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1.
139La-NMR chemical shifts were measured for several anionic complexes of formulae Li(C 4H 8O 2) 3/2 [La(ν 3-C 3H 5) 4], [Li(C 4H 8O 2) 2][Cp′ nLa(ν 3-C 3]H 5) 4−n] (Cp′ = Cp(ν 5-C 5H 5); n = 1, 2 and Cp′ = Cp * (ν 5-C 5Me5); N = 1) and Li[R nLa(ν 3-C 3H 4) 4− n] (R = N(SiMe 3) 2; n = 1, 2 and R = CCsIMe 3; n = 4), as well as for neutral compounds for formulae La(ν 3-C 3H 5) 3L n (L = (C 4H 8O 2) 1.5, (HMPT) 2, TMED), Cp′ nLa(ν 3-C 3H 5) 3−n (Cp′= Cp(ν 5-Cp 5H 5), Cp *(ν 5-C 5Me 5); n = 1, 2) and La(ν 3-C 3H 2) 2X(THF) 2 X = Cl, Br, I). Typical ranges of the 139La-NMR chemical shifts were found for the different types of complex independent of number and kind of organyl groups directly bonded to lanthanum. Zusammenfassung139La-NMR-Spektroskopie wurde an einer Reihe anionischer Allyllanthanat(III)-Komplexe der Zusammensetzung
]- [La)ν3-C3H5)4, [Li(C4H8)2][Cp′nLa(ν3-C3H5)4−n(Cp′ = Cp(ν5-C5H5); n = 1, 2 und Cp′ = Cp * (ν5-C5Me5); N = 1) und Li[RnLa(ν3-C3H5)4−n (R = B(SiMe3)2; n = 1, 2 und R = CCSiMe3; n = 4 sowie neutraler Allyllanthan(III)-Komplexe der Zusammensetzung La(ν3-C3H5)3Ln (Ln = (C4H8O2)1.5, (HMPT)2, TMED), Cp′n, La(ν3-C3H5)3−n (Cp′ = Cp(ν5-C5H5), Cp * (ν5- Cp5Me5); n = 1, 2) und La(ν3-Cp3H5)2X(THF)2 (X = Cl, Br, I) durchgefürt. In Abhängikeit von der Anzahl und der Art der am Lanthan gebundenen Gruppen wurden für die verschieden Komplextypen charakteristische Resonanzbereiche ermittelt. 相似文献
2.
Halogenated trisilanes X nSi 3H 8−n with X = Cl, Br, I and n = 2–7 as well as the tetrasilanes H 2XSiSiX 2SiX 2SiX 2H have been prepared by dearylation of appropriate aryltrisilanes and aryltetrasilanes (aryl = phenyl, p-tolyl) with either liquid or gaseous hydrogen halides. The compounds have been characterized with elemental analysis as well as 29Si NMR spectroscopy. 相似文献
3.
The synthesis and reactivity of {(η 5-C 5H 4SiMe 3) 2Ti(CCSiMe 3) 2} MCl 2 (M = Fe: 3a; M = Co: 3b; M = Ni: 3c) is described. The complexes 3 are accessible by the reaction of (η 5-C 5H 4SiMe 3) 2Ti(CSiMe 3) 2 (1) with equimolar amounts of MCl 2 (2) (M = Fe, Co, Ni). 3a reacts with the organic chelat ligands 2,2′-dipyridyl (dipy) (4a) or 1,10-phenanthroline (phen) (4b) in THF at 25°C to afford in quantitative yields (η 5-C 5H 4SiMe 3) 2Ti(CSiMe 3) 2 (1) and [Fe(dipy) 2]Cl 2 (5a) or [Fe(phen) 2]Cl 2 (5b). 1/ n[Cu IHal] n (6) or 1/ n[Ag IHal] n (7) (Hal = Cl, Br) react with {(η 5 -C 5H 4SiMe 3) 2Ti(CCSiMe 3) 2}FeCl 2 (3a), by replacement of the FeCl 2 building block in 3a, to yield the compounds {(η 5-C 5H 4SiMe 3) 2Ti(C CSiMe 3) 2}Cu IHal (8) or {(η 5-C 5H 4SiMe 3) 2Ti(CSiMe 3) 2}Ag IHal (9) (Hal = Cl, Br), respectively. In 8 and 9 each of the two Me 3SiCC-units is η 2-coordinated to monomeric Cu I Hal or Ag IHal moieties. Compounds 8 and 9 can also be synthesized by the reaction of (η 5-C 5H 4SiMe 3) 2 Ti(CSiMe 3) 2 (1) with 1/ n[Cu IHal] n (6) or 1/ n [Ag IHal] n (7) in excellent yields. All new compounds have been characterized by analytical and spectroscopic data (IR, 1H-NMR, MS). The magnetic moments of compounds 3 were measured. 相似文献
4.
The syntheses and properties of the iodotrisilanes (IH 2Si) 2SiH 2, (IH 2Si) 2SiHI, I 3SiSiI 2SiH 3, (I 3Si) 2SiH 2 and Si 3I 8 are reported. All trisilanes were synthesized from the appropriate phenyltrisilanes and hydrogen iodide, with the exception of I 5Si 3H 3, which was prepared by thermolysis of I 3SiSiH 3. The 29 Si-chemical shifts and 29Si 29Si-coupling constants are reported. ab]Die Synthesen und Eigenschaften der Iodtrisilane (IH 2Si) 2SiH 2, (IH 2Si) 2SiHI, I 3SiSiI 2SiH 3, (I 3Si) 2SiH 2 und Si 3I 8 werden beschrieben. Bis auf I 5Si 3H 3, das während der Thermolyse von I 3SiSiH 3, entstand, wurden alle Iodtrisilane aus den entsprechenden Phenyltrisilanen mit Iodwasserstoff hergestellt. Die 29Si-Verschiebungen und 29Si 29Si-Kopplungskonstanten werden mitgeteilt. 相似文献
5.
Ferrocenyl-1,2-diketones FcCOCOR, 3, [Fc = (C 5H 5)Fe(C 5H 4)] can be prepared by oxidation of acylferrocenes FcCOCH 2R or, more efficiently, by oxidation of the isomeric ketones FcCH 2COR, 2. The ketones 2 are in turn readily synthesized from the salt (FcCH 2PPh 3) +I − via the acylated salts [FcCH(COR)PPh 3] +I −. The haloacylferocenes FcCOCCl x H 3−x ( x = 1, 2, 3, of which the x = 2 example is synthetically equivalent to a diketone) are synthesized by Friedel—Crafts acylation of ferrocene using CCl xH 3−xCOCl/AlCl 3, but the reaction proceeds via two parallel pathways, one giving the normal acyl derivatives FcCOCCl xH 3−x and the other giving the reduced products FcCOCCl x−1H 4−x. Two diketones FcCOCOFc 3b and FcCOCOC 6H 4Ph 3c have been structurally characterised by single-crystal X-ray diffraction. 相似文献
6.
Lamellar crystalline calcium phenylphosphonate, as anhydrous Ca(HO 3PC 6H 5) 2 and hydrated Ca(HO 3PC 6H 5) 2·2H 2O compounds, were used as hosts for intercalation of polar n-alkylmonoamine molecules of the general formula CH 3(CH 2) nNH 2 ( n=0–4, 7) in water or 1,2-dichloroethane. An increase in the interlayer distance was observed. The exothermic enthalpic values for intercalation increased with the number of carbon atoms and with increasing concentration of the amines. The intercalation followed by a titration procedure in the solid/liquid interface with Ca(HO 3PC 6H 5) 2·2H 2O and Ca(HO 3PC 6H 5) 2 gave the enthalpy/number of carbons correlations: Δ intH=−(1.74±0.43)–(1.30±0.13) nc and Δ intH=−(4.15±0.15)–(1.07±0.03) nc, for water and 1,2-dichloroethane, respectively. A similar correlation Δ intH=−(4.27±0.80)–(1.85±0.21) nc was obtained in water by using the ampoule breaking procedure for Ca(HO 3PC 6H 5) 2·2H 2O. The increase in exothermic enthalpic values with the increase in n-aliphatic carbon atoms is more pronounced for the anhydrous compound and also when using the ampoule breaking procedure. The Gibbs free energies are negative. Positive entropic values favor intercalation in these systems. 相似文献
7.
The new chloro(cyclopentadienyl)silanes Cp′SiH yCl 3−y (Cp′=Me 4EtC 5, y=1: 1; Cp′=Me 4C 5H, y=1: 2; y=0: 3; Cp′=Me 3C 5H 2, y=1: 4 and pentachloro(cyclopentadienyl)disilanes Cp′Si 2Cl 5 (Cp′=Me 5C 5 5, Me 4EtC 5 6, Me 4C 5H 7, Me 3C 5H 2 8, Me 3SiC 5H 4 9) are synthesized in good yields via metathesis reactions. Treatment of 1–9 with LiAlH 4 leads under Cl–H exchange to the hydridosilyl compounds Cp′SiH 3 (Cp′=Me 4EtC 5 10, Me 4C 5H 11, Me 3C 5H 2 12) and to the hydridodisilanyl compounds Cp′Si 2H 5 (Cp′=Me 5C 5 13, Me 4EtC 5 14, Me 4C 5H 15, Me 3C 5H 2 16, Me 3SiC 5H 4 17). Complexes 1–17 are characterized by 1H, 13C, and 29Si-NMR spectroscopy, IR spectroscopy, mass spectrometry and CH-analysis. The structures of 6, 7 and 9 are determined by single-crystal X-ray diffraction analysis. Pyrolysis studies of the cyclopentadienylsilanes 10–12 and disilanes 13–17 show their suitability as precursors in the MOCVD process. 相似文献
8.
A series of novel arylantimony(V) triphenylgermanylpropionates with the formula (Ph 3GeCHR 1CHR 2CO 2) nSbAr (5−n) (R 1=H, Ph; R 2=H, CH 3; n=1, 2) were synthesized and characterized by elemental analysis, IR, 1H-NMR, 13C-NMR and mass spectroscopy. The crystal structures of Ph 3GeCH(Ph)CH 2CO 2SbPh 4 and [Ph 3GeCH 2CH(CH 3)CO 2] 2Sb(4-ClC 6H 4) 3 were determined by X-ray diffraction. The in vitro antitumor activities of some selected compounds against five cancer cells are reported. 相似文献
9.
High resolution vibration-rotation spectra of 13C 2H 2 were recorded in a number of regions from 2000 to 5200 cm −1 at Doppler or pressure limited resolution. In these spectral ranges cold and hot bands involving the bending-stretching combination levels have been analyzed up to high J values. Anharmonic quartic resonances for the combination levels ν 1 + mν 4 + nν 5, ν 2 + mν 4 + ( n + 2) ν 5 and ν 3 + ( m − 1) ν 4 + ( n + 1) ν 5 have been studied, and the l-type resonances within each polyad have been explicitly taken into account in the analysis of the data. The least-squares refinement provides deperturbed values for band origins and rotational constants, obtained by fitting rotation lines only up to J ≈ 20 with root mean square errors of ≈ 0.0003 cm −1. The band origins allowed us to determine a number of the anharmonicity constants xij0. 相似文献
10.
The reactions of RNHSi(Me) 2Cl (1, R= t-Bu; 2, R=2,6-(Me 2CH) 2C 6H 3) with the carborane ligands, nido-1-Na(C 4H 8O)-2,3-(SiMe 3) 2-2,3-C 2B 4H 5 (3) and Li[ closo-1-R′-1,2-C 2B 10H 10] (4), produced two kinds of neutral ligand precursors, nido-5-[Si(Me) 2N(H)R]-2,3-(SiMe 3) 2-2,3-C 2B 4H 5, (5, R= t-Bu) and closo-1-R′-2-[Si(Me) 2N(H)R]-1,2-C 2B 10H 10 (6, R= t-Bu, R′=Ph; 7, R=2,6-(Me 2CH) 2C 6H 3, R′=H), in 85, 92, and 95% yields, respectively. Treatment of closo-2-[Si(Me) 2NH(2,6-(Me 2CH) 2C 6H 3)]-1,2-C 2B 10H 11 (7) with three equivalents of freshly cut sodium metal in the presence of naphthalene produced the corresponding cage-opened sodium salt of the “carbons apart” carborane trianion, [ nido-3-{Si(Me) 2N(2,6-(Me 2CH) 2C 6H 3)}-1,3-C 2B 10H 11] 3− (8) in almost quantitative yield. The reaction of the trianion, 8, with anhydrous MCl 4 (M=Ti and Zr) in 1:1 molar ratio in dry tetrahydrofuran (THF) at −78 °C, resulted in the formation of the corresponding half-sandwich neutral d 0-metallacarborane, closo-1-M[(Cl)(THF) n]-2-[1′-η 1σ-N(2,6-(Me 2CH) 2C 6H 3)(Me) 2Si]-2,4-η 6-C 2B 10H 11 (M=Ti (9), n=0; M=Zr (10), n=1) in 47 and 36% yields, respectively. All compounds were characterized by elemental analysis, 1H-, 11B-, and 13C-NMR spectra and IR spectra. The carborane ligand, 7, was also characterized by single crystal X-ray diffraction. Compound 7 crystallizes in the monoclinic space group P2 1/ c with a=8.2357(19) Å, b=28.686(7) Å, c=9.921(2) Å; β=93.482(4)°; V=2339.5(9) Å 3, and Z=4. The final refinements of 7 converged at R=0.0736; wR=0.1494; GOF=1.372 for observed reflections. 相似文献
11.
A performance evaluation of Density Functional Tight Binding (DFTB) in the two-layer ONIOM method is presented in an effort to estimate DFTB effectiveness as an inexpensive low level quantum mechanical layer. Ground state geometries, geometry error, S-values and energy error for: (H 2O) x(MeOH) y, [(η 5-C 5Me nH 5−n) 2Ti] 2(μ 2, η 2,η 2-N 2), n = 4, and complexes of Cu + with tyrosine, were compared to target calculations at B3LYP level of theory for all three of the systems and second order Moller-Plesset (MP2) target level of theory for the first two systems. The calculated root-mean-square errors (RMS) of the ONIOM optimized geometries relative to the target are found to be small. The DFTB level of theory was unable to reproduce the target geometry structure for one of the isomers of tyrosine–Cu + complex, while the ONIOM combinations were able to reproduce all target structures. The absolute value of the geometry error was determined to be smaller then the corresponding energy error except for the (H 2O) x(MeOH) y system at the ONIOM(MP2/6-31G(d,p):DFTB) level of theory. The S-values were relatively small and close in value contributing to relatively small energy errors. Both method combinations ONIOM(MP2:DFTB) and ONIOM(DFT:DFTB) show similar performance compared to the corresponding target level of theory. The results also suggest that it is safe to use ONIOM(DFT:DFTB) for investigations of [(η 5-C 5Me nH 5−n) 2Ti] 2(μ 2, η 2,η 2-N 2) complexes. 相似文献
12.
Excess molar enthalpies HE and excess molar volumes VE have been measured, as a function of mole fraction x1, at 298.15 K and atmospheric pressure for the five liquid mixtures ( x11,4-C 6H 4F 2 + x2n-C lH 2l+2), l = 7, 8, 10, 12 and 16. In addition, HE and excess molar heat capacities CPE at constant pressure have been determined for the two liquid mixtures ( x1C 6F 6 + x2n-C lH 2l+2), l = 7 and 14, at the same temperature and pressure. The instruments used were flow microcalorimeters of the Picker design (the HE version was equipped with separators) and a vibrating-tube densimeter, respectively. The excess enthalpies of the five difluorobenzene mixtures are all positive and quite large; they increase with increasing chain length l of the n-alkane from HE(x1 = 0.5)/(J mol−1) = 1050 for l = 7 to 1359 for l = 16. The corresponding excess volumes VE are all positive and also increase with increasing l: VE(x1 = 0.5)/(cm3 mol−1) = 0.650 for l = 7 and 1.080 for l = 16. Interestingly, the excess enthalphies of the corresponding mixtures with hexafluorobenzene are only about 5% larger, whereas the excess volumes of (x1C6F6 + x2n-ClH2l+2) are roughly twice as large as those of their counterparts in the series containing 1,4-C6H4F2. Specifically, at 298.15 K HE(x1 = 0.5)/(J mol−1) = 1119 for (x1C6F6 + x2n-C7H16) and 1324 for (x1C6F6 + x2n-C14H30), and for the same mixtures VE(x1 = 0.5)/(cm3 mol−1) = 1.882 and 2.093, respectively. The excess heat capacities for both systems are negative and of about the same magnitude as the excess heat capacities of mixtures of fluorobenzene with the same n-alkanes (Roux et al., 1984): CPE(x1 = 0.5)/(J K−1 mol−1) = −1.18 for (x1C6F6 + x2n-C7H16), and −2.25 for (x1C6F6 + x2n-C14H30). The curve CPE vs. (x1 for x1C6F6 + x2n-C14H30) shows a sort of “hump” for x1 0.5, which is presumed to indicate emerging W-shape composition dependence at lower temperatures. 相似文献
13.
The crystal structures of propionaldehyde complex ( RS, SR)-(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 3)] + PF 6− (1b + PF 6s−; monoclinic, P2 1/ c (No. 14), a = 10.166 (1) Å, b = 18.316(1) Å, c = 14.872(2) Å, β = 100.51(1)°, Z = 4) and butyraldehyde complex ( RS, SR)-[(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 2CH 3)] + PF 6− (1c +PF 6−; monoclinic, P2 1/ a (No. 14), a = 14.851(1) Å, b = 18.623(3) Å, c = 10.026(2) Å, β = 102.95(1)°, Z = 4) have been determined at 22°C and −125°C, respectively. These exhibit C
O bond lengths (1.35(1), 1.338(5) Å) that are intermediate between those of propionaldehyde (1.209(4) Å) and 1-propanol (1.41 Å). Other geometric features are analyzed. Reaction of [(η 5-C 5H 5)Re(NO)(PPh 3)(ClCH 2Cl)] + BF 4− and pivalaldehyde gives [(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHC(CH 3) 3)] +BF 4− (81%), the spectroscopic properties of which establish a π C
O binding mode. 相似文献
14.
The reaction of [Nb(η 5-C 5H 4R) 2X 2] [1: R = SiMe 3, X = Cl; 2: R = SiMe 3, X = Br; 3: R = H, X = Cl; 4: R = t, X = Cl] with nitroso derivatives ArNO [ a: Ar = Ph; b: Ar = o-CH 3-C 3H 4; c: Ar = p-(CH 3) 2NC 6H 4] yields paramagnetic complexes formulated as [Nb(η 5-C 5H 4R)(η 3-C 5H 4R)X 2(ArNO- N, O) 1a, 1b, 1c, 2a, 3a, 4a and 4c, which have been characterized by ESR and IR spectroscopy. 相似文献
15.
A new series of 1,1'-disubstituted ferrocene compounds of the type [(η 5-C 5H 4(CH 2) nOC 6H 4C 6H 4CN] 2Fe ( 3a-d, n = 5, 6, 8, 11) incorporating a variable length alkyloxy cyanobiphenyl unit has been prepared and their mesomorphic properties have been investigated. Compounds 3b, c and d exhibit a thermotropic smectic C phase and 3c also exhibits a monotropic smectic A phase over a fairly wide range near ambient temperature. 相似文献
16.
The coordinatively unsaturated uranium(IV) complex U[N(C 6H 5) 2] 4 has been prepared via the stoichiometric reaction of diphenylamine with [(Me 3Si) 2N] 2
H 2. U[N(C 6H 5) 2] 4 coordinates Lewis bases such as Et 2O, THF, pyridine or (EtO) 3PO, based on electronic absorption spectroscopy and 1H NMR studies. Exchange between U[N(C 6H 5) 2] 4 and U[N(C 6H 5) 2] 4(L), where L is THF or pyridine, is rapid on the NMR time-scale between 307 and 323 K. Measurement of equilibrium constants for L = THF provides Δ H and Δ S values of −60 kJ mol −1 and −1.8 × 10 2 J K −1 mol −1, respectively. U[N(C 6H 5) 2] 4 coordinates and binds (EtO) 3PO much more tightly ( Keq = & > 10 4 M −1) than THF or pyridine with the exchange rate between U[N(C 6H 5) 2] 4 and U[N(C 6H 5) 2] 4[OP(OEt) 3] being close to the NMR time-scale. 相似文献
17.
Reaction of optically active ketone complexes (+)-( R)-[(η 5-C 5H 5)Re(NO)-(PPh 3)(η 1-O=C(R)(CH 3)] + BF 4− (R = CH 2CH 3, CH(CH 3) 2m C(CH 3) 3, C 6H 5) with K(s-C 4H 9) 3BH gives alkoxide complexes (+)-( RS)-(η 5-C 5H 5)Re(NO)(PPh 3)-(OCH(R)CH 3) (73–90%) in 80–98% de. The alkoxide ligand is then converted to Mosher esters (93–99%) of 79–98% de. 相似文献
18.
The new diphenolato complexes [{Mo(NO){HB(dmpz) 3}Cl} 2Q] where dmpz = 3,5-dimethylpyrazolyl and Q = OC 6H 4(C 6H 4O ( n = 1 or 2), OC 6H 4CR=CRC 6H 4O (R = H or Et), and OC 6H 4CH=CHC 6H 4CH=CHC 6H 4O have been prepared and their electrochemical properties (cyclic and differential pulse voltammetry) compared with previously reported analogues where Q = OC 6H 4O, OC 6H 4EC 6H 4O (E = SO 2, CO and S), OC 6H 4 (CO)C 6H 4 C 6H 4(CO)C 6H 4O and 1,5- and 2,7-O 2C 10H 6. The electrochemical interaction between the redox centres in the new complexes is very weak, in contrast to that in the 1,4-benzenediolato and naphthalendiolato species. The EPR spectra of the reduced mixed-valence species [{Mo(NO){HB(dmpz) 3}Cl} 2Q] − where Q = 1,3- and 1,4-OC 6H 4O and OC 6H 4SC 6H 4O shows that they are valence-trapped at room temperature, whereas those of the dianions [{Mo(NO){HB(dmpz) 3}Cl} 2Q] 2− where Q = 1,4-OC 6H 4O, OC 6H 4EC 6H 4O (E = CO or S) and OC 6H 4CH=CHC 6H 4CH=CHC 6H 4O shows that the unpaired spins on each molybdenum centre are strongly correlated ( J, the spin exchange integral A Mo, the metal-hyperfine coupling constant). The electrochemical properties and the comproportionation constants for the reaction [{Mo(NO){HB(dmpz) 3} Cl} 2Q] + [{Mo(NO){HB(dmpz) 3}Cl}O] 2] 2−2[{Mo(NO) {HB(dmpz) 3}Cl} 2Q] − where Q = diphenolato bridge, are compared with related compounds containing benzenediamido and dianilido bridges. 相似文献
19.
Powder X-ray diffraction, 119Sn NMR spectra, and 1H NMR spin–lattice relaxation times, T1, were measured for (CH 3) nNH 4−nSnCl 3 ( n=1–4). From the Rietveld analysis, it is shown that all four compounds crystallize into deformed perovskite-type structures at room temperature. The temperature dependence of 1H T1 was analyzed in terms of the CH 3 reorientation and other motions of the whole cation. Except for the phase transition in CH 3NH 3SnCl 3, which is from monoclinic to rhombohedral at 331 K, 1H T1 was continuously changed at other phase transitions in this compound as well as in the n=2–4 compounds, suggesting that the transitions are not caused by the change of the motional state of the cation but by an instability of the [SnCl 3] nn− perovskite lattice. 相似文献
20.
The methylene-bridged, mixed-chalogen compounds Fe 2(CO) 6(μ-SeCH 2Te) (1) and Fe 2(CO) 6(μ-SCH 2Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe 2(CO) 6(μ-SeTe) and Fe 2(CO) 6(μ-STe), respectively. Compounds 1 and 3 have been characterised by IR, 1H, 13C, 77Se and 125Te NMR spectroscopy. The structure of 1 has been elucidated by X-ray crystallography. The crystalsare monoclinic,space group P2 1/ n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) Å 3, Z = 4, Dc = 2.599 g cm −3 and R = 0.030 ( Rw = 0.047). 相似文献
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