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1.
Chloroselenates(IV): Synthesis, Structure, and Properties of [As(C6H5)4]2Se2Cl10 and [As(C6H5)4]Se2Cl9 The Se2Cl102? and Se2Cl9? anions were prepared, as the first dinuclear haloselenates(IV), from the reaction of (SeCl4)4 with stoichiometric quantities of chloride ions in POCl3 solutions; they were isolated as yellow crystalline As(C6H5)4+ salts. Complete X-ray structural analyses at ?130°C of [As(C6H5)4]2Se2Cl10 ( 1 ) (space group P1 , a = 10.296(7), b = 11.271(6), c = 12.375(8) Å, = 74.17(5)°, α = 81.38(5)°, β = 67.69(4)°, V = 1276 Å3) and of [As(C6H5)4]Se2Cl9 ( 2 ) (space group P21/n, a = 12.397(5), b = 17.492(6), c = 14.235(4) Å, α 93.25(3)°, V = 3082 Å3) show in both cases two distorted octahedral SeCl6 groups connected through a common edge in 1 and a common face in 2 . The terminal Se? Cl bonds (average 2.317 Å in 1 , 2.223 Å in 2 ) are much shorter than the Se? Cl bridges (av. 2.661 Å in 1 , 2.652 Å in 2 ). The stereochemical activity of the SeIV lone electron pair causes severe distortion of the central Se2Cl2 ring in the centrosymmetric Se2Cl102? ion. The vibrational spectra of the anions are reported.  相似文献   

2.
Solvothermal reaction of [MnCl2(amine)] (amine = terpy and tren) with elemental As and Se at a 1:1:2 molar ratio in H2O/tren (10:1) affords the dimanganese(II) complexes [{Mn(terpy)}2(μ‐As2Se4)] ( 1 ) and [{Mn(tren)}2(μ‐As2Se5)] ( 2 ) respectively. The tetradentate [As2Se4]4? bridging ligands in 1 contain a central As–As bond and exhibit approximately C2h symmetry. Pairs of gauche sited Se atoms participate in five‐membered As2Se2Mn chelate rings. In contrast, two AsSe3 pyramids share a common corner in the [As2Se5]4? ligands of 2 and each coordinates an [Mn(tren)]2+ fragment through a single terminal Se atom. Such dinuclear complexes are linked into tetranuclear moieties through weak Se···Mn interactions of length 3.026(3) Å involving one of these terminal Se atoms. At a 1:3:6 molar ratio, solvothermal reaction of [MnCl2(tren)] with As and Se leads to formation of a second dinuclear complex [{Mn(tren)}2(μ‐As2Se6)2] ( 3 ), which contains two bridging bidentate [As2Se6]2? ligands. These are cyclic with an As2Se4 ring and can be regarded as being derived from [As2Se5]4? anions by formation of two Se‐Se bonds to an additional Se atom.  相似文献   

3.
Synthesis and Crystal Structures of (PPh4)2[As2Se4Cl12] and (PPh4)2[As2Se4Br12] The reaction of PPh4Cl and As2Se3 with SOCl2 or with chlorine in dichloromethane affords (PPh4)2[As2Se4Cl12] with good yields. From PPh4Br, As2Se3 and bromine the corresponding bromo compound was obtained. According to the X-ray crystal structure determinations both compounds are isotypic, crystallizing in the space group of P1 . In the anions two Se2X2 molecules are linked with two X? ions forming an Se4X2 ring in chair conformation. Each X?-ion is associated with an additional AsX3 molecule (X = Cl, Br).  相似文献   

4.
Cyclic Polyselenidoarsenates(III) and Polyselenidoantimonates(III): PPh4[Se5AsSe], PPh4[AsSe6–xS x ], (PPh4)2[As2Se6] · 2 CH3CN, and (PPh4)2[Se6SbSe]2 In acetonitrile, AsCl3 and sodiumphenolate formed Cl2AsOPh which then was reacted with PPh4Se5 and finally with Na2Se to yield PPh4[Se5AsSe]. With Na2S instead of Na2Se, PPh4[AsSe6–xSx] was obtained; the sulfur contents increased with increasing reaction temperature and time (x = 0.21 to 1.09). With PPh4Se2 instead of PPh4Se5, (PPh4)2[1,4-As2Se6] · 2 CH3CN and PPh4[Se5AsSe] were the products. With SbCl3 instead of AsCl3, (PPh4)2[Se6SbSe]2 formed. PPh4[Se5AsSe] can also be produced from As2Se3, PPh4Br, Na2Se and selenium in acetonitrile. The crystal structure of PPh4[SeAsSe5] is isotypic with PPh4[S5AsS] (X-ray structure analysis with 2414 observed reflexions, R = 0.038). The Se5AsSe ion consists of a six-membered AsSe5 ring in chair conformation, and the As atom has an additional terminal Se atom. The compounds PPh4[AsSe6–xSx] have the same crystal structures, with sulfur atoms taking all selenium positions at random, but with a preference for the terminal position. The anion in (PPh4)2[As2Se6] · 2 CH3CN also has a six-membered ring structure in chair conformation, with two arsenic atoms in positions 1 and 4. The centrosymmetric anion in (PPh4)2[Se6SbSe]2 consists of a central Sb2Se2 ring, and a Se6 ligand is bonded in a chelating manner to each Sb atom (X-ray structure analysis with 2669 observed reflexions, R = 0.099). 77Se-NMR spectra are reported.  相似文献   

5.
Methanolothermal reaction of [MnCl3(9‐ane‐N3)] with As2Se3 at 150 °C in the presence of Cs2CO3 affords violet‐coloured [Mn(9‐ane‐N3)2]As6Se5 ( 1 ). Its novel tricyclic selenidoarsenate(I,II) anion [As6Se5]2? contains two five‐membered [As3As(Se)Se] rings that are symmetry‐related by a crystallographic C2 axis passing through the common AsI‐AsI bond between their respective first two ring members. The adjacent AsI atoms in the individual rings are bridged by the Se atom of the third [As4Se] ring.  相似文献   

6.
CASSCF–MRMP2 calculations have been carried out to analyze the reactions of the methyl fluoride molecule with the atomic ions Ge+, As+, Se+ and Sb+. For these interactions, potential energy curves for the low‐lying electronic states were calculated for different approaching modes of the fragments. Particularly, those channels leading to C? H and C? F oxidative addition products, H2FC? M? H+ and H3C? M? F+, respectively were explored, as well as the paths which evolve to the abstraction (M? F++CH3) and the elimination (CH2M++HF) asymptotes. For the reaction Ge++CH3F the only favorable channel leads to fluorine abstraction by the ion. As+ and Sb+ can react with CH3F along pathways yielding stable addition products. However, a viable path joining the oxidative addition product H3C? M? F+ with the elimination asymptote CH2M++HF was found for the reaction of the fluorocarbon compound with As+. No favorable channels were detected for the interaction of fluoromethane with Se+. The results discussed herein allow rationalizing some of the experimental data found for these interactions through gas‐phase mass spectrometry.  相似文献   

7.
Asymmetric ditertiary stibine sulfides (C6H5)(CH3)(S)SbCH2Sb(CH3)(C6H5) and [(C6H5)(CH3)(S)Sb]2(CH2)3 have been prepared. It was found that they exist as only one of two possible diastereomers in the crystalline state. However, isomerization to the other form takes place in solution, resulting in an equilibrium mixture. A possibility of configurational lability of tertiary stibine sulfide was suggested for the first time.  相似文献   

8.
As12Se44—: a New Selenoarsenate Anion with a Polyarsenic Cage in the Compound [Co(NH3)6]2As12Se4 · 12 NH3 Orange coloured crystals of [Co(NH3)6]2As12Se4 · 12 NH3 were prepared by the reduction of As4Se4 with a solution of sodium in liquid ammonia and subsequent precipitation with CoBr2. The X‐ray structure determination shows them to contain the selenoarsenate anion As12Se44—, which consists of a central As12‐cage with four exo‐bonded, formally negatively charged Se atoms. The structure of the As12‐cage is equivalent to the main polyphosphorus building unit of a known organopolyphosphane and of tubular P12 in the compound (CuI)3P12.  相似文献   

9.
Thiochloroarsenates (III): Preparation, Vibrational Spectra, and Crystal Structures of PPh4[As2SCl5] and (PPh4)2[As2SCl6] · C2H4Cl2 PPh4[As2SCl5] can be obtained from As2S3 + PPh4Cl with HCl in CH2Cl2 or 1,2-C2H4Cl2. It reacts with a second mole of PPh4Cl to yield (PPh4)2[As2SCl6]. The latter also is formed by the reaction of As2S5 + 2 PPh4Cl with HCl, a second product being (PPh4)2[As2Cl8]. The i.r. and Raman spectra of the title compounds are reported. Their crystal structures were determined by X-ray diffraction. Crystal data: PPh4[As2SCl5], monoclinic, space group P21/n, a = 1175.8, b = 1508.0, c = 1593.4 pm, β = 96.22°, Z = 4; (PPh4)2[As2SCl6] · C2H4Cl2, triclinic, P1, a = 1166.3, b = 1188.2, c = 2044.6 pm, α = 95.47, β = 97.53, γ = 111.05°, Z = 2. Including the lone electron pairs, the coordination of the As atoms in the [As2SCl5] ion is distorted trigonal-bipyramidal with the S, one Cl atom, and an electron pair in equatorial positions; the two bipyramids around the two As atoms share a common edge. The As atoms in the [As2SCl6]2− ion have a distorted octahedral coordination, the two octahedra share a common face; the lone electron pairs are in the trans positions to the S atom.  相似文献   

10.
In comparison with other chalcogenide glassy systems, less attention has been paid to the quasi-ternary (quaternary) system As2(S, Se, Te)3. In this paper, thermal methods were used to characterize ten different quaternary homogenous semiconductor glasses that were prepared by mixing the stoichiometric binary systems As2S3, As2Se3 and As2Te3. The ratios of the constituent binaries in the quasi-ternary glasses exerted a great influence on their thermal spectrum. The samples poor in As2Te3 showed neither the exothermic nor the endothermic peak due to crystallízation (T c) and melting (T m), respectively, but only the glass transition (T g). Three transition temperatures,T g, Tc andT m, were detected for other compositions. On the other hand, a phase separation was observed in the samples rich in As2Te3. A cyclic scanning technique was used to investigate the thermally-induced phases during two consecutive heat ing-cooling cycles covering the temperature rangeT g?Tm. The energy of decompositionE d decreased on increase of the ratio As2S3/As2Se3 (at constant As2Te3), whereas it increased on increase of the ratio As2Te3/As2Se3 (at constant As2Se3 or As2S3).  相似文献   

11.
Studies of Polyhalides. 22. On Dimethyldiphenylammoniumpolyiodides (Me2Ph2N)In with n = 3, 13/3, 6, and 8: Preparation and Crystal Structures of a Triiodide (Me2Ph2N)I3, Tridecaiodide (Me2Ph2N)3I13, Dodecaiodide (Me2Ph2N)2I12, and Hexadecaiodide (Me2Ph2N)2I16 The new compounds [(CH3)2(C6H5)2N]I3, [(CH3)2(C6H5)2N]3I13, [(CH3)2(C6H5)2N]2I12 and [(CH3)2(C6H5)2N]2I16 have been prepared by the reaction of dimethyldiphenylammonium iodide [(CH3)2(C6H5)2N]I with iodine I2 in ethanol. Their crystal structures have been determined by single crystal X-ray diffraction methods. The structure of the triiodide may be described as a layerlike packing of pairs of nearly linear symmetric anions and tetraedral cations. The tridecaiodide forms zig-zag chains of iodide ions and iodine molecules with the iodide ion also weakly coordinated by two pentaiodide groups. The dodecaiodide is built from two pentaiodide-groups, which are bridged by an iodine molecule and connected with secondary bonds forming double chains. The hexadecaiodide ion forms layers built up from two heptaiodide groups and one iodine molecule. Thus the dimethyldiphenylammonium cation stabilizes a unique series of polyiodides of extraordinary composition and structure.  相似文献   

12.
Whereas (CH3)3Si? P(C2H5)2 does not react with LiP(C2H5)2 (I), there are reactions of SiH-containing silylphosphines with one P(C2H5)2 group as well as of SiH- and Simethylated silylphosphines with (I), yielding phosphorylated products and LiH according to equ. (1) (2). SiH-containing Silylphosphines, being Si? CH3-free and having more than one P(C2H5)2-group, such as HSi[P(C2H5)2]3, react with LiP(C2H5)2 by exchange of Li for H, acc. to equ.(3). With (CH3)3SiCl, LiSi[P(C2H5)2]3 yields (CH3)3Si? Si[P(C2H5)2]3 and with SiH3Br H3Si? Si[P(C2H5)2]3. There is a cleavage of the Si? P bond with Li-CH3 or n? LiC4H9. The reaction starts as shown in equ. (4), yielding (CH3)3SiH and (CH3)3Si? P(C2H5)2 as intermediate products and finally (CH3)4Si (equ. 5).  相似文献   

13.
Xenon trioxide (XeO3) forms adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone by coordination of the ligand oxygen atoms to the XeVI atom of XeO3. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction, and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, solid (C5H5NO)3(XeO3)2, [(C6H5)3PO]2XeO3, and [(CH3)2SO]3(XeO3)2 are insensitive to mechanical shock. The [(CH3)2SO]3(XeO3)2 adduct slowly decomposes over several days to (CH3)2SO2, Xe, and O2. All three complexes undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are room-temperature stable and the [(CH3)2CO]3XeO3 complex dissociates at room temperature to form a stable solution of XeO3 in acetone. The xenon coordination sphere of [(C6H5)3PO]2XeO3, a distorted square-pyramid, provides the first example of a five-coordinate XeO3 complex with only two Xe- - -O adduct bonds. The xenon coordination spheres of the remaining adducts are distorted octahedra, comprised of three Xe- - -O secondary bonds that are approximately trans to the primary Xe−O bonds of XeO3. Quantum-chemical calculations were used to assess the nature of the Xe- - -O adduct bonds, which are described as predominantly electrostatic bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the electrophilic xenon atoms.  相似文献   

14.
Solvothermal reaction of [MnCl2(terpy)] with elemental As and Se at a 1:1:2 molar ratio in H2O/trien (10:1) at 150 °C affords the linear trimanganese(II) complex [{Mn(terpy)}3(μ‐AsSe4)2] ( 1 ). The tridentate [AsSe2(Se2)]3? anions of 1 chelate the terminal {Mn(terpy)}2+ fragments and bridge these through their remaining Se atom to the central {Mn(terpy)}2+ moiety. Weak interactions of Mn1···Se and Mn3···Se bonds with length 2.914(7) and 3.000(7) Å link the molecules of 1 into infinite chains. Treatment of [MnCl2(cyclam)]Cl with As and Se at a 1:1:2 molar ratio in superheated H2O/CH3OH (1:1) at 150 °C yields the dinuclear complex [{Mn(cyclam)}2 (μ‐As2Se6)] ( 2 ), whose novel [(AsSe2)2(μ‐Se2)]4? ligands bridge the MnII atoms in a μ‐1κ2Se1, Se2: 2κ2Se5,Se6 manner.  相似文献   

15.
Vibrational Spectra of As4S4 and As4Se4 The vibrational spectra of solid α- and β-As4S4 and the Raman spectrum of molten As4S4 have been recorded. The assignments of the frequencies are proposed mainly based on polarization data. The Raman melt spectra suggest that As4S4 molecules (symmetry D2d) are retained in the molten state. A partial decomposition of the melt by prolonged laser irradiation was observed. The Raman spectrum of solid As4Se4 is presented and the frequencies are tentatively assigned to an As4Se4 molecule of the cradle type, possessing D2d symmetry.  相似文献   

16.
Studies on Selenium Compounds. LXIV. Preparation and Properties of Acid Derivatives of Phenylselenium(IV) Compounds (C6H5) 2SeX2 and (C6H5) 3SeX. Reactions of (C6H5) 2SeBr2 and (C6H5) 3SeCl with silver salts of acids are investigated. From (C6H5) 2SeBr3 and AgY (Y = N03, CH3CO3, CF3CO2, 1/2 SO4, CH3SO3, NCO) the compounds (C6H5) 2Se(NO3) 2 (C6H5) 2Se(CH3CO2) 2, (C6Hs) 2Se(CF3CO2) 2, (C6H5) 2SeSO4, (C6H5) 2Se(CH3SO3) 2 and (C6H5) 2Se(NCO) 2 are prepared. They are characterized by solubility, molecular weight and conductivity. Reaction of (C6H5) 3SeCl and AgX (X = NO3, CH3CO2) yields (C6H5) 3SeNO3 and (C6H5) 3SeCH3CO2.  相似文献   

17.
Iridium(I) and Iridium(III) Complexes with Triisopropylarsane as Ligand The ethene complex trans‐[IrCl(C2H4)(AsiPr3)2] ( 2 ), which was prepared from [IrCl(C2H4)2]2 and AsiPr3, reacted with CO and Ph2CN2 by displacement of ethene to yield the substitution products trans‐[IrCl(L)(AsiPr3)2] ( 3 : L = CO; 4 : L = N2). UV irradiation of 2 in the presence of acetonitrile gave via intramolecular oxidative addition the hydrido(vinyl)iridium(III) compound [IrHCl(CH=CH2)(CH3CN)(AsiPr3)2] ( 5 ). The reaction of 2 with dihydrogen led under argon to the formation of the octahedral complex [IrH2Cl(C2H4)(AsiPr3)2] ( 7 ), whereas from 2 under 1 bar H2 the ethene‐free compound [IrH2Cl(AsiPr3)2] ( 6 ) was generated. Complex 6 reacted with ethene to afford 7 and with pyridine to give [IrH2Cl(py)(AsiPr3)2] ( 8 ). The mixed arsane(phosphane)iridium(I) compound [IrCl(C2H4)(PiPr3)(AsiPr3)] ( 11 ) was prepared either from the dinuclear complex [IrCl(C2H4)(PiPr3)]2 ( 9 ) and AsiPr3 or by ligand exchange from [IrCl(C2H4)(PiPr3)(SbiPr3)] ( 10 ) und triisopropylarsane. The molecular structure of 5 was determined by X‐ray crystallography.  相似文献   

18.
Contributions to the Chemistry of Phosphorus. 67. About the Cyclotriphosphanes (PC6H5)3, (PC6H5)2(PC2H5), and (PC6H5)2(PCH3) The reaction of (CH3)3Si(C6H5)P? P(C6H5)Si(CH3)3 with RPCl2 (R = C6H5, C2H5, CH3) yields the cyclotriphosphanes (PC6H5)3 1 , (PC6H5)2(PC2H5) 3 , and (PC6H5)2(PCH3) 4 , respectively. Besides, the corresponding homo- and mixed-substituted cyclotetraphosphanes, cyclopentaphosphanes, and cyclohexaphosphanes are formed. The relative concentrations of the cyclotriphosphanes in the reaction mixtures decrease continuously, whereas those of the cyclopentaphosphanes increase. The reasons for these ring-interconversion reactions of the cyclophosphanes (PR)n are discussed. The cyclotriphosphanes 1, 3 , and 4 are characterized by 31P chemical shifts between +130 and +160 ppm that are at considerable high field compared to open-chain triphosphanes and cyclophosphanes of different ring-size. The substituents R are situated on both sides of the P3-ring plane, thus giving rise to two diastereomers of 3 that are observed simultaneously in the statistically expected ratio. The 31P n.m.r. parameters of 1 and 3 are reported and discussed.  相似文献   

19.
C5H5Co(PMe3)2 (I) reacts with CSSe to give C5H5Co(η2-CSSe)PMe3 (IV) and C5H5Co(CS)PMe3 (V). The thiocarbonyl complex V is formed in an almost quantitative yield by Se abstraction from IV and PPh3. The corresponding compounds C5H5Co(CS)PMe2Ph (VII) and C5H5Co(CS)[P(OMe)3] (VIII) are obtained as the main products directly from CSSe and C5H5Co(PMe2Ph)2 or C5H5Co[P(OMe)3]2. In the reaction of C5H5Co(PR3)2 (PR3 = PMe3, PMe2Ph) with CSe2, the carbon diselenide complexes C5H5Co(η2-CSe2)PMe3 (XI) and C5H5Co(η2-CSe2)PMe2Ph (XIV) are formed. XI reacts with PPh3 to give C5H5Co(CSe)PMe3 (XII). Cyclopentadienylcobalt compounds containing CSSe22?, CSe32? and C2Se42? as ligands are isolated as side products in the; reactions of C5H5Co(PR3)2 and C5H5Co(CO)PR3 (PR3 = PMe3, PMe2Ph) with CSSe and CSe2, respectively. Displacement of ethylene from C5H5Rh(C2H4)PMe3 by CSSe yields the complex C5H5Rh(η2-CSSe)PMe3 (XVIII) which reacts with PPh3 to give C5H5Rh(CS)PMe3 (XIX) and with excess CSSe to give C5H5RhC2S2Se2(PMe3) (XX). Besides small amounts of C5H5Rh(η2CSSe)PMe2Ph (XXI), the corresponding metallaheterocycle C5H5RhC2S2Se2(PMe2Ph) (XXII) is formed as the main product from C5H5Rh(C2H4)PMe2Ph and CSSe.  相似文献   

20.
Some new N‐4‐Fluorobenzoyl phosphoric triamides with formula 4‐F‐C6H4C(O)N(H)P(O)X2, X = NH‐C(CH3)3 ( 1 ), NH‐CH2‐CH=CH2 ( 2 ), NH‐CH2C6H5 ( 3 ), N(CH3)(C6H5) ( 4 ), NH‐CH(CH3)(C6H5) ( 5 ) were synthesized and characterized by 1H, 13C, 31P NMR, IR and Mass spectroscopy and elemental analysis. The structures of compounds 1 , 3 and 4 were investigated by X‐ray crystallography. The P=O and C=O bonds in these compounds are anti. Compounds 1 and 3 form one dimensional polymeric chain produced by intra‐ and intermolecular ‐P=O···H‐N‐ hydrogen bonds. Compound 4 forms only a centrosymmetric dimer in the crystalline lattice via two equal ‐P=O···H‐N‐ hydrogen bonds. 1H and 13C NMR spectra show two series of signals for the two amine groups in compound 1 . This is also observed for the two α‐methylbenzylamine groups in 5 due to the presence of chiral carbon atom in molecule. 13C NMR spectrum of compound 4 shows that 2J(P,Caliphatic) coupling constant for CH2 group is greater than for CH3 in agreement with our previous study. Mass spectra of compounds 1 ‐ 3 (containing 4‐F‐C6H4C(O)N(H)P(O) moiety) indicate the fragments of amidophosphoric acid and 4‐F‐C6H4CN+ that formed in a pseudo McLafferty rearrangement pathway. Also, the fragments of aliphatic amines have high intensity in mass spectra.  相似文献   

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