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1.
Contributions to the Chemistry of Phosphorus. 225. Lithium Pentahydrogen Octaphosphide Lithium pentahydrogen octaphosphide, LiH5P8 ( 1 ), belongs to the first reaction products of the metallation of P2H4 with n-butyllithium to be detected. Compound 1 is also formed in the reactions of the tricyclic heptaphosphide Li3P7 or the monocyclic pentaphosphide LiH4P5 with P2H4. In all cases, LiH4P7, LiH8P7, and further not yet identified polyphosphides are formed additionally. The composition and the structure of 1 have been elucidated by 31P-NMR studies, above all a complete analysis of its low-temperature 31P{1H}-NMR spectrum. Hence, compound 1 is 7-lithium-2,5,6-trihydrogen-3-phosphino-bicyclo[2.2.1]heptaphosphide and has a norbornane-type P7 skeleton. At room temperature 1 decomposes to furnish more phosphorus-rich lithium polyphosphides. 相似文献
2.
Contributions to the Chemistry of Phosphorus. 140. Dilithium Hydrogen Heptaphosphide, Li2HP7 — a Partially Metallated Derivative of P7H3: Preparation and Structural. Characterization Dilithium hydrogen heptaphosphide, Li2HP7 ( 2 ), is purely obtained as an orange-red solvent adduct by reacting P2H4 with n-BuLi or Li3P7 ( 1 ) under suitable conditions. 2 is also formed in the metalation of LiH2P7 ( 3 ) or P7H3, in the disproportionation of LiH4P5, in thepartial protolysis of 1 , and in the nucleophilic cleavage of P4. The composition and the structure of 2 could be elucidated by a complete analysis of its low-temperature 31P{1H}-NMR spectrum. As shown by the δ(31P) values, the P7 cage in 2 is clearly distorted compared with 1 . The P7H2? ion has fluctuating bonds in analogy to dihydrobullvalene and can be described by two valence-tautomeric forms with identical structures. At room temperature 2 disproportionates yielding lithium polyphosphides with a greater number of phosphorus atoms. 相似文献
3.
Contributions to the Chemistry of Phosphorus. 151. Dilithium Dihydrogen Tetradecaphosphide, Li2H2P14: Preparation and Structural Characterization Dilithium dihydrogentetradecaphosphide, Li2H2P14 ( 1 ), is obtained as an orange-red solvent adduct Li2H2P14 · 6 THF in a purity of 80–90 per cent by reacting P2H4 with n-BuLi under suitable conditions. 1 is also formed in the reaction of Li3P7 or LiH4P5 with P2H4, and in the disproportionation of LiH4P7. According to its 2D-31P-NMR spectrum 1 is a conjuncto-phosphane built up by one P7(5)?- and one P9(3)?-unit group with structures analogous to norbornane and delta-cyclane, respectively. 相似文献
4.
Chemistry and Structural Chemistry of Phosphides and Ployphosphides. 44. Tricesium Heptaphosphide Cs3P7: Preparation, Structure, and Properties Tricesium heptaphosphide is prepared from the elements by a quantitative reaction at 1200 K in Nb ampoules. Slow cooling yield the bright yellow α-Cs3P7, quenching the yellow orange coloured β-Cs3P7. The crystalline α-Cs3P7 transforms at 552 K in a first order phase transition to the plastically crystalline β-Cs3P7. Both modifications are sensitive against moisture and oxygen and are completely soluble in ethylendiamine yielding a pale yellow solution. At room temperature the 31P nmr spectra of such solutions show only one singulett, which corresponds to the valence tautomerism of the P73? anion. α-Cs3P7 crystallizes in a new structure type (P41, a = 904.6(1) pm; c = 1671.4(4) pm; Z = 4). The structure is formed by heptaphospha-nortricyclene anions P73? and Cs+ cations. The cs atoms connect the anions forming a three-dimensional arrangement (d?(Cs? P) = 374 pm), not allowing the fragmentation into discrete Cs3P7 units. The P? P distances differ by their function in the nortricyclene anion. Each P7 group is surrounded by 12 Cs atms. β-Cs3P7 crystallizes in the Li3Bi type of structure (Fm3 M; a(573 K) = 1130.5(1)pm; Z = 4). The P atoms of the P73? anions surround the Bi positions with an orienational disorder. The orientation has been investigated with a mixed crystal Ca3(P7)2/3(P11)1/2 (Fm3 m; a (298 K) = 1149.5(9) pm; Z = 4). 相似文献
5.
Contributions to the Chemistry of Phosphorus. 167. Constitutional and Configurational Isomers of Pentaphosphane(7), P5H7 Phosphane mixtures containing 10—15 P-% of pentaphosphane(7), P5H7, are obtained by thermolysis of diphosphane, P2H4, or as residue from distillation of crude diphosphane [3]. According to the complete analysis of the 31P{1H}-NMR spectrum on the basis of selective population transfer experiments, P5H7 exists as a mixture of three diastereomers of n-P5H7 — 1a (erythro, erythro), 1b (erythro, threo), 1c (threo, threo) — and of the constitutional isomer 2-phosphinotetraphosphane 2 (iso-P5H7, largest relative isomeric abundance). The correlation between the diastereomers and the observed spin systems results from the preferred gauche orientation of neighboring free electron pairs, the dependence of 1J(PP) on dihedral angles, and the 3J(PP) long range couplings. From the 31P-NMR data of the phosphane molecules PnHn+2 with n = 1—5 general relationships for the δ(31P) values and the 1J(PP) coupling constants of chain-type phosphorus hydrides as a function of their structural parameters are derived. 相似文献
6.
A series of high‐spin clusters containing Li, H, and Be in which the valence shell molecular orbitals (MOs) are occupied by a single electron has been characterized using ab initio and density functional theory (DFT) calculations. A first type (5Li2, n+1LiHn+ (n = 2–5), 8Li2H) possesses only one electron pair in the lowest MO, with bond energies of ~3 kcal/mol. In a second type, all the MOs are singly occupied, which results in highly excited species that nevertheless constitute a marked minimum on their potential energy surface (PES). Thus, it is possible to design a larger panel of structures (8LiBe, 7Li2, 8Li, 4LiH+, 6BeH, n+3LiH (n = 3, 4), n+2LiH (n = 4–6), 8Li2H, 9Li2H, 22Li3Be3 and 22Li6H), single‐electron equivalent to doublet “classical” molecules ranging from CO to C6H6. The geometrical structure is studied in relation to the valence shell single‐electron repulsion (VSEPR) theory and the electron localization function (ELF) is analyzed, revealing a striking similarity with the corresponding structure having paired electrons. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
7.
Thermal Dehydration of Lithium Dihydrogenphosphate, -Hydrogen-diphosphate, and -Cyclophosphate Hydrates On heating lithium dihydrogenphosphate, LiH2PO4, is converted to lithium polyphosphate, (LiPO3)n · H2O [2–5]. Seeding LiH2PO4 with lithium cyclohexaphosphate, Li6P6O18, the thermal dehydration proceeds structurally controlled to pure Li6P6O18. On heating lithium hydrogen-diphosphate, Li3HP2O7, reacts to Li4P2O7 form III and lithium cyclotetraphosphate, Li4P4O12 form II , which ist converted to Li6P6O18 at higher temperatures. The thermal dehydration of Li2H2P2O7 and of the cyclophosphate hydrates Li3P3O9 · 3 H2O, Li4P4O12 · (8 and 6) H2O, Li6P6O18 · (6 and 4) H2O and Li8P8O24 · (10 and 6) H2O are described. 相似文献
8.
Dmitry Yu. Naumov Marina I. Naumova Nina V. Podberezskaya Natalia V. Kuratieva 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(8):i73-i75
The structures of monoclinic (C2/m) lithium dihydrogenphosphate, LiH2PO2, and tetragonal (P41212) beryllium bis(dihydrogenphosphate), Be(H2PO2)2, have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of hypophosphite anions and metal cations in tetrahedral coordination by O atoms. Within the layers, the anions bridge four Li+ and two Be2+ cations, respectively. In LiH2PO2, the Li atom lies on a twofold axis and the H2PO2− anion has the PO2 atoms on a mirror plane. In Be(H2PO2)2, the Be atom lies on a twofold axis and the H2PO2− anion is in a general position. 相似文献
9.
Contributions to the Chemistry of Phosphorus. 171. 31P-N.M.R. Spectroscopic Detection of Heptaphosphane(9), P7H9: erythro- and threo-2,3-Diphosphinopentaphosphane Small amounts of heptaphosphane(9), P7H9, could be detected 31P-NMR spectroscopically in mixtures of higher phosphanes PnHn+2 which are obtained as residue from distillation of crude diphosphane [2] or by thermolysis of P2H4. According to the results of a spectrum analysis on the basis of selective population transfer experiments, the heptaphosphane(9) in question is one of the possible constitutional isomers with maximum branching, namely 2,3-diphosphinopentaphosphane ( 4 ), which is present in the erythro and threo from 4a and 4b , respectively. The correlation between the diastereomers and the observed spin systems results from the determination of the corresponding molecular conformation by means of significant 1J(PP) and 3J(PP) coupling constants. 4 is the first structurally characterized compound with seven chain-like connected phosphorus atoms. 相似文献
10.
M. Baudler J. Dobbers Ch. P. Schner M. Borgardt D. Rackwitz U. M. Krause 《无机化学与普通化学杂志》1995,621(9):1459-1465
Contributions to the Chemistry of Phosphorus. 236. On Several Physical and Chemical Properties of Diphosphane(4) The density of diphosphane(4) has been measured between ?78°C and +18°C and the value d420 = 1.014 · 0.002 extrapolated. The refractive index of P2H4 was determined to be n20 = 1.66 ± 0.01. The surface tension at 0°C and ?50°C was measured to be σ = 34 and 42 dyn · cm?1, respectively. In the UV absorption spectrum, gaseous P2H4 exhibits a broad absorption band at λmax = 2 220 Å, in n-hexane solution, this band is shifted somewhat to shorter wave-lengths. The molar extinction coefficient was determined to be ? ≈? 900 1 · mol?1 · cm?1. As a result of photolytic decomposition, absorptions for PH3 and more phosphorus-rich hydrides also occur. The solubility behavior of P2H4 in various organic solvents and the stabilities of the resultant solutions have been investigated. At 0°C, the solubility of diphosphane(4) in water was found to be ± 035 ± 0.003 g P2H4/100 g solution and that of water in diphosphane(4) to be 43.2 ± 1.6 g H2O/100 g solution. The system diphosphane(4)/methanol also exhibits a miscibility anomaly. The IR spectra of liquid P2H4 and of its solutions in various solvents revealed, in accord with the results of nuclear magnetic resonance spectroscopy [7], that diphosphane(4) is practically not associated. Weak interactions through hydrogen bridging bonds occur with pyridine and methanol in which P2H4 serves as the proton donor and, in the latter case, also as proton acceptor. For the thermolysis of diphosphane(4), it has been found that the primary step comprises a disproportionation with inter-molecular elimination of PH3 and formation of triphosphane(5). With further progress of the thermolysis, in dependence on the reaction conditions, mixtures of various phosphanes of differing composition are formed. Photolysis gives rise to phosphane mixtures having similar compositions. With aqueous silver salt and iodine solutions, diphosphane(4) reacts as a reducing agent; with sodium hydroxide solution, it reacts by a slow disproportionation as well as by formation and degradation of the subsequently formed polyphosphides. On reaction with triphenylmethyl, triphenylmethane and a yellow solid of varying composition are formed. The reaction of diazomethane with diphosphane(4) leads to the preferential insertion of the carbene in the P? P bond and formation of methylenebis(phosphane). 相似文献
11.
The system (LiH2)? has been investigated for several nuclear positions, taking all six electrons into account, using the Allgemeines Programmsystem/SCF ? MO ? LC (LCGO ) Methode. A metastable molecule was found having a linear configuration (RLiH = 3.5 ± 0.2 a.u.) and a total energy 0.12 a.u. lower than that of the separated atoms. On the other hand, (LiH2)? can dissociate into Li? + H2; the total energy of which is 0.01 a.u. smaller. The potential barrier for this process is found to be 0.15 a.u. The energy hypersurface is given graphically and the formation (as well as the decomposition) of (LiH2)? is discussed. 相似文献
12.
Dr. Darius J. Yeadon Dr. Johan Jacquemin Dr. Natalia V. Plechkova Dr. Manuel Maréchal Prof. Kenneth R. Seddon 《Chemphyschem》2020,21(13):1369-1374
The interactions between aprotonic tetrabutylphosphonium carboxylate ionic liquids (ILs), [P4 4 4 4][CnCOO] (n=1, 2 and 7), and water were investigated. The cation-anion interactions occur via the α-1H on [P4 4 4 4]+ and the carboxylate headgroup of the anion. Upon addition, H2O localises around the carboxylate headgroups, inducing an electron inductive effect towards the oxygens, leading to ion-pair separation. Studies with D2O and [P4 4 4 4][CnCOO] revealed protic behaviour of the systems, with proton/deuterium exchange occurring at the α-1H of the cation, promoted by the basicity of the anion, forming an intermediate ylide. The greater influence of van der Waals forces of the [P4 4 4 4][C7COO] system allows for re-orientation of the ions through larger interdigitation. The protic behaviour of the neat ILs allows for CO2 to be chemically absorbed on the ylide intermediate, forming a phosphonium-carboxylate zwitterion, signifying proton exchange occurs even in the absence of H2O. The absorption of CO2 in equimolar IL-H2O mixtures forms a hydrogen carbonate, through a proposed reaction of the CO2 with an intermediate hydroxide, and carboxylic acid. 相似文献
13.
Synthesis and Crystal Structure of the Lithium Strontium Hydride Nitride LiSr2H2N LiSr2H2N was synthesized by the reaction of LiH and Li3N with elemental strontium in sealed tantalum tubes at 650 °C within seven days. This second example of a quaternary hydride nitride crystallizes orthorhombically in space group Pnma (no. 62) with the lattice constants a = 747.14(5) pm, b = 370.28(3) pm and c = 1329.86(9) pm (Z = 4). Its crystal structure contains both kinds of anions H? and N3? in a sixfold distorted octahedral metal cation coordination each. The coordination polyhedra [(H1)Sr5Li]10+, trans‐[(H2)Sr4Li2]9+ and [NSr5Li]8+ are connected via edges and corners to form a three‐dimensional network. Two crystallographically different Sr2+ cations exhibit a sevenfold monocapped trigonal prismatic coordination by H? and N3? with [(Sr1)H5N2]9? and [(Sr2)H4N3]11? polyhedra, wheras Li+ shows a nearly planar fourfold coordinative environment ([LiH3N]5?). Cationic double chains of edge‐shared [NSr5Li]8+ octahedra dominate the structure according to . Running parallel to the [0 1 0] direction, they are bundled like a hexagonal rod‐packing which is interconnected by H? anions within the (0 0 1) plane first and finally even in the third dimension (i. e. along [0 0 1]). Therefore the structure of LiSr2H2N is compared to that one of the closely related quaternary hydride oxide LiLa2HO3. 相似文献
14.
This paper reports our results for the direct experimental determination of the equilibrium constant for the hydrogen-isotope-exchange
reaction, 1/2D2(g)+HCl(hexOH)=1/2H2(g)+DCl(hexOD), where hexOH isn-hexanol and hexOD isn-hexanol with deuterium substitution in the alcohol function. The reaction was studied in electrochemical double cells without
liquid junction for which the net cell reaction is the above isotope-exchange reaction. The experimentally determined value
of ε° (296.0°K) for this cell is 4.03±0.95 mV (strong electrolyte standard states, mole-fraction composition scale); the value
of the equilibrium constant for the reaction is 1.17±0.05. The contributions of isotope-exchange and transfer effects to the
magnitude of the standard Gibbs energy change for the above reaction and for the analogous reaction 1/2D2(g)+HCl(aq)=DCl(daq)+1/2H2(g) are considered. Our results support the conclusion of Heinzinger and Weston that the formulation of the solvated proton
in water as H3O+, as opposed to H9O4
+, is sufficient for the interpretation of the thermodynamics of hydrogen-isotope-exchange reactions in water. We also find
that the formulation of the solvated proton inn-hexanol as ROH
2
+
is sufficient for the interpretation of our results on the thermodynamics of hydrogen-isotope-exchange inn-hexanol. 相似文献
15.
Syntheses and Structures of Trilithium Cyclotriphosphazenates Equipped with 2‐Halo‐aryl Substituents
Hexakis (2‐halo‐anilino) cyclotriphosphazenes (2‐X‐C6H4NH)6P3N3 {X = F ( 1d ), Cl ( 1e ), Br ( 1f )} were prepared by refluxing mixtures of hexachloro cyclotriphosphazene, 2‐haloaniline and triethylamine in toluene and characterized by single crystal X‐ray diffraction. 1d , 1e and 1f were reacted with nBuLi in thf. Reactions were monitored with 31P NMR. Addition of three equivalents of nBuLi yields lithium complexes of trianionic phosphazenates [{(thf)2Li}3{(2‐X‐C6H4N)3(2‐X‐C6H4NH)3P3N3}] {X= F ( 2d ), Cl ( 2e ) and Br ( 2f )}. 2d , 2e and 2f were structurally characterized by X‐ray diffraction, which reveals monomeric cis‐metalated phosphazenates featuring central P3N3 ring systems of chair conformation. Lithium ions reside in three N(eq)‐P‐N(endo) chelation sites at one face of the P3N3 ring system. Li…X distances are rather long (> 3Å) indicating no Li‐X interactions. 相似文献
16.
Six mono/double‐layered 2D and three 3D coordination polymers were synthesized by a self‐assembly reaction of Zn (II) salts, organic dicarboxylic acids and L1/L2 ligands. These polymeric formulas are named as [Zn(L1)(C4H2O4)0.5 (H2O)]n·0.5n(C4H2O4)·2nH2O ( 1 ), [Zn2(L2)(C4H2O4)2]n·2nH2O ( 2 ), [Zn(L1)(m‐BDC)]n ( 3 ), [Zn2(L2)(m‐BDC)2]n·2nH2O ( 4 ), [Zn3(L1)2(p‐BDC)3(H2O)4]n·2nH2O ( 5 ), [Zn2(OH)(L2) (p‐BDC)1.5]n ( 6 ), [Zn2(L1)(p‐BDC)2]n·5nH2O ( 7 ), [Zn2(L2)(p‐BDC)2]n·3nH2O ( 8 ) and [Zn2(L1)(C4H4O4)1.5(H2O)]n·n(ClO4)·nH2O ( 9 ) [L1 = N,N′‐bis (pyridin‐4‐ylmethyl)propane‐1,2‐diamine, L2 = N,N′‐bis (pyridin‐3‐ylmethyl)propane‐1,2‐ diamine, m‐BDC2? = m‐benzene dicarboxylate, p‐BDC2? = p‐benzene dicarboxylate]. Meanwhile, these polymers have been characterized by elemental analysis, infrared, thermogravimetry (TG), photoluminescence, powder and single‐crystal X‐ray diffraction. Polymers 1–6 present mono‐ and double (4,4)‐layer motifs accomplished by L1/L2 ligands with diverse conformations and organic dicarboxylates, and the layer thickness locates in the range of 5.8–15.0 Å. In three 3D polymers, the L1 and L2 molecules adopt the same cis‐conformations and join adjacent Zn (II) cations together with p‐BDC2? or succinate, giving rise to different binodal (4,4)‐c nets with (4.52.83)(4.53.72) ( 7 ), pts ( 8 ) topology and twofold interpenetrated binodal (5,5)‐c nets with (32.44.52.62)(3.43.52.64) ( 9 ). Therefore, the diverse conformations of the two bis (pyridyl)‐propane‐1,2‐diamines and the feature of different organic dicarboxylate can effectively influence the architectures of these polymers. Powder X‐ray diffraction patterns demonstrate that these bulk solid polymers are pure phase. TG analyses indicate that these polymers have certain thermal stability. Luminescent investigation reveals that the emission maximum of these polymers varies from 402 to 449 nm in the solid state at room temperature. Moreover, 1 , 3 and 5–8 show average luminescence lifetimes from 8.81 to 16.30 ns. 相似文献
17.
The mechanism of propene elimination from metastable methyleneimmonium ions is discussed. The first field-free region fragmentations of complete sets of isotopically labelled methyleneimmonium ions (H2C = $ \mathop {\rm N}\limits^{\rm +} $+R1R2: R1 = R2 = n-C3H7; R1 = R2 = i-C3H7; R1 = n -C3H7; R2 = C2H5; R1 = n-C3H7; R2 = CH3; R1 = n-C3H7; R2 = H) were used to support the mechanism presented. The relative amounts of H/D transferred are quantitatively correlated to two distinct mathematical concepts which allow information to be deduced about influences on reaction pathways that cannot be measured directly. Propene loss from the ions examined proceeds via ion-neutral complex intermediates. For the di-n-propyl species rate-determining and H/D distribution-determining steps are clearly distinct Whereas the former corresponds to a 1,2-hydride shift in a 1-propyl cation coordinated to an imine moiety, the latter is equivalent to a proton transfer to the imine occurring from the 2-propyl cation generated by the previous step. For the diisopropyl-substituted ions which directly form the 2-propyl cation-containing complex, the rate-determining hydride shift vanishes. The 2-propyl cation-containing complex can decompose directly or via an intermediate proton-bridged complex. Competition of these routes is not excluded by the experimental results. Assuming a 2:1:3 distribution, a preference for the α- and β-methylene of the initial n-propyl chain as the source of the hydrogen transferred is detected for n-propylimmonium ions containing a second alkyl chain R2. This preference shows a clear dependence on the steric influence of R2. During the transfer step isotopic substitution is found to affect the H/D distribution strongly. For the alternative route of McLafferty rearrangement leading to C2H4 loss, specific γ-H transfer is observed. 相似文献
18.
Heterometallic SrII‐MII (M=Co,Ni, Zn and Cu) Coordination Polymers: Synthesis,Temperature‐Dependent Structural Transformation,and Luminescent and Magnetic Properties
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Dr. Yanmei Chen Qian Gao Wenqian Chen Dr. Dandan Gao Prof. Dr. Yahong Li Dr. Wei Liu Prof. Dr. Wu Li 《化学:亚洲杂志》2015,10(2):411-421
The use of pyridine‐2,4‐dicarboxylic acid (H2pydc) in the construction of SrII and SrII‐MII (M=Co, Ni, Zn and Cu) coordination polymers is reported. Eight complexes, that is, [Sr(pydc)H2O]n ( 1 ), [MSr(pydc)2(H2O)2]n (M=Co ( 2 ), Ni ( 3 ), Zn ( 4 )), [ZnSr(pydc)2(H2O)7]n?4 nH2O ( 5 ), [SrCu(pydc)2]n ( 6 ), [SrCu(pydc)2(H2O)3]n?2 nH2O ( 7 ), and [Cu3Sr2(pydc)4(Hpydc)2(H2O)2]n ( 8 ), have been synthesized via dexterously choosing the appropriate strontium sources and transition metal salts, and rationally controlling the temperature of the reaction systems. Complexes 1 , 2 ( 3 , 4 ), 6 , and 8 display four types of 3‐D framework structures. Complexes 5 and 7 exhibit a 2‐D network and a 1‐D chain structure, respectively. The 2‐D complex 7 can be reversibly transformed into 3‐D compound 6 through temperature‐induced solvent‐mediated structural transformation. The luminescent property studies indicated that complex 1 shows a strong purple luminescent emission and 4 exhibits a strong violet luminescence emission. The magnetic properties of 2 , 3 , and 8 were also studied. Antiferromagnetic MII???MII interactions were determined for these complexes. 相似文献
19.
Contributions to the Chemistry of Phosphorus. 117. Synthesis and Properties of the Hexaorganyl-octaphosphanes(6) P8R6, R = Me, Et, Pri The Hexaorganyl-octaphosphanes(6) P8Me6 ( 1 ), P8Et6 ( 2 ), and P8Pr ( 3 ) have been obtained by reacting mixtures of the corresponding organyldichlorophosphanes and phosphorus(III) chloride with magnesium. In the case of 1 and 2 the organyl-cyclophosphanes (PR)n can also be used in the reaction with phosphorus(III) chloride and magnesium. Besides, mainly P7R5 as well as other polycyclic organylphosphanes are formed. 2 and 3 have been isolated as pure substances, whereas 1 was concentrated to ?50 mol-% in the product mixture. According to their 31P-NMR spectra the three compounds possess a pentalane-analogous P8-skeleton with the substituents within each five-membered ring in trans position and the substituents of different five-membered rings next to the zero bridge in cis position; the organyl groups in the 3, 7 position are trans oriented with respect to the free electron pairs of the bridgehead atoms. Therefore, the structures of 1 – 3 differ from the known tert-butyl compound P8Bu, whereas the corresponding phosphorus hydride P8H6 has the same pentalane-analogous P8-skeleton, thus being a bicyclo[3.3.0]octaphosphane. 相似文献
20.
Dipak Kumar Roy Dr. Shubhankar Kumar Bose K. Geetharani Kiran Kumar Varma Chakrahari Dr. Shaikh M. Mobin Dr. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):9983-9991
The reaction of [CpnMCl4?x] (M=V: n=2, x=2; M=Nb: n=1, x=0; Cp=η5‐C5H5) with LiBH4 ? THF followed by thermolysis in the presence of dichalcogenide ligands E2R2 (E=S, Te; R=2,6‐(tBu)2‐C6H2OH, Ph) and 2‐mercaptobenzothiazole (C7H5NS2) yielded dimetallaheteroboranes [{CpV(μ‐TePh)}2(μ3‐Te)BH ? thf] ( 1 ), [(CpV)2(BH3S)2] ( 2 ), [(CpNb)2B4H10S] ( 3 ), [(CpNb)2B4H11S(tBu)2C6H2OH] ( 4 ), and [(CpNb)2B4H11TePh] ( 5 ). In cluster 1 , the V2BTe atoms define a tetrahedral framework in which the boron atom is linked to a THF molecule. Compound 2 can be described as a dimetallathiaborane that is built from two edge‐fused V2BS tetrahedron clusters. Cluster 3 can be considered as an edge‐fused cluster in which a trigonal‐bipyramidal unit (Nb2B2S) has been fused with a tetrahedral core (Nb2B2) by means of a common Nb2 edge. In addition, thermolysis of an in‐situ‐generated intermediate that was produced from the reaction of [Cp2VCl2] and LiBH4 ? THF with excess BH3 ? THF yielded oxavanadaborane [(CpV)2B3H8(μ3‐OEt)] ( 6 ) and divanadaborane cluster [(CpV)2B5H11] ( 7 ). Cluster 7 exhibits a nido geometry with C2v symmetry and it is isostructural with [(Cp*M)2B5H9+n] (M=Cr, Mo, and W, n=0; M=Ta, n=2; Cp*=η5‐C5Me5). All of these new compounds have been characterized by 1H NMR, 11B NMR, and 13C NMR spectroscopy and elemental analysis and the structural types were established unequivocally by crystallographic analysis of compounds 1 – 4 , 6 , and 7 . 相似文献