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1.
Syntheses of (4E,6E,11Z)-4,6,11-hexadecatrienyl acetate (1) and (4E,6E, 11Z)-4, 6,11-hexadecatrienal (2), female sex pheromones of eri-silkworm,Samia cynthia ricini have been achieved through Claisen ortho ester rearrangement of (6).  相似文献   

2.
On Polychalcogenides of Thallium with M2Q11 Groups as a Structural Building Block. I Preparation, Properties, X‐ray Diffractometry, and Spectroscopic Investigations of Tl4Nb2S11 and Tl4Ta2S11 The new ternary compounds Tl4Nb2S11 and Tl4Ta2S11 were prepared using Thallium polysulfide melts. Tl4M2S11 crystallises isotypically to K4Nb2S8.9Se2.1 in the triclinic space group P 1 with a = 7.806(2) Å, b = 8.866(2) Å, c = 13.121(3) Å, α = 72.72(2)°, β = 88.80(3)°, and γ = 85.86(2)° for M = Nb and a = 7.837(1) Å, b = 8.902(1) Å, c = 13.176(1) Å, α = 72.69(1)°, β = 88.74(1)°, and γ = 85.67(1)° for M = Ta. The interatomic distances as well as angles within the [M2S11]4– anions are similar to those of the previously reported data for analogous alkali metal polysulfides. Significant differences between Tl4M2S11 and A4M2S11 (A = K, Rb, Cs) are obvious for the shape of the polyhedra around the electropositive elements. The two title compounds melt congruently at 732 K (M = Nb) and 729 K (M = Ta). The optical band gaps were estimated as 1.26 eV for Tl4Nb2S11 and as 1.80 eV for the Tantalum compound.  相似文献   

3.
Pure (7E,9Z-7, 9-dodecadien-1-yl acetate (1), the sex pheromone of Lobesiabotrana, has been prepared in 21.6% overall yield by a reaction scheme involving; (i) the cross-coupling of (E) - 8 - (2 - tetrahydropyranyloxy) -1 - octenyldisiamylborane with 1 - bromo - 1 - butyne, in the presence of a Pd (O) catalyst and base; (ii) the acetylation of the crude product of this reaction; (iii) the (Z)-stereoselective reduction of the obtained conjugated (E)-enyn-1-yl acetate. (E)-9,11-Dodecadien-1-yl acetate (2), a sex pheromone component of Diparopsiscastanea, has been analogously obtained (in 54.3% overall yield) by cross-coupling of (E) - 10 - (2 - tetrahydropyranyloxy) - 1 - decenyl borane with vinyl bromide, in the presence of a Pd (O) catalyst and base, followed by acetylation of the crude product. Compound 2, which was 87.7% chemically pure, was purified by column chromatography over SiO2-AgNO3. Chemically pure (9Z, 11E) - 9,11 - tetradecadien - 1 - yl acetate (3), a sex pheromone component of Spodopteralittoralis, has been prepared (in 30.2% overall yield) by reaction of 10 - (2 - tetrahydropyranyloxy) - 1 - decynylamagnesium bromide with (E)-1-iodo-1-butene, in the presence of a Pd (O) catalyst, followed by acetylation of the crude product and by (Z)-stereoselective reduction of the obtained (E)-enyn-1-yl acetate.The stereoisomeric purity of 1, 2 and 3 has been evaluated by glc analysis on glass capillary columns or by reverse phase hplc analysis.  相似文献   

4.
trans-11,12-Epoxy-(6Z,9Z)-6,9-henicosadiene (posticlure) has been identified from a pheromone gland of the lymantriid species, Orgyia postica. Since the diversity of Lepidoptera suggests that some species utilize the structure-related epoxy compound as a sex pheromone component, epoxydienes and epoxytrienes derived from (6Z,9Z,11E)-6,9,11-trienes and (3Z,6Z,9Z,11E)-3,6,9,11-tetraenes with a C19–C21 chain were systematically synthesized and the chemical data were accumulated in order to contribute to a new pheromone research. Peracid oxidation of each triene and each tetraene produced, respectively, a mixture of three epoxydienes (cis-6,7-epoxy-9,11-diene; cis-9,10-epoxy-6,11-diene; and trans-11,12-epoxy-6,9-diene) and four epoxytrienes (cis-3,4-epoxy-6,9,11-triene; cis-6,7-epoxy-3,9,11-triene; cis-9,10-epoxy-3,6,11-triene; and trans-11,12-epoxy-3,6,9-triene). While the 9,10-epoxy compounds were unstable and, interestingly, converted into 9-ketone derivatives after chromatography over SiO2, each positional isomer was isolated by HPLC equipped with an ODS column, and the chemical structure was determined by NMR analysis. On the GC-MS analysis with a DB-23 column, the positional isomers were also eluted separately and characteristic mass spectra were proposed. By comparing the spectral data of the epoxy compounds with a different carbon chain, diagnostic fragment ions reflecting the chemical structure were determined as follows: m/z 79, 109, 113, and M-114 for the 6,7-epoxydienes; m/z 69, 97, 111, 139, and M-111 for the 9,10-epoxydienes; m/z 57, 79, 109, 136, M-151, and M-111 for the 11,12-epoxydienes; m/z 79, 91, 105, and 119 for the 3,4-epoxytrienes; m/z 79, 124, M-124, M-96, and M-69 for the 6,7-epoxytrienes; m/z 79, 95, 109, 137, and M-108 for the 9,10-epoxytrienes; and m/z 79, 134, M-149, M-109, and M-95 for the 11,12-epoxytrienes.  相似文献   

5.
The new ultraphosphates FeP4O11, ZnP4O11 and CdP4O11 of the CuP4O11 structure type were synthesized from the corresponding meta- or polyphosphates and P4O11. Crystallization via the gas phase has been achieved at elevated temperatures using a mixture of P (3 mg) and I2 (50 mg) as mineralizer. The crystal structure consists of a two-dimensional phosphate network, built from four crystallographically independent 10-membered polyphosphate rings. Each ring contains four secondary and six tertiary PO4-groups. Two crystallographically independent metal sites showing sixfold coordination by terminal oxygen atoms are located inbetween the phosphate layers. FeO6-octahedra (2.028(3) Å < d̄ FeO6 < 2.268(3) Å) and ZnO6 octahedra (2.002(2) Å < d̄ ZnO6 < 2.256(2) Å) exhibit slightly larger radial distortion than the CdO6-octahedra (2.215(7) Å < d̄ CdO6 < 2.383(3) Å).  相似文献   

6.
Heterometallic Complexes with E6 Ligands (E = P, As) The reaction of [Cp*Co(μ-CO)]2 1 with the sandwich complexes [Cp*Fe(η5-E5)] 2 a: E = P, 2 b: E = As in decalin at 190°C affords besides [CpCo2E4] 4: E = P, 7: E = As and [CpFe2P4] 5 the trinuclear complexes [(Cp*Fe)2(Cp*Co)(μ-η2-P2)(μ31:2:1-P2)2] 3 as well as [(Cp*Fe)2(Cp*Co)(μ32:2:2-As3)2] 6 . With [Mo(CO)5(thf)] 3 and 6 form in a build-up reaction the tetranuclear clusters [(Cp*Fe)2(Cp*Co)E6{Mo(CO)3}] 10: E = P, 11: E = As. 3, 6 and 11 have been further characterized by an X-ray crystal structure determination.  相似文献   

7.
The System Gd/Co/B: Preparation and Characterization by X‐ray Diffraction of GdCo4B, Gd3Co11B4, GdCoB4, and GdCo12B6 The compounds GdCo4B, Gd3Co11B4, GdCoB4, and GdCo12B6 were characterized by X‐ray investigations of single crystals. GdCo4B (P 6/mmm, a = 505.9(1) pm, c = 690.1(1) pm) crystallizes with the CeCo4B structure type; Gd3Co11B4 (P 6/mmm, a = 508.7(1) pm, c = 982.9(9) pm) with the Ce3Co11B4 stucture type; GdCo12B6 ( , a = 949.5(1) pm, c = 747.4(1) pm) with the SrNi12B6 structure type and GdCoB4 (P bam, a = 591.3(9) pm, b = 1145.1(6) pm, c = 346.2(3) pm) with the YbCoB4 structure type.  相似文献   

8.
The behavior of different anilines H2NC6H4R (R = o-Me, p-Me, o-, m- and p? i Pr, p-OMe, p-CO2Et) and 2,6-Me2C6H3NH2 towards trihalophosphoranes was studied. 2,6-Me2C6H3NH2 failed to form the diaminophosphonium salt [Ph2PNH(2,6-Me2C6H3)2]Br, and the aminophosphine oxide Ph2(2,6-Me2C6H3NH)PO was the only isolated product. Both o- and p-toluidine gave the corresponding diaminophosphonium salts; however in the case of o-toluidine, the yield was low and a mixture with the respective aminophosphine oxide was observed. Anilines containing methoxy and ethoxycarbonyl groups in para-position form the diaminophosphonium salts in reasonable yields.  相似文献   

9.
The use of [Cp′′2Zr(η1:1-E4)] (E=P ( 1 a ), As ( 1 b ), Cp′′=1,3-di-tert-butyl-cyclopentadienyl) as phosphorus or arsenic source, respectively, gives access to novel stable polypnictogen transition metal complexes at ambient temperatures. The reaction of 1 a/1 b with [CpRNiBr]2 (CpR=CpBn (1,2,3,4,5-pentabenzyl-cyclopentadienyl), Cp′′′ (1,2,4-tri-tert-butyl-cyclopentadienyl)) was studied, to yield novel complexes depending on steric effects and stoichiometric ratios. Besides the transfer of the complete En unit, a degradation as well as aggregation can be observed. Thus, the prismane derivatives [(Cp′′′Ni)2(μ,η3:3-E4)] ( 2 a (E=P); 2 b (E=As)) or the arsenic containing cubane [(Cp′′′Ni)33-As)(As4)] ( 5 ) are formed. Furthermore, the bromine bridged cubanes of the type [(CpRNi)3{Ni(μ-Br)}(μ3-E)4]2 (CpR=Cp′′′: 6 a (E=P), 6 b (E=As), CpR=CpBn: 8 a (E=P), 8 b (E=As)) can be isolated. Here, a stepwise transfer of En units is possible, with a cyclo-E42− ligand being introduced and unprecedented triple-decker compounds of the type [{(CpRNi)3Ni(μ3-E)4}2(μ,η4:4-E′4)] (CpR=CpBn, Cp′′′; E/E′=P, As) are obtained.  相似文献   

10.
Systems Tl2MoO4-E(MoO4)2 (E = Zr, Hf) are studied using X-ray powder diffraction, DTA, and IR spectroscopy. Compounds Tl8E(MoO4)6 and Tl2E(MoO4)2 are found in these systems. T-x diagrams for the Tl2MoO4-Zr(MoO4)2 system are designed. Single crystals are grown and structure is solved for Tl8Hf(MoO4)6. The compound crystallizes in a monoclinic structure with the unit cell parameters a = 9.9688(6) Å, b = 18.830(1) Å, c = 7.8488(5) Å, β = 108.538(1)°, Z = 2, space group C2/m. The main structural fragment is a [HfMo6O24]8? isle group. Three crystallographically independent types of Tl polyhedra uniformly fill spaces between [HfMo6O24]8? fragments to form a three-dimensional framework.  相似文献   

11.
Magnetic Properties of the Cobaltates Na6CoS4, Na6CoSe4, and K6CoS4 The alkali metal cobalt chalcogenides Na6CoS4, Na6CoSe4, and K6CoS4 crystallize in the space group P63mc with Z = 4. The structure is characterized by isolated [CoX4]-tetrahedra. The magnetic susceptibilities show Curie-Weiss behaviour. The deviations at low temperatures are caused by antiferromagnetic interactions. The magnetic moments are discussed with regard to ligand-field parameters.  相似文献   

12.
A synthesis was reported for 13,13,14,14,15,15,16,16-octafluoro-11-hexadecen-1-yl acetate, which is an analog of the sex pheromone of the cabbage worm(Mamestra Brassicae).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2165–2167, September, 1990.  相似文献   

13.
The structure and conducting properties of a new radical cation salt of dibenzotetrathiafulvalene (DBTTF),viz., (DBTTF)11(TeCl6)4 (1), were studied. According to the X-ray diffraction data, the crystal of1 contains six crystallographically independent DBTTF radical cations alternating with stacks of the (TeCl6)2− anions. At room temperature, the conductivity of the crystals is 15 S cm−1 and it changes exponentially as the temperature decreases. It was found that an increase in the size of the anion in compounds of type1 results in the appearance of interactions between the stacks and in an enhancement of the two-dimensional character of the conductivity. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 370–372, February, 2000.  相似文献   

14.
Zusammenfassung Bei der Umsetzung von Kaliumtellurat mit BaCl2 fällt primär BaH4TeO6, welches bei 250°C 1 1/2 Mole Wasser abgibt und erst bei über 375°C in das wasserfreie BaTeO4 übergeht. Vergleiche der Pulverdiagramme dieser Bariumtellurate untereinander und mit denen von BaSeO4 und BaSO4 werden angestellt.
BaH4TeO6 is precipitated when barium chloride is added to a solution of potassium tellurate. This compound looses 1 1/2 moles water when heated to 250°C, and forms BaTeO4 above 375°C. TheDebye-Scherrer powder diagrams of these barium tellurates are compared with each other, and with those of BaSeO4 and BaSO4.


Mit 3 Abbildungen

Frau Professor Dr.Erika Cremer anläßlich ihres Geburtstages 1965 in Verehrung gewidmet.  相似文献   

15.
The coordination properties of new types of bidentate phosphane and arsane ligands with a narrow bite angle are reported. The reactions of [{Cp′′′Fe(CO)2}2(μ,η1:1‐P4)] ( 1 a ) with the copper salt [Cu(CH3CN)4][BF4] leads, depending on the stoichiometry, to the formation of the spiro compound [{{Cp′′′Fe(CO)2}231:1:1:1‐P4)}2Cu]+[BF4]? ( 2 ) or the monoadduct [{Cp′′′Fe(CO)2}231:1:2‐P4){Cu(MeCN)}]+[BF4]? ( 3 ). Similarly, the arsane ligand [{Cp′′′Fe(CO)2}2(μ,η1:1‐As4)] ( 1 b ) reacts with [Cu(CH3CN)4][BF4] to give [{{Cp′′′Fe(CO)2}231:1:1:1‐As4)}2Cu]+[BF4]? ( 5 ). Protonation of 1 a occurs at the “wing tip” phosphorus atoms, which is in line with the results of DFT calculations. The compounds are characterized by spectroscopic methods (heteronuclear NMR spectroscopy and IR spectrometry) and by single‐crystal X‐ray diffraction studies.  相似文献   

16.
The oxidation of (E,E,Z)-1,5,9-cyclododecatriene catalysed by Pd(OAc)2/Cu(OAc)2 was studied in methyl alcohol solutions at 2.5 MPa air pressure and temperature range of 358 to 383 K. The selectivity of ketones and ethers at conversion of cyclododecatriene up to 32.7% ranged within 87.5–96.0%. The reaction network and kinetic equations proposed suggested a significant inhibition effect of the ketones and ethers and gave the best agreement with the experimental data.  相似文献   

17.
Tachibana  M.  Tojo  T.  Kawaji  H.  Atake  T.  Morita  N.  Ikuta  H.  Uchimoto  Y.  Wakihara  M. 《Journal of Thermal Analysis and Calorimetry》2002,69(3):997-1004
Heat capacity of spinel LiCr1/6Mn11/6O4-d (d=0, 0.0184)was measured between 5 and 300 K. Both compounds showed no anomaly in the measured temperature range, especially around the room temperature where a structural phase transition is reported for the parent compound LiMn2O4. The non-stoichiometric compound LiCr1/6Mn11/6O3.9816 has greater heat capacity than that of the stoichiometric LiCr1/6Mn11/6O4. Molecular dynamics study on the vibrational property of LiMn2O4-d revealed that the lattice defects in the non-stoichiometric compound increase the low frequency phonons compared with the stoichiometric compound. It should be related to the greater heat capacity of the non-stoichiometric compound LiCr1/6Mn11/6O3.9816. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

18.
Polycationic Hg–As Frameworks with Trapped Anions. II Synthesis, Crystal Structure, and Magnetism of (Hg6As4)[MoCl6]Cl, (Hg6As4)[TiCl6]Cl, and (Hg6As4)[TiBr6]Br (Hg6As4)[MoCl6]Cl is obtained by reaction of Hg2Cl2, Hg, As, and MoCl4 in closed, evacuated glass ampoules in a temperature gradient 450 → 400 °C in form of dark red cubelike crystals. (Hg6As4)[TiCl6]Cl and (Hg6As4)[TiBr6]Br are also formed in closed, evacuated ampoules from Hg2X2 (X = Cl, Br), Hg, As, and Ti metal at 275 °C and 245 °C in form of dark green and black crystals, respectively. All three compounds are air and light sensitive. They crystallize isotypically (cubic, Pa 3, a = 1207.8(4) pm for (Hg6As4)[MoCl6]Cl, a = 1209.4(3) pm for (Hg6As4)[TiCl6]Cl, a = 1230.9(3) pm for (Hg6As4)[TiBr6]Br, Z = 4). The structures consist of a three‐dimensionally connected Hg–As framework which is made up of As2 groups (As–As distance averaged 242 pm) each connected via six Hg atoms to six neighbouring As2 groups. There are two cavities of different size in the polycationic framework. The bigger cavity is filled with [MoCl6]3–, [TiCl6]3–, and [TiBr6]3– ions of nearly ideal octahedral shape, the smaller cavity with discrete halide ions. The magnetic properties of the two Ti containing compounds are in accordance with a d1 paramagnetism. The temperature dependence and the magnitude of the magnetic moment can be interpreted with consideration of the spin‐orbit coupling. The so far known representatives of this structure type can be characterised by the ionic formula (Hg6Y4)4+[MX6]3–X (Y = As, Sb; M = Sb3+, Bi3+, Mo3+, Ti3+; X = Cl, Br).  相似文献   

19.
Both Syxyn11P and Syxyn11E, two codon-optimized genes encoding glycoside hydrolase (GH) family 11 hyperthermotolerant xylanases (designated SyXyn11P and SyXyn11E), were synthesized and inserted into pPIC9KM and pET-28a(+) vectors, respectively. The resulting recombinant expression vectors, pPIC9KM-Syxyn11P and pET-28a(+)-Syxyn11E, were transformed into Pichia pastoris GS115 and Escherichia coli BL21, respectively. The maximum activities of two recombinant xylanases (reSyXyn11P and reSyXyn11E) expressed in P. pastoris and E. coli reached 30.9 and 17.8 U/ml, respectively. The purified reSyXyn11P and reSyXyn11E displayed the same pH optimum at 6.5 and pH stability at a broad range of 4.5–9.0. The temperature optimum and stability of reSyXyn11P were 85 and 80 °C, higher than those of reSyXyn11E, respectively. Their activities were not significantly affected by metal ions tested and EDTA, but strongly inhibited by Mn2+ and Ag+. The K m and V max of reSyXyn11P toward birchwood xylan were 4.3 mg/ml and 694.6 U/mg, whose K m was close to that (4.8 mg/ml), but whose V max was much higher than that (205.6 U/mg) of reSyXyn11E. High-performance liquid chromatography analysis indicated that xylobiose and xylotriose as the major products were excised from insoluble corncob xylan by reSyXyn11P.  相似文献   

20.
By the reaction of [NacnacCuCH3CN] with white phosphorus (P4) and yellow arsenic (As4), the stabilization and enclosure of the intact E4 tetrahedra are realized and the disubstituted complexes [(NacnacCu)2(μ,η2:2‐E4)] ( 1 a : E=P, 1 b : E=As) are formed. The mono‐substituted complex [NacnacCu(η2‐P4)] ( 2 ), was detected by the exchange reaction of 1 a with P4 and was only isolated using low‐temperature work‐up. All products were comprehensively spectroscopically and crystallographically characterized. The bonding situation in the products as intact E4 units (E=P, As) was confirmed by theory and was experimentally proven by the pyridine promoted release of the bridging E4 tetrahedra in 1 .  相似文献   

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