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1.
The product from reaction of lanthanum chloride seven-hydrate with salicylic acid and 8-hydroxyquinoline, La(C7H5O3)2·(C9H6NO), was characterized by IR, elemental analysis, molar conductance, and thermogravimetric analysis. The standard molar enthalpies of solution of [LaCl3·7H2O (s)], [2C7H6O3 (s)], [C9H7NO (s)] and [La(C7H5O3)2·(C9H6NO) (s)] in a mixed solvent of absolute ethyl alcohol, dimethyl formamide (DMF) and perchloric acid were determined by calorimetry to be [LaCl3·7H2O (s), 298.15 K] = −96.45 ± 0.18 kJ mol−1, [2C7H6O3 (s), 298.15 K] = 14.99 ± 0.17 kJ mol−1, [C9H7NO (s), 298.15 K] = −3.86 ± 0.06 kJ mol−1 and [La(C7H5O3)2·(C9H6NO) (s), 298.15 K] = −117.78 ± 0.11 kJ mol−1. The enthalpy change of the reaction
(1)  相似文献   

2.
Using an on-line solution-reaction isoperibol calorimeter, the standard molar enthalpies of reaction for the general thermochemical reaction: LnCl3·6H2O(s) + 2C9H7NO(s) + CH3COONa(s) = Ln(C9H6NO)2(C2H3O2)(s) + NaCl(s) + 2HCl(g) + 6H2O(l) (Ln: Nd, Sm), were determined at T=298.15 K, as  kJ mol−l, respectively. From the mentioned standard molar enthalpies of reaction and other auxiliary thermodynamic quantities, the standard molar enthalpies of formation of Ln(C9H6NO)2(C2H3O2)(s) (Ln: Nd, Sm), at T=298.15 K, have been derived to be: −(1494.7±3.3) and −(1501.5±3.4) kJ mol−l, respectively.  相似文献   

3.
Preparation and crystal structure of the novel compound [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 are reported. The title compound is prepared by heating of BiI3 and diethylene glycol at 413 K in a sealed quartz glass tube filled with argon. Deep red single crystals are grown and applied to perform X-ray powder diffraction and X-ray single-crystal diffraction measurements. The compound crystallizes triclinic with space group P-1: Z=2, a=13.217(1) Å, b=15.277(1) Å, c=22.498(1) Å, α=84.33(1), β=73.18(1), γ=67.48(1). [Bi3I(C4H8O3H2)2(C4H8O3H)5]2Bi8I30 comprises the novel polynuclear [Bi8I30]6− anion and [Bi3I(C4H8O3H2)2(C4H8O3H)5]3+ as the cation. Cation as well as the anion can be assumed to represent intermediates between solid BiI3 and BiI3 completely dissolved in diethylene glycol.  相似文献   

4.
The reaction of C5H5Rh(CO)(PiPr3) (1] which is prepared from C5H5Rh(CO)2 and neat P1Pr3, with the nitriloxides 2-RC6H4CNO (R = H, Cl) leads to the formation of the metallaheterocycles C5H5(P1Pr3) ) (2, 3) in 90–95% yield. Compound 1 reacts with tosylazide to give the C,N-bound isocyanate complex C5 H5(PiPr3)Rh(η2-TosN=C=O) (6). Analogously, on treatment of C5Me5Co(CO)(PMe3) with phenylazide the phenylisocyanate derivative C5Me5(PMe3)Co(η2-PhN=C=O) (7) is formed. Protonation of 7 with CF3CO 2H affords the non-ionic carbamoylcobalt complex C5Me5(PMe3)Co[C(O)NHPh](O2CCF3) (8). The X-ray structural analysis of 2 reveals the presence of an almost planar heterocycle in which the two Rh-C distances differ by 0.045 Å  相似文献   

5.
Tren amine cations [(C2H4NH3)3N]3+ and zirconate or tantalate anions adopt a ternary symmetry in two hydrates, [H3tren]2·(ZrF7)2·9H2O and [H3tren]6·(ZrF7)2·(TaOF6)4·3H2O, which crystallise in R32 space group with aH = 8.871 (2) Å, cH = 38.16 (1) Å and aH = 8.758 (2) Å, cH = 30.112 (9) Å, respectively. Similar [H3tren]2·(MX7)2·H2O (M = Zr, Ta; X = F, O) sheets are found in both structures; they are separated by a water layer (Ow(2)-Ow(3)) in [H3tren]2·(ZrF7)2·9H2O. Dehydration of [H3tren]2·(ZrF7)2·9H2O starts at room temperature and ends at 90 °C to give [H3tren]2·(ZrF7)2·H2O. [H3tren]2·(ZrF7)2·H2O layers remain probably unchanged during this dehydration and the existence of one intermediate [H3tren]2·(ZrF7)2·3H2O hydrate is assumed. Ow(1) molecules are tightly hydrogen bonded with -NH3+ groups and decomposition of [H3tren]2·(ZrF7)2·H2O occurs from 210 °C to 500 °C to give successively [H3tren]2·(ZrF6)·(Zr2F12) (285 °C), an intermediate unknown phase (320 °C) and ZrF4.  相似文献   

6.
The metal-metal bonds of the title compounds have been investigated with the help of energy decomposition analysis at the DFT/TZ2P level. In good agreement with experiment, computations yield Hg-Hg bond distance in [H3SiHg-HgSiH3] of 2.706 Å and Zn-Zn bond distance in [(η5-C5Me5)Zn-Zn(η5-C5Me5)] of 2.281 Å. The Cd-Cd bond distances are longer than the Hg-Hg bond distances. Bond dissociation energies (-BDE) for Zn-Zn bonds in zincocene −70.6 kcal/mol in [(η5-C5H5)2Zn2] and −70.3 kcal/mol in [(η5-C5Me5)2Zn2] are greater amongst the compounds under study. In addition, [(η5-C5H5)2M2] is found to have a binding energy slightly larger than those in [(η5-C5Me5)2M2]. The trend of the M-M bond dissociation energy for the substituents R shows for metals the order GeH3 < SiH3 < CH3 < C5Me5 < C5H5. Electrostatic forces between the metals are always attractive and they are strong (−75.8 to −110.5 kcal/mol). The results demonstrate clearly that the atomic partial charges cannot be taken as a measure of the electrostatic interactions between the atoms. The orbital interaction (covalent bonding) ΔEorb is always smaller than the electrostatic attraction ΔEelstat. The M-M bonding in [RM-M-R] (R = CH3, SiH3, GeH3, C5H5, C5Me5; M = Zn, Cd, Hg) has more than half ionic character (56-64%). The values of Pauli repulsions, ΔEPauli, electrostatic interactions, ΔEelstat, and orbital interactions, ΔEelstat are larger for mercury compounds as compared to zinc and cadmium.  相似文献   

7.
Chiral “P-N-P” ligands, (C20H12O2)PN(R)PY2 [R = CHMe2, Y = C6H5 (1), OC6H5 (2), OC6H4-4-Me (3), OC6H4-4-OMe (4) or OC6H4-4-tBu (5)] bearing the axially chiral 1,1′-binaphthyl-2,2′-dioxy moiety have been synthesised. Palladium allyl chemistry of two of these chiral ligands (1 and 2) has been investigated. The structures of isomeric η3-allyl palladium complexes, (R′ = Me or Ph; Y = C6H5 or OC6H5) have been elucidated by high field two-dimensional NMR spectroscopy. The solid state structure of [Pd(η3-1,3-Ph2-C3H3){κ2-(racemic)-(C20H12O2)PN(CHMe2)PPh2}](PF6) has been determined by X-ray crystallography. Preliminary investigations show that the diphosphazanes, 1 and 2 function as efficient auxiliary ligands for catalytic allylic alkylation but give rise to only moderate levels of enantiomeric excess.  相似文献   

8.
C2(a 3πu) disappearance rate constants of 1.44, 0.96, 0.0296, 0.0130 and < 10?6(x10?10cm3s?1) are reported for reactions with C2H4, C2H2, O2, C2H6, and CH4, respectively at 298 K. C2(a 3πu) fragments are generated by multiphoton ArF excimer laser photodissociation at C2H2, and monitored by dye laser induced fluorescence. Arguments are presented which favor chemical reactions over the C2(a 3πu) → (X 1σ+g) quenching channel. C2 + C2H2 represents the one possible exception to the reactive channel.  相似文献   

9.
The thermolysis of [(C5H4)SiMe2(N-t-Bu)]TiPh2 in the presence of diphenylacetylene proceeds at 80 °C in cyclohexane solution with the sole formation of the titanacyclic complex [(C5H4)SiMe2(N-t-Bu)]Ti[(o-C6H4)C(Ph)C(Ph)], which has been characterized by solution NMR measurements and X-ray crystallographic analysis. This reaction is accompanied by the elimination of benzene and presumably occurs via coupling of a titanium benzyne intermediate with diphenylacetylene. The two chemically inequivalent Ti-C bonds of 2.081(7) and 2.103(6) Å in [(C5H4)SiMe2(N-t-Bu)]Ti[(o-C6H4)C(Ph)C(Ph)] reflect the increased electrophilicity of the d0 Ti(IV) center arising from the presence of the bifunctional ansa-cyclopentadienyldimethylsilylamido ligand.  相似文献   

10.
A new open-framework compound, [C6H14N2][(UO2)4(HPO4)2(PO4)2(H2O)]·H2O, (DUP-1) has been synthesized under mild hydrothermal conditions. The resulting structure consists of diprotonated DABCOH22+ (C6H14N22+) cations and occluded water molecules occupying the channels of a complex uranyl phosphate three-dimensional framework. The anionic lattice contains uranophane-like sheets connected by hydrated pentagonal bipyramidal UO7 units. [C6H14N2][(UO2)4(HPO4)2(PO4)2(H2O)]·H2O possesses five crystallographically unique U centers. U(VI) is present here in both six- and seven-coordinate environments. The DABCOH22+ cations are held within the channels by hydrogen bonds to both two uranyl oxygen atoms and a μ2-O atom. Crystallographic data (193 K, Mo Kα, λ=0.71073 Å): DUP-1, monoclinic, P21/n, a=7.017(1) Å, b=21.966(4) Å, c=17.619(3) Å, β=90.198(3)°, Z=4, R(F)=4.76% for 382 parameters with 6615 reflections with I>2σ(I).  相似文献   

11.
The chemical kinetics, studied by UV/Vis, IR and NMR, of the oxidative addition of iodomethane to [Rh((C6H5)COCHCOR)(CO)(PPh3)], with R = (CH2)nCH3, n = 1-3, consists of three consecutive reaction steps that involves isomers of two distinctly different classes of RhIII-alkyl and two distinctly different classes of RhIII-acyl species. Kinetic studies on the first oxidative addition step of [Rh((C6H5)COCHCOR)(CO)(PPh3)] + CH3I to form [Rh((C6H5)COCHCOR)(CH3)(CO)(PPh3)(I)] revealed a second order oxidative addition rate constant approximately 500-600 times faster than that observed for the Monsanto catalyst [Rh(CO)2I2]. The reaction rate of the first oxidative addition step in chloroform was not influenced by the increasing alkyl chain length of the R group on the β-diketonato ligand: k1 = 0.0333 ([Rh((C6H5)COCHCO(CH2CH3))(CO)(PPh3)]), 0.0437 ([Rh((C6H5)COCHCO(CH2CH2CH3))(CO)(PPh3)]) and 0.0354 dmmol−1 s−1 ([Rh((C6H5)COCHCO(CH2CH2CH2CH3))(CO)(PPh3)]). The pKa and keto-enol equilibrium constant, Kc, of the β-diketones (C6H5)COCH2COR, along with apparent group electronegativities, χR of the R group of the β-diketones (C6H5)COCH2COR, give a measurement of the electron donating character of the coordinating β-diketonato ligand: (R, pKa, Kc, χR) = (CH3, 8.70, 12.1, 2.34), (CH2CH3, 9.33, 8.2, 2.31), (CH2CH2CH3, 9.23, 11.5, 2.41) and (CH2CH2CH2CH3, 9.33, 11.6, 2.22).  相似文献   

12.
Two new niobium phosphates were synthesized and their crystal structures determined from single-crystal X-ray data. [NbOF(PO4)](N2C5H7) (1) (monoclinic, space group P21/c, a=11.442(1), b=9.1983(7), c=9.1696(8) Å, β=109.94(1)°) has a layered structure and is the first example of a negatively charged NbOF(PO4) layer analogous to the MO(H2O)PO4 (M=V, Nb) layers. The layer charge is compensated by interlayer 4-aminopyridnium cations that adopt an unusual arrangement as a consequence of H-bonding and π-π interactions. The interlayer aminopyridnium cations can be exchanged with alkylammonium ions which form bilayers inclined at ∼65° to the NbOF(PO4) layer. [(Nb0.9V1.1)O2(PO4)2(H2PO4)] (N2C2H10) (2) (orthorhombic, space group Pbca, a=15.821(2),b=9.0295(9),c=18.301(2) Å) has a disordered three-dimensional structure based on NbO(PO4) layers cross-linked by phosphate tetrahedra, and has a similar structure to the known vanadium analog [V2O2(PO4)2(H2PO4)] (N2C2H10).  相似文献   

13.
Two organically templated zincophosphites, (C6H14N2)·[Zn3(HPO3)4] and (C4H14N2)·[Zn3(HPO3)4] have been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction. (C6H14N2)·[Zn3(HPO3)4] crystallizes in the triclinic space group , with cell parameters, a=9.363(4) Å, b=10.051(4) Å, c=10.051(4) Å, α=85.777(13)°, β=82.091(9)°, and γ=79.783(9)°. (C4H14N2)·[Zn3(HPO3)4] crystallizes in the monoclinic space group P21/c, with cell parameters, a=9.9512(3) Å, b=10.1508(3) Å, c=17.8105(5) Å, and β=95.6510(10)°. Although the two structures are different, they have the same anionic framework compositions of [Zn3(HPO3)4]2−. Their frameworks are built up from strictly alternating ZnO4 tetrahedra and HPO3 pseudo pyramids by sharing vertexes. There exist channels with an eight-membered ring window along the a- and c-axis. Powder X-ray diffraction, IR spectroscopy, 31P MAS solid-state NMR, thermogravimetric and differential thermal analyses were also carried out.  相似文献   

14.
Two hetero-binuclear complexes [CpCoS2C2(B9H10)][Rh(COD)] (2a) and [CpCoSe2C2(B10H10)][Rh(COD)] (2b) [Cp = η5-pentamethylcyclopentadienyl, COD = cyclo-octa-1,5-diene (C8H12)] were synthesized by the reactions of half-sandwich complexes [CpCoE2C2(B10H10)] [E = S (1a), Se (1b)] with low valent transition metal complexes [Rh(COD)(OEt)]2 and [Rh(COD)(OMe)]2. Although the reaction conditions are the same, the structures of two products for dithiolato carborane and diselenolato carborane are different. The cage of the carborane in 2a was opened; However, the carborane cage in 2b was intact. Complexes 2a and 2b have been fully characterized by 1H, 11B NMR and IR spectroscopy, as well as by elemental analyses. The molecular structures of 2a and 2b have been determined by single-crystal X-ray diffraction analyses and strong metal-metal interactions between cobalt and rhodium atoms (2.6260 Å (2a) and 2.7057 Å (2b)) are existent.  相似文献   

15.
The heat capacity of Cr(C5H7O2)3 has been measured by the adiabatic method within the temperature range 5-320 K. An anomaly with a maximum at ∼60 K has been discovered which points to the phase transformation of the compound. Anomalous contributions to entropy and enthalpy have been revealed. The thermodynamic functions (entropy, enthalpy and reduced Gibbs energy) at 298.15 K have been calculated using the obtained experimental heat capacity data. The Raman spectra have been measured in the frequency range 60-400 cm−1 and in the temperature range 5-220 K. It has been discovered that a new line (109 cm−1) appears at ∼60 K. The nature of these peculiarities in heat capacity and in Raman spectra is discussed.  相似文献   

16.
The hydridic reactivity of the complex W(CO)(H)(NO)(PMe3)3 (1) was investigated applying a variety of protic donors. Formation of organyloxide complexes W(CO)(NO)(PMe3)3(OR) (R = C6H5 (2), 3,4,5-Me3C6H2 (3), CF3CH2 (4), C6H5CH2 (5), Me (6) and iPr (7)) and H2 evolution was observed. The reactions of 1 accelerated with increasing acidity of the protic donor: Me2CHOH (pKa = 17) < MeOH (pKa = 15.5) < C6H5CH2OH (pKa = 15) < CF3CH2OH (pKa = 12.4) < C6H2Me3OH (pKa = 10.6) < C6H5OH (pKa = 10).Regioselective hydrogen bonding of 1 was probed with two of the protic donors furnishing equilibrium formation of the dihydrogen bonded complexes ROH···HW(CO)(NO)(PMe3)3 (R = 3,4,5-Me3C6H2,3a and iPr, 7a) and the ONO hydrogen bonded species ROH···ONW(CO)(H)(PMe3)3 (R = C6H2Me3,3b and iPr, 7b) which were studied in hexane and d8-toluene solutions using variable temperature IR and NMR spectroscopy. Quantitative IR experiments at low temperatures using 3,4,5-trimethylphenol (TMP) confirmed the two types of competitive equilibria: dihydrogen bonding to give 3aH1 = −5.8 ± 0.4 kcal/mol and ΔS1 = −15.3 ± 1.4 e.u.) and hydrogen bonding to give 3b (ΔH2 = −2.8 ± 0.1 kcal/mol and ΔS2 = −5.8 ± 0.3 e.u.). Additional data for the hydrogen bonded complexes 3a,b and 7a,b were determined via NMR titrations in d8-toluene from the equilibrium constants Kδ) and KR1) measuring either changes in the chemical shifts of HW(Δδ) or the excess relaxation rates of HWR1) (3a,b: ΔHδ) = −0.8 ± 0.1 kcal/mol; ΔSδ) = −1.4 ± 0.3 e.u. and ΔHR1) = −5.8 ± 0.4 kcal/mol; ΔSR1) = −22.9 ± 1.9 e.u) (7a,b: ΔHδ) = −2.3 ± 0.2 kcal/mol; ΔSδ) = −11.7 ± 0.9 e.u. and ΔHR1) = −2.9 ± 0.2 kcal/mol; ΔSR1) = −14.6 ± 1.0 e.u). Dihydrogen bonding distances of 1.9 Å and 2.1 Å were derived for 3a and 7a from the NMR excess relaxation rate measurements of HW in d8-toluene. An X-ray diffraction study was carried out on compound 2.  相似文献   

17.
The new heteroleptic mercury(II) complex PhHgN(SiMe3)2(1) reacts with the strong Brønsted acid [H(OEt2)2][H2N{B(C6F5)3}2] with cleavage of a N-Si bond to give [C6H5Hg(H2NSiMe3)][H2N{B(C6F5)3}2] (2), a phenyl-mercury(II) cation stabilised by a primary amine and a non-coordinating counter-anion. Attempts to generate donor-free aryl mercury cations were not successful. The crystal structure of 2 · CH2Cl2 shows short π-bonding interactions between the metal and the phenyl ring of a neighbouring cation; the geometry about the mercury(II) atom is nearly linear. The X-ray structures of the new salts [H2N(SiMe3)2 · H3NSiMe3][B(C6F5)4]2 and [Et3O][H2N{B(C6F5)3}2] · CH2Cl2 are also presented.  相似文献   

18.
Reactions of [Pt2(μ-Cl)2(C8H12OMe)2] (1) (C8H12OMe = 8-methoxy-cyclooct-4-ene-1-yl) with various anionic chalcogenolate ligands have been investigated. The reaction of 1 with Pb(Spy)2 (HSpy = pyridine-2-thiol) yielded a binuclear complex [Pt2(Spy)2(C8H12OMe)2] (2). A trinuclear complex [Pt3(Spy)4(C8H12OMe)2] (3) was isolated by a reaction between 2 and [Pt(Spy)2]n. The reaction of 1 with HSpy in the presence of NaOMe generated 2 and its demethylated oxo-bridged tetranuclear complex [Pt4(Spy)4(C8H12-O-C8H12)2] (4). Treatment of 1 with ammonium diisopropyldithiophosphate completely replaced C8H12OMe resulting in [Pt(S2P{OPri}2)2] (5), whereas non-rigid 5-membered chelating ligand, Me2NCH2CH2E, produced mononuclear complexes [Pt(ECH2CH2NMe2)(C8H12OMe)] (E = S (6), Se (7)). These complexes have been characterized by elemental analyses, NMR (1H, 13C{1H}, 195Pt{1H}) and absorption spectroscopy. Molecular structures of 2, 3, 4, 5 and 7 were established by single crystal X-ray diffraction analyses. Thermolysis of 2, 6 and 7 in HDA gave platinum nanoparticles.  相似文献   

19.
Reactions of Me5Al3[OC(C6H5)2C(C6H5)2O]2 (1) with alcohols ROH (R = Me, Et, tBu) in a 1:1 molar ratio afforded the compound Me2Al2[OC(C6H5)2C(C6H5)2O]2(C4H8O) (2) and a mixture of methylaluminum alkoxides. The alcohols acted as the factor formally eliminating a molecule of Me3Al (as a methylaluminum alkoxide) from compound 1. tBu3Al reacted with an equimolar amount of benzopinacol to form the monomeric complex tBuAl[OC(C6H5)2C(C6H5)2O](C4H8O) (3). Reactions of Me3Ga and Me3In with benzopinacol yielded trinuclear complexes Me5M3[OC(C6H5)2C(C6H5)2O]2 (4 (M = Ga), 5 (M = In)), isostructural to compound 1. In the presence of water and alcohols, compounds 4 and 5 underwent a decomposition reaction to benzopinacol and a mixture of metalloxanes and alkoxides. An unusual methylmethoxo indium benzopinacolate Me6In4[OC(C6H5)2C(C6H5)2O]2(OCH3)2 (6) was obtained in the reaction of benzopinacol with Me3In and Me2InOMe in a 1:1:1 molar ratio. Molecular structures of the compounds 3, 4 and 6 were determined by X-ray crystallography.  相似文献   

20.
Diorganodiselenide [2-(Et2NCH2)C6H4]2Se2 (1) was obtained by hydrolysis/oxidation of the corresponding [2-(Et2NCH2)C6H4]SeLi derivative. The treatment of [2-(Et2NCH2)C6H4]2Se2 with elemental sodium in THF resulted in [2-(Et2NCH2)C6H4]SeNa (2). Reactions between alkali metal selenolates [2-(R2NCH2)C6H4]SeM′ (R = Me, Et; M′ = Li, Na) and MCl2 (M = Zn, Cd) in a 2:1 molar ratio resulted in the [2-(R2NCH2)C6H4Se]2M species [R = Me, M = Zn (3), Cd (4); R = Et, M = Zn (5), Cd (6)]. The new compounds were characterized by multinuclear NMR (1H, 13C, 77Se, 113Cd) and mass spectrometry. The crystal and molecular structures of 1, 3 and 4 revealed monomeric species stabilized by N → Se (for 1) and N → M (for 3 and 4) intramolecular interactions.  相似文献   

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