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1.
Mixed Crystals from A4B3 Molecules (A = P, As; B = S, Se) The system P4S3? P4Se3? As4S3? As4Se3 was investigated by thermal and x-ray methods. Five regions of solid solubility with different crystal structures were found at room temperature. The range of existence can be influenced by the temperature of annealing. All these phases transform into a plastic-crystalline modification with complete solid solubility at higher temperature. A decomposition reaction of the A4B3 molecules was observed in the P4Se3/As4Se3/As4S3 part of the system. The molecules decompose into A4B4 molecules and an amorphous phase. The existence of all molecules of the type PnAs4–nSmSe3–m (n = 0–4, m = 0–3) and also As4SmSe4–m (m = 1–3) was verified by mass spectrometric measurements. The thermochemical data of the mixed crystals are determined by the type of the constituent A4B3 molecules. The temperature and the entropy of the α–β transition are lower for mixed crystals, formed by substituted molecules, than for those of the same structure, consisting of pure A4B3 molecules.  相似文献   

2.
This paper reports on the gas‐phase radical–radical dynamics of the reaction of ground‐state atomic oxygen [O(3P), from the photodissociation of NO2] with secondary isopropyl radicals [(CH3)2CH, from the supersonic flash pyrolysis of isopropyl bromide]. The major reaction channel, O(3P)+(CH3)2CH→C3H6 (propene)+OH, is examined by high‐resolution laser‐induced fluorescence spectroscopy in crossed‐beam configuration. Population analysis shows bimodal nascent rotational distributions of OH (X2Π) products with low‐ and high‐N′′ components in a ratio of 1.25:1. No significant spin–orbit or Λ‐doublet propensities are exhibited in the ground vibrational state. Ab initio computations at the CBS‐QB3 theory level and comparison with prior theory show that the statistical method is not suitable for describing the main reaction channel at the molecular level. Two competing mechanisms are predicted to exist on the lowest doublet potential‐energy surface: direct abstraction, giving the dominant low‐N′′ components, and formation of short‐lived addition complexes that result in hot rotational distributions, giving the high‐N′′ components. The observed competing mechanisms contrast with previous bulk kinetic experiments conducted in a fast‐flow system with photoionization mass spectrometry, which suggested a single abstraction pathway. In addition, comparison of the reactions of O(3P) with primary and tertiary hydrocarbon radicals allows molecular‐level discussion of the reactivity and mechanism of the title reaction.  相似文献   

3.
Formation and Structure of iso-Tetraphosphane P[P(SiMe3)Me]3 The reaction of MeP(SiMe3)2 with PCl3 (molar ratio 3:1, ?78°C, n-pentane) yields by cleaving of the P? Si bond P[P(SiMe3)Me]3 1 with Cl2P? P(SiMe3)Me and ClP[P(SiMe3)Me]2 as intermediates. The reaction rate decreases by the increase of phosphorylation. The last reaction step (formation of 1 ) occurs while warming up to room temperature. 1 forms colorless hexagonal crystals, melting point 65 ± 1°C. Tris(trimethylsilyl-methyl-phosphino)phosphane 1 crystallizes monoclinically in the space group Cc (No. 8) with Z = 8 formula units per unit cell. The molecules possess approximated C3 symmetry and have (RRR) and (SSS) configurations, respectively. The bond distances d?(P? P) = 220.1 pm, d?(P? C) = 186.5 pm, and d?(P? Si) = 225.2 pm are normal and within the expected range of known distances. According to repulsive interactions between the non bonded electron pairs of the terminal P atoms and the protons of the methyl groups the angles at the central and terminal P atoms are enlarged to ? P P P = 105.1° and ? P P C = 106.9°, respectively.  相似文献   

4.
Formation and Reactions of the CH2Li‐Derivatives of tBu2P–P=P(CH3)tBu2 and (Me3Si)tBuP–P=P(CH3)tBu2 With nBuLi, (Me3Si)tBuP–P=P(CH3)tBu2 ( 1 ) and tBu2P–P=P(CH3)tBu2 ( 2 ) yield (Me3Si)tBuP–P=P(CH2Li)tBu2 ( 3 ) and tBu2P–P=P(CH2Li)tBu2 ( 4 ), wich react with Me3SiCl to give (Me3Si)tBuP–P=P(CH2–SiMe3)tBu2 ( 5 ) and tBu2P–P=P(CH2–SiMe3)tBu2 ( 6 ), respectively. With tBu2P–P(SiMe3)–PtBuCl ( 7 ), compound 3 forms 5 as well as the cyclic products [H2C–P(tBu)2=P–P(tBu)–PtBu] ( 8 ) and [H2C–P(tBu)2=P–P(PtBu2)–P(tBu)] ( 9 ). Also 3 forms 8 with tBuPCl2. The cleavage of the Me3Si–P‐bond in 1 by means of C2Cl6 or N‐bromo‐succinimide yields (Cl)tBuP–P=P(CH3)tBu2 ( 10 ) or (Br)tBuP–P=P(CH3)tBu2 ( 11 ), resp. With LiP(SiMe3)2, 10 forms (Me3Si)2P–P(tBu)–P=P(CH3)tBu2 ( 12 ), and Et2P–P(tBu)–P=P(CH3)tBu2 ( 13 ) with LiPEt2. All compounds are characterized by 31P NMR Data and mass spectra; the ylide 5 and the THF adduct of 4 additionally by X‐ray structure analyses.  相似文献   

5.
The reaction of cyclo ‐P4Mes4C(NCy) ( 1 ) with two equivalents of [AuCl(tht)] (tht=tetrahydrothiophene) resulted in the formation of unusual sixteen‐membered Au–P macrocycle 2 . This macrocycle contains diphospha(III)guanidinate as a coordinating ligand, which is formed by P−P bond cleavage of 1 . Macrocycle 2 was characterized by multinuclear NMR spectroscopy, mass spectrometry and X‐ray crystallography.  相似文献   

6.
Reaction of elemental antimony with sulfur under mild hydrothermal conditions yielded different polysulfido-clusters of antimony. These were isolated as tetraphenylphosphonium salts [P(C6H5)4]3Sb3S25 and [P(C6H5)4]2Sb2S15 · 2(C3N2H6) and their crystal structures were determined. In the first compound two different polysulfide anions are observed, Sb2S172– and Sb2S162–, whereas the second contains the Sb2S152– complex. These dinuclear anions show as a common building principle two ψ-trigonal bipyramidal coordinated Sb centers bridged by two Sx2– units and an additional Sx2– chelate ligand bound to each Sb center giving a tricyclic structure.  相似文献   

7.
Abstract

The reaction of 1-naphthylamine with one equivalent of chlorodiphenylphosphine in the presence of triethylamine gave the (1-NHC10H7)PPh2 (1) ligand. Refluxing of 1 with elemental sulfur or grey selenium in toluene (1:1 molar ratio) afforded (1-NHC10H7)P(S)Ph2 (2) and (1-NHC10H7)P(Se)Ph2 (3), respectively. Moreover, the byproduct {Ph2P(S)}2O (4) was isolated from the reaction of 1 with elemental sulfur. Compounds 13 were identified and characterized by multinuclear (1H, 13C, 31P, 77Se) NMR spectroscopy, mass spectrometry, and elemental analysis. Crystal structure determinations of 3 and 4 were carried out.  相似文献   

8.
The new cyclic phosph(V)azane ligand [(C6H5N)P(O)H]2 (2) is obtained from the reaction between PCl3 and PhNH2 in toluene followed by controlled hydrolysis of the product in an H2O–CHCl3 solution. Compound 2 is the first example of P(V) dimer [(µ-NC6H5)P(H)=O]2, a P2N2 ring with two P(O)H moieties. The reaction of 2 with ZnCl2 in a molar ratio of 1?:?1 in tetrahydrofuran yields the cyclophosph(V)azane complex Cl2Zn[(C6H5N)P(O)H]2 (3) in which Zn–O bonds form directly between a cyclic phosph(V)azane ligand and Zn(II). The products have been characterized by infrared, multinuclear (1H, 31P, 13C) NMR, mass spectrometry, and elemental analysis.  相似文献   

9.
Metal Sulfur-Nitrogen Compounds. 19. Novel Complexes of CuI with the S3N? Chelate Ligand. Preparation and Structure of [Ph4As][Cu(S3N)(CN)], [(Ph3P)2N][Cu(S3N)(S7N)], and [Ph4As]2[(S3N)Cu(S2O3)Cu(S3N)] In alkaline media S7NH reacts with Cu salts to yield different products. With Cu(CN) the ion [Cu(S3N)(CN)]? is formed, which was isolated as the [Ph4As]+ salt. The crystals are monoclinic, space group P21/c, a = 10.499(5), b = 13.418(6), c = 18.032(8) Å, β = 91.84°(3), Z = 4. Besides the known complex ions [Cu(S3N)2]? and [Cu(S3N)Cl]? still some more may be obtained when CuCl2 is reacted with S7NH: Under special conditions the S7N ring is partly preserved, and [Cu(S3N)(S7N)]? is formed. Its sparingly soluble [(Ph3P)2N]+ salt is monoclinic, space group P21/n, a = 9.335(6), b = 30.984(11), c = 15.108(8) Å, β = 102.87°(4), Z = 4. Using a longer reaction time a dinuclear complex [(S3N)Cu(S2O3)Cu(S3N)]? ? results from the reaction of CuCl2 with S7NH. The two Cu atoms are bridged by an S atom of the S2O3? ? anion. The [Ph4As]+ salt of the dinuclear complex anion is triclinic, space group P1 , a = 11.226(6), b = 12.423(6), c = 19.000(10) Å, β = 76.47°(4), β = 83.98°(4), γ = 84.71°(4), Z = 2. In all these compounds the coordination of CuI is trigonal-planar, the S3N? chelate group coordinates the Cu in the usual way by two S atoms.  相似文献   

10.
Hexamethyl-trisila-tetraphospha-nortricyclene, P4 Sime23 Reaction of white phosphorus with Na/K alloy and subsequent treatment with me2SiCl2 (me = CH3) yields crystalline P4(Sime2)3 (m. p. 159–160°C) along with polymeric silylphosphanes. The structure is derived from 31P-n.m.r.and mass spectra and turns out to be analogous to P4S3.  相似文献   

11.
The reaction of [VO(OPr)3] with (iso-PrO)2P(S)SH (Pr is n-propyl, and iso-Pr is isopropyl) followed by the treatment with hexamethyldisilthiane (Me3SiSSiMe3) affords the vanadium(III) dithiophosphate complex [V(S2P(O-iso-Pr)2)3]. The structure of the complex is determined by X-ray diffraction analysis (CIF file CCDC 986354).  相似文献   

12.
本文用量子化学密度泛函方法对C3H2 (环丙烯基自由基)与O(3P)反应的机理进行了理论研究。在B3LYP/6-311++G**计算水平上优化了各驻点(过渡态,中间体,产物)的几何结构,在QCISD(T)/6-311++G**水平下计算了各物质的单点能量,在两种水平下计算了298K和600K时的能量。计算结果表明:C3H2 + O(3P) 反应可以生成P1 (C2H +HCO),P2 (C2H2 + CO) 和P3 (HC3O+H)三种产物。生成P1反应通道的能垒最低,即P1为主要产物,与实验的结果一致。产物P1可以通过路径:R→ IM1→ IM2→ P1获得。本文详细地讨论了C3H2 + O(3P) 的反应机理,并从理论上对实验结果进行了验证。研究结果有助于深入理解C3H2 + O(3P)反应机理以及C3H2在大气中的燃烧过程。  相似文献   

13.
Pale blue, lath‐shaped single crystals of K2NdP2S7 (≡ K4Nd2[PS4]2[P2S6]; monoclinic, P21/n, a = 904.76(8), b = 677.38(6), c = 1988.7(2) pm, β = 97.295(5)°, Z = 2) are obtained by the reaction of Nd, S and P2S5 with an excess of KCl as a flux in evacuated silica tubes at 750 °C (7 d) which should produce Nd[PS4] instead. Beside isolated [PS4]3– tetrahedra, the crystal structure contains discrete ethane‐analogous [P2S6]4– (≡ [S3P–PS3]4–) units in staggered conformation with tetravalent phosphorus cations and a P–P distance of 219 pm. The two crystallographically different potassium cations show coordination numbers of nine and ten in the shape of distorted mono‐ and bicapped square antiprisms. Finally, the Nd3+ cations are surrounded by eight sulfur atoms arranged as (uncapped) square antiprisms. The entire structure is dominated by (K1)+ containing {(Nd2[PS4]2[P2S6])4–} layers parallel (101) which are three‐dimensionally interconnected by (K2)+ cations.  相似文献   

14.
Near C 3 symmetry is displayed by the 19-atom In-P polyhedron that forms the central structural unit in the title compound (see structure), which was synthesized by reaction of InCl3 with PEt3 and PhP(SiMe3)2. In addition to In–P bonds, the cage has In–In and P–P bonds. Six terminal chloro ligands and three PEt3 ligands surround the cluster core which itself encloses a central chloride anion.  相似文献   

15.
Synthesis, NMR Spectra and Structure of [(CH3)2Ga{μ‐P(H)Si(CH3)3}2Ga(CH3)2{μ‐P(Si(CH3)3)2}Ga(CH3)2] The title compound has been prepared in good yield by the reaction of [Me2GaOMe]3 (Me = CH3) with HP(SiMe3)2 in toluene (ratio 1 : 1,1) and purified by crystallization from pentane or toluene, respectively. This organogallium compound forms (Ga–P)3 ring skeletons with one Ga–P(SiMe3)2–Ga and two Ga–P(H)SiMe3–Ga bridges and crystallizes in the monoclinic space group C2/c. The known homologous Al‐compound is isotypic, both (MIII–P)3 heterocycles have twist‐conformations, the ligands of the monophosphane bridges have trans arrangements.  相似文献   

16.
The Unusual Transformation of P(SnMe3)3 to P4(SnMe2)6 The stannylated phosphine P(SnMe3)3 reacts in the presence of small amounts of [(ZnCl)2Fe(CO)4(THF)2] in THF (tetrahydrofurane) at room temperature forming insoluble P4(SnMe2)6 ( 1 ). This compound crystallizes as colourless needles directly from the reaction mixture (space group Cmcm, a = 1593.6(3) pm, b = 1118.2(2), c = 1602.5(3), Z = 4). Reaction of ZnCl2 with P(SnMe3)3 under the same reaction conditions leads to the complex [ZnCl2{P(SnMe3)3}THF] ( 2 ) (space group Pccn, a = 1593, 6(3) pm, b = 1118, 2(2), c = 1602, 5(3), Z = 8.  相似文献   

17.
A novel discrete [Ag21{S2P(OiPr)2}12](PF6) nanocluster has been synthesized and characterized by single‐crystal X‐ray diffraction and also NMR spectroscopy (1H, 31P), ESI mass spectrometry, and other analytic techniques (XPS, EDS, UV/Vis spectroscopy). The Ag21 skeleton has an unprecedented silver‐centered icosahedron that is capped by eight additional metal atoms. The whole framework is protected by twelve dithiophosphate ligands. According to the spherical Jellium model, the stability of monocationic nanocluster can be described by an 8‐electron superatom with 1S2 1P6 configuration, as confirmed by DFT calculations.  相似文献   

18.
The reaction paths of thiosulfeno radical (HS2) with O(3P) have been investigated at the UB3LYP/aug-cc-pV(T + d)Z and UCCSD(T)/aug-cc-pV(T + d)Z//B3LYP levels. Two stable collision intermediates, HSSO and SS(H)O, have been considered for the HS2 + O(3P) reaction. Four products of S + HSO, H + SSO, HS + SO, and S2 + OH are obtained by starting from HSSO and SS(H)O. The calculated results show that the most feasible paths for the formation of S + HSO, H + SSO, and HS + SO products include no transition states in reaction path, while that of S2 + OH product includes relatively high energy barriers of 23.0 kcal/mol. Therefore, S + HSO, H + SSO, and HS + SO are main products (with the stability other of HS + SO > H + SSO > S + HSO) and S2 + OH is the second product in HS2 + O(3P) reaction. Because, all intermediates, transition states, and products involved in the reaction paths lie below the initial reactants, the HS2 + O(3P) reaction is expected to be rapid even at low temperatures.  相似文献   

19.
The undecanuclear copper cluster Cu11(μ9‐Se)(μ3‐I)3[Se2P(OEt)2]6 1 , has been isolated along with Cu88‐Se)[Se2P(OEt)2]6 2 , from the reaction of NH4Se2P(OEt)2, Cu(CH3CN)4PF6, and Bu4NI in a molar ratio of 3:2:2 in diethyl ether. The molecular formulation of 1 was confirmed by elemental analysis, positive FAB mass spectrometry, multinuclear NMR (1H, 31P, and 77Se), and X‐ray diffraction. In cluster 1 eleven copper atoms adopt the geometry of a 3,3,4,4,4‐pentacapped trigonal prism with a selenium atom in the center. The coordination geometry for the central, nonacoordinated selenium atom is tricapped trigonal prismatic. In addition, the central core Cu11Se is further stabilized by three iodides and six dsep ligands. Besides, weak inter‐molecular Se···I interactions (3.949–3.972 Å) are uncovered and form a one dimensional polymeric chain.  相似文献   

20.
Two novel heterometallic cubane-like and double cubane-like clusters, {MoCu3S3(S2COEt)}(O)(Ph3P)3 I and {Mo2Cu6S6(SCMe3)2}(O)2(Ph3P)4 II, were synthesized by reaction of {MoCu2S3}(O)(Ph3P)3 with CuS2COEt and CuSCMe3, respectively. ClusterI crystallized in the triclinic space group (2) witha=12.766(6) Å,b=22.904(5) Å,c=10.522(3) Å, =99.86(2)°, =109.68(2)°, =86.84(3)°,V=2854(2) Å3,Z=2,R=0.049 for 6622 observed reflections (I>5(I)) and 410 variables. ClusterII crystallized in the triclinic space group (2) with dimensionsa=14.212(4) Å,b=14.725(5) Å,c=12.396(8) Å, =110.32(4)°, =90.40(5)°, =62.88(2)°,V=2129(2) Å3,Z=1,R=0.039 for 6020 observed reflections (I>3(I)) and 461 variables. ClusterI consists of a neutral cubane-like molecule with the core {MoCu3S3(S2COEt)}2+, in which one corner of the cubane-like core is a novel triply bridging bidentate 1,1-dithiolato (xanthate, S2COEt) ligand. ClusterII is a double cubane-like one, in which two cubane-like cores {MoCu3S3(SCMe3)}2+ are connected by two Cu-S bonds of the triply bridging monothiolato (SCMe 3 ) ligand. Two different pathways of unit construction from a small heterometallic cluster {MoCu2S3}(O)(Ph3P)3 have been outlined. Comparisons of the selected bond lengths and bond angles for the cubane-like core {MoCu3S3 X} (X=Cl, Br, S2COEt, SCMe 3 ) are given. Spectroscopic properties of the title clusters are also reported.  相似文献   

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