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1.
Clifton E. F. Rickard Warren R. Roper Alex Williamson L. James Wright 《Angewandte Chemie (International ed. in English)》1999,38(8):1110-1113
Support for key steps of the mechanism for the transition metal catalyzed hydroboration reaction is provided by the characterization and reactions of 1 , a cis-(boryl)(aryl) complex of osmium(II ). This compound readily eliminates o-tolylBcat to give the osmium(0) intermediate 2 , which in the presence of HBcat reestablishes the osmium–boron bond by forming 3 . R=o-tolyl, H2cat=catechol=1,2-(HO)2C6H4. 相似文献
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Synthesis and Crystal Structure of Tetraphenylphosphonium Aqua-bis(tetrasulfido)thionitrosyl Osmate, PPh4[Os(NS)(S4)2(H2O)] PPh4[Os(NS)(S4)2(H2O)] has been prepared as redbrown crystals by reacting PPh4[OsNCl4] with a solution of excess disodium tetrasulfide in dimethylformamide/H2O and characterized by IR spectroscopy and by a crystal structure determination. Space group P21/n, Z = 4, structure solution with 4162 independent reflections, R = 0.059 for reflections with I > 2σ(I). Lattice dimensions at ?40°C: a = 1138.9(5), b = 1301.4(4), c = 2092.7(7) pm, β = 104.74(3)º. Os? N, Os? O, and Os? S distances are 175.2(12), 219.8(12), and 237.5(4)?239.1(4) pm, respectively. The Os?N?S moiety is approximately linear, with an OsNS angle of 171.2(7)º. 相似文献
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Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of ( n ‐Bu4N)2[Os(NCS)6] and ( n ‐Bu4N)3[Os(NCS)6] By tempering the solid mixture of the linkage isomers (n‐Bu4N)3[Os(NCS)n(SCN)6–n] n = 0–5 for a longer time at temperatures increasing from 60 to 140 °C the homoleptic (n‐Bu4N)3[Os(NCS)6] is formed, which on oxidation with (NH4)2[Ce(NO3)6] in acetone yields the corresponding OsIV complex (n‐Bu4N)2[Os(NCS)6]. X‐ray structure determinations on single crystals of (n‐Bu4N)2[Os(NCS)6] (1) (triclinic, space group P 1, a = 12.596(5), b = 12.666(5), c = 16.026(5) Å, α = 88.063(5), β = 80.439(5), γ = 88.637(5)°, Z = 2) and (n‐Bu4N)3[Os(NCS)6] ( 2 ) (cubic, space group Pa 3, a = 24.349(4) Å, Z = 8) have been performed. The nearly linear thiocyanate groups are coordinated with Os–N–C angles of 172.3–177.7°. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constant fd(OsN) is 2.3 ( 1 ) and 2.10 mdyn/Å ( 2 ). 相似文献
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Syntheses and Crystal Structures of [Pd9As8(PPh2)8] and [Pd9Sb6(PPh3)8] [PdCl2(PPh3)2] reacts with As(SiMe3)3 to give the new cluster [Pd9As8(PPh3)8] ( 4 ). 4 has been characterized by X-ray crystal structure analysis. It is a molecule in which four [Pd2(PPh3)2]-units are bridged by As2-units. A further Pd atom is located in the centre of the cluster. 4 crystallizes in the space group C2/c with four formula units per unit cell. The lattice constants at 200 K are: a = 3 970.6(3), b = 1 648.90(16), c = 3 266.30(20) pm, β = 131,44(4)°. The reaction of [PdCl2(PPh3)2] with Sb(SiMe3)3 yields [Pd9Sb6(PPh3)8] ( 5 ). 5 consists of a body centred cubic Pd9-cluster. All of the cube faces are capped by μ4-Sb-ligands. 5 crystallizes in the space group Pn3 with two formula units per unit cell. The lattice constants at 200 K are: a = b = c = 1 995.4(2) pm. 相似文献
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Synthesis, Crystal Structure, Vibrational Spectra, and Normal Coordinate Analysis of [Co(NH3)6][Os(SCN)6] From the mixture of the linkage isomers [Os(NCS)n(SCN)6–n]3–, n = 0–2, pure [Os(SCN)6]3– has been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of [Co(NH3)6][Os(SCN)6] (trigonal, space group R 3, a = 12.368(2), c = 11.830(2) Å, Z = 3) reveals that the thiocyanate ligands are exclusively S‐coordinated with the Os–S distance of 2.388 Å and the Os–S–C angle of 108.8°. The IR and Raman spectra of (n‐Bu4N)3[Os(SCN)6] are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constant fd(OsS) is 1.42 mdyn/Å. 相似文献
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《Journal of organometallic chemistry》1987,328(3):C25-C28
Low yields of the ionic carbene complexes [Ir(RCNHMe)Cl(CO)(PPh3)2-(O3SCF3)]O3SCF3]O3SCF3 (R Ph or PhCH2) have been isolated from the reactions of trans-[IrCl(CO)(PPh3)2] with the nitrilium triflate salts, [RCNMe]O3SCF3. The major products from these, and the similar reactions of the nitrilium salts where R Me or But, are amorphous, yellow complexes [Ir(RCNHMe)Cl(CO)(PPh3)2O3SCF3. 相似文献
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Preparation, Structures, and Properties of Tris-hexamethyl-trisila-tetraphospha-nortricyclene-bis-chromiumtricarbonyl [P4(Sime2)3]3[Cr(CO)3]2 Hexamethyl-trisila-tetraphospha-nortricyclene P4(Sime2)3 1 reacts with C6H6Cr(CO)3 or (CHT)Cr(CO)3 (CHT ? Cycloheptatriene) under formation of [P4(Sime2)3]3[Cr(CO)3]2 3 (red crystals), in which each of the Cr atoms is attached to one P atom of a P3 ring of the three molecules 1 . 3 can also be prepared by heating a solution of P4(Sime2)3Cr(CO)5 in benzene or THF up to 120–1307deg;C. The compound 3 crystallizes in an orthorhombic and a hexagonal form, the latter being stabilized by one mole toluene. As revealed by single crystal investigations, the symmetry ¯6, distances and angles are nearly unchanged. The o-form corresponds to a face centered cubic packing of the molecules, whereas the h-form is hexagonal close packed. 相似文献
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Reaction of C(NMe2)4 with Ni(CO)4 – Syntheses and Structures of [C(NMe2)3][(CO)3NiC(O)NMe2], [C(NMe2)3]2[Ni5(CO)12], and [C(NMe2)3]3[Ni6(CO)12][O2CNMe2] The reaction of C(NMe2)4 with Ni(CO)4 in THF produces the carbamoyl complex [C(NMe2)3][(CO)3NiC(O)NMe2] ( 1 ); side products are the purple cluster compound [C(NMe2)3]2[Ni5(CO)12] · THF ( 2 · THF) and the red cocristallization product [C(NMe2)3]3[Ni6(CO)12][O2CNMe2] ( 3 ). All compounds were studied by X‐ray diffraction analyses. The cations of 3 are all disordered but not those of 1 and 2 . The unit cell of 1 contains two crystallographically independent anions (I and II) which differ in the dihedral angle between the plane of the carbamoyl ligand and the plane defined by the atoms CCarbamoyl–Ni–CO amounting 0° in the anion I and 18° in the anion II. 相似文献
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Syntheses and Crystal Structure Analyses of [SbI3(SbMe3)(THF)]2 and [Li(THF)4]2[Bi2Cl8(THF)2] The reaction of Me3Sb with SbI3 in tetrahydrofuran (THF) gives [SbI3(SbMe3)(THF)]2 ( 1 ). [Li(THF)4]2[Bi2Cl8(THF)2] ( 2 ) is formed by reaction of LiCl and BiCl3 in tetrahydrofuran. The structures of ( 1 ) and ( 2 ) have been determined by X-ray diffractometry. Both structures contain centrosymmetric dimers with the geometry of edge sharing octahedra. 相似文献
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Synthesis and Crystal Structures of (PPh4)2[In(S4)(S6)Cl] and (PPh4)2[In(S4)Cl3] InCl and PPh4Cl yield (PPh4)2[In2Cl6] in acetonitrile. This reacts with Na2S4 in presence of PPh4Cl, forming (PPh4)2[In(S4)(S6)Cl]. Its crystal structure was determined by X-ray diffraction (R = 0.075, 2 282 observed reflexions). It is isotypic with (PPh4)2[In(S4)(S6)Br] and contains anions with trigonal-bipyramidal coordination of In, Cl occupying an axial position, and the S4 and S6 groups being bonded in a chelate manner. The reaction of (PPh4)2[In2Cl6] and sulfur in acetonitrile yielded (PPh4)2[InCl5] and (PPh4)2[In(S4)Cl3]. The crystal structure analysis of the latter (R = 0.072, 4 080 reflexions) revealed an anion with distorted trigonal-bipyramidal coordination of In, the S4 group occupying one axial and one equatorial position; the S4 group shows positional disorder. 相似文献
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Mono- and Binuclear Dinitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of (PPh3Me)2[WCl4(NO)2], (PPh3Me)2[MoCl3(NO)2]2, and (PPh3Me)2[WCl3(NO)2]2 The complexes (PPh3Me)2[MCl4(NO)2] (M = Mo, W), and (PPh3Me)2[MCl3(NO)2]2, respectively, are prepared by reactions of the polymeric compounds MCl2(NO)2 with triphenylmethylphosphonium chloride in CH2Cl2, forming green crystals. According to the IR spectra the nitrosyl groups are in cis-position in all cases. The tungsten compounds as well as (PPh3Me)2[MoCl3(NO)2]2 were characterized by structure determinations with X-ray methods. (PPh3Me)2[WCl4(NO)2]: space group C2/c, Z = 4. a = 1874, b = 1046, c = 2263 pm, β = 119.99°. Structure determination with 3492 independent reflexions, R = 0.057. The compound consists of PPh3Me⊕ ions, and anions [WCl4(NO)2]2? with the nitrosyl groups in cis-position (symmetry C2v). (PPh3Me)2[WCl3(NO)2]2: Space group C2/c, Z = 4. Structure determination with 2947 independent reflexions, R = 0.059. (PPH3Me)2[MoCl3(NO)2]2: Space group P1 , Z = 1. a = 989, b = 1134, c = 1186 pm; α = 63.25°, β = 80.69°, γ = 69.94°. Structure determination with 3326 independent reflexions, R = 0.046. The compounds consist of PPh3Me⊕ ions, and centrosymmetric anions [MCl3(NO)2]22?, in which the metal atoms are associated via MCl2M bridges of slightly different lengths. One of the NO groups is in an axial position, the other one in equatorial position (symmetry C2h). 相似文献
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Reaction between Os[B(OEt)2]Cl(CO)(PPh3)2 and 1,2-ethanediol in the presence of Me3SiCl (1 equivalent) leads to the tethered boryl complex, Cl(CO)(PPh3)2 (1), in which one ethoxy substituent on the boryl ligand is exchanged with one hydroxy group of the 1,2-ethanediol leaving the other OH group available to coordinate to osmium, so giving a six coordinate complex. This formulation is confirmed by crystal structure determination. The same reactants, but with 2 equivalents of Me3SiCl, lead to the yellow, coordinatively unsaturated complex, OsCl(CO)(PPh3)2 (2). Complex (2) adds CO to give OsCl(CO)2 (PPh3)2 (3). Crystal structure determinations of 2 and 3 reveal a very marked difference in the Os-B distances found in the five coordinate complex 2 (2.043(4) Å) and the six coordinate complex 3 (2.179(7) Å). In a reaction similar to that used for forming 2 but with 1,3-propanediol replacing 1,2-ethanediol, the product is OsCl(CO)(PPh3)2 (4). The crystal structure for 4 is also reported. 相似文献
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Syntheses and Structures of (Et4N)2[Re(CO)3(NCS)3] and (Et4N)[Re(CO)2Br4] Rhenium(I) and rhenium(III) carbonyl complexes can easily be prepared by ligand exchange reactions starting from (Et4N)2[Re(CO)3Br3]. Using nonoxidizing reagents the facial ReI(CO)3 unit remains and only the bromo ligands are exchanged. Following this procedure, (Et4N)2[Re(CO)3(NCS)3] can be obtained in high yield and purity using trimethylsilylisothiocyanate. The compound crystallizes in the monoclinic space group P21/n, a = 18.442(5), b = 17.724(3), c = 18.668(5) Å, β = 92.54(1)°, Z = 8. The NCS? ligands are coordinated via nitrogen. The reaction of [Re(CO)3Br3]2? with Br2 yields the rhenium(III) anion [Re(CO)2Br4]?. The tetraethylammonium salt of this complex crystallizes in the noncentrosymmetric, orthorhombic space group Cmc21, a = 8.311(1), b = 25.480(6), c = 8.624(1) Å, Z = 4. The carbonyl ligands are positioned in a cis arrangement. Their strong trans influence causes a lengthening of the Re? Br bond distances by at least 0.05 Å. 相似文献
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Synthesis and Crystal Structures of (PPh4)2[TeS3] · 2 CH3CN and (PPh4)2[Te(S5)2] (PPh4)2[TeS3] · 2 CH3CN was obtained by the reaction of PPh4Cl, Na2S4 and Te in acetonitrile. With sulfur it reacts yielding (PPh4)2[Te(S5)2]. The crystal structures of both products were determined by X-ray diffraction. (PPh4)2[TeS3] · 2 CH3CN: triclinic, space group P1 , Z = 2, R = 0.041 for 4 629 reflexions; it contains trigonal-pyramidal [TeS3]2? ions with an average Te? S bond length of 233 pm. (PPh3)2[Te(S5)2]: monoclinic, P21/n, Z = 2, R = 0.037 for 2 341 reflexions. In the [Te(S5)2]2? ion the tellurium atom has a nearly square coordination by four S atoms. Along with the Te atoms each of the two S5 groups forms a ring with chair conformation. 相似文献