalides ReX4, elemental chalcogens and the respective chalcogen halides E2X2 or SeX4 (E = S, Se; X = Cl, Br). Re3S7Cl7, Re3S7Br7 and Re3Se7Br7 are formed in solutions of sulfur or selenium halides or SiBr4 in form of black crystals and crystallize isotypically in the trigonal space group P31c. Re3Se7Cl7 is formed by solid state reaction of ReCl4, Se and SeCl4 or by thermal decomposition of Se-4[ReCl6], crystallizing as red, in thin layers transparent crystals in the orthorhombic space group Pbcm. The crystal structures consist of discrete positively charged cluster units and halide ions according to the formula [Re-3(mu(3)-E)(mu(2)-E-2)(3)X-6]X-+(-). In the rhenium triangular clusters the Re-Re distances range from 269,0 to 270,4 pm for the sulfur and from 273,3 to 275,3 pm fur the selenium containing compounds. The Re-3 units are capped by chalcogen atoms, three E-2 groups form bridges over the edges of the Re-3 triangles. The trigonal and the orthorhomhic structure type show differences in the site symmetry of the clusters (C-3 vs. C-5) and in the stacking sequence of the molecules, which are packed in the motif of a closest packing of spheres.