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1.
Several bicyclic α-chloro enones obtained through Greene annulation of cyclic olefins are shown to undergo efficient, two step, enone transposition Luche reduction and aq. formic acid treatment. Application of this methodology to the formal synthesis of exaltone® and (±)-muscone is described. 相似文献
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Fredrik LakeChristian Linde 《Tetrahedron letters》2012,53(30):3927-3929
A high yielding gram-scale synthesis of [13C4] N-benzylpiperazine for use as a convenient and versatile building block in isotope labeling studies of clinical drug candidates is reported. 相似文献
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An acid-catalyzed Dieckmann-type reaction has been developed to access functionalized bicyclo[3.2.1]alkenediones. This methodology has been successfully extended to more substituted and larger ring homologues, providing a new and efficient route to the core of numerous attractive natural products and their analogues. 相似文献
5.
Paz Vaqueiro 《Journal of solid state chemistry》2006,179(1):302-307
Two new main group metal sulphides, [C10N4H26]0.5[InS2] (1) and [C10N4H26]0.5[GaS2] (2) have been prepared solvothermally in the presence of 1,4-bis(3-aminopropyl)piperazine and their crystal structures determined by single-crystal X-ray diffraction. Both compounds are isostructural and crystallise in the monoclinic space group P21/n (Z=4), with a=6.5628(5), b=11.2008(9), c=12.6611(9) Å and β=94.410(4)° (wR=0.035) for compound (1) and a=6.1094(5), b=11.2469(9), c=12.7064(10) Å and β=94.313(4)° (wR=0.021) for compound (2). The structure of [C10N4H26]0.5[MS2] (M=In,Ga) consists of one-dimensional [MS2]− chains which run parallel to the crystallographic a axis and are separated by diprotonated amine molecules. These materials represent the first example of solvothermally prepared one-dimensional gallium and indium sulphides. 相似文献
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A one step synthesis of 4-ketohydroazuleneiron complexes 6,7 and 8 from troponeiron tricarbonyl is described. 相似文献
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A.V. Blokhin 《Thermochimica Acta》2006,445(1):75-77
Heat capacities of crystalline 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C4mim][NTf2] and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C6mim][NTf2] in the range 80 K-Tfus were measured in an adiabatic calorimeter. Anomalies in the heat-capacity curves for the both compounds occurred near 240 K. Positions of the anomalies depended on thermal history of the samples. More stable crystals had higher heat capacities in the range 220-260 K. Below 200 K heat capacities of all the crystals of the same compound were indistinguishable. 相似文献
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W.W. Schoeller 《Tetrahedron》1973,29(6):929-931
The nature of the CC-σ-bond in cycloalkanes (3–6) is evaluated using Ruedenberg's energy partitioning method within the MINDO/2 framework. 相似文献
11.
Vinyl acetate is used as an acetylene equivalent in rhodium(III)-catalysed C-H activation/annulation with aryl ketoxime esters. Extension to an aldoxime ester allows for a concise formal synthesis of decumbenine B. 相似文献
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D. P. Domonov S. I. Pechenyuk N. L. Mikhailova A. T. Belyaevskii 《Russian Journal of Inorganic Chemistry》2007,52(7):1027-1032
The thermolysis of the complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 (I) and [Co(NH3)6]Cl[Cu(C7H4O3)2] (II) in air and hydrogen at 200, 350, and 500°C and the composition and properties of the thermolysis products are considered.
The oxidative thermolysis of the complexes yields mixtures of cobalt and copper oxides, including mixed ones. The reductive
thermolysis of the complexes yields a Co + Cu bimetallic powder in the case of compound I and a Co + Cu + C powder in the
case of compound II. The thermal behavior of the complexes is governed by the nature of the ligand coordinated to the copper
atom. The observed data are explicable in terms of the properties of this ligand. The chemistry of the oxidative and reductive
thermolysis is discussed.
Original Russian Text ? D.P. Domonov, S.I. Pechenyuk, N.L. Mikhailova, A.T. Belyaevskii, 2007, published in Zhurnal Neorganicheskoi
Khimii, 2007, Vol. 52, No. 7, pp. 1104–1110. 相似文献
13.
Bambar Davaasuren 《Journal of solid state chemistry》2009,182(6):1331-5692
The lanthanum iron carbide La3.67[Fe(C2)3] was prepared from the elements by argon arc-melting followed by annealing. The crystal structure of the ternary phase was reported previously (space group P63/m with a=878.7(2) pm, and c=535.1(1) pm) [A.M. Witte, W. Jeitschko, Z. Naturforsch. 51b (1996) 249-255]. In the present work the compound was reinvestigated by X-ray powder and single crystal diffraction, and was further characterized by metallographic methods and chemical analyses. Our diffraction data clearly reveal a superstructure with weak superstructure reflections in the space group P63/m with a=879.26(8) pm and c=1604.59(15) pm, thus tripling the previously reported subcell. The crystal structure (refinement to R1=0.044 and wR2=0.075 for 1387 unique reflections and 60 variables) contains Fe(C2)3 trigonal planar groups with the C2 ligands bonded end-on to the Fe atoms. The C-C distance is typical for a double bond. La atoms as the least electronegative component surround the complex anions and form a framework of face-sharing tricapped trigonal prisms. The resulting hexagonal channels at 0, 0, z of the partial structure with chemical composition La3FeC6 are occupied by four additional La atoms per unit cell. These La atoms are fully ordered within a linear chain and display a Peierls-like distortion pattern. However, no long-range order in the a−b plane has been observed due to the random orientation of the chains. Because of the two different orientations which are possible for each chain the situation is similar to an Ising model on a triangular lattice. 相似文献
14.
The RPX2·AlX3 complex () reacts with unsaturated ketones and imines to give novel 7-oxa and 7-aza-2-phosphabicyclo[2.2.1]heptanes (compounds and respectively).A new 1,3-dipolar addition of (CH3)2 CCH2P?XR to nArN=C=S was disclosed resulting in the formation of the 2-imino-1,3-thiaphospholanes (). 相似文献
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The C26-C29 cyclopentenophenanthrenes - have been identified as widespread constituents of sediments and petroleums. They are long term degradation products of sterols in the subsurface 相似文献
16.
Vesa Rauhala 《Tetrahedron》2004,60(41):9199-9204
A new short strategy to prepare the spiroketal fragment of calyculins is presented. A novel Seyferth-Gilbert type homologation of hindered lactols to the corresponding alkynes has been achieved for the first time. The spirocyclization was achieved efficiently via a DIHMA (double intramolecular hetero-Michael addition) process of this hindered ynone. The spirocyclization rate is not dependent on the stereochemistry of the alkoxy substituent in the oxolane ring. 相似文献
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V. V. Sharutin V. S. Senchurin O. K. Sharutina B. B. Kunkurdonova 《Russian Journal of General Chemistry》2011,81(11):2235-2241
Complexes [Ph3MeP]3[Sb3I12]Me2C=O (I), [Ph3MeP]3[Sb2I9] (II), and [Ph3MeP]2[SbI5] (III) were obtained via the reaction of triphenylphosphonium iodide with antimony triiodide in acetone in 1:1, 3:2 and 2:1 molar
ratios. Reaction of the complex III with antimony triiodide (1:1) affords [Ph3MeP]3[Sb3I12] (IV). The structure of the obtained complexes was confirmed by X-ray analysis. 相似文献
18.
A new high yield synthesis of K2[99TcF6] is given. It is based on eqn (1) and uses 40% aqueous HF as solvent. [99TcBr6]2? + 6F? + 6Ag+ → [99TcF6]2? + 6AgBr (1) 相似文献
19.
High pressure vapour-liquid equilibrium data for the C2H6 + N2, C2H4 + N2, C3H8 + N2, and C3H6 + N2 systems are presented. The data are obtained isothermally in the range from 200 K to 290 K. For each point of data, temperature, pressure and liquid and vapour phase mole fractions are measured.Values for the vapour phase mole fractions are calculated from the obtained pressure, temperature and liquid phase mole fractions. The calculated values are compared with the experimental results, and it is found that the average mean deviation between calculated and experimental mole fractions is less than 0.009 for the systems considered in this work. 相似文献
20.
The rates of the thermal reaction of the nickel(0) complex Ni[P(C2H5)3]4 with the alkyl halides CH3Br, CH3I in toluene have been compared with those of the reactions of the nickel(I) complexes Ni(X)[P(C2H5)3]3 (X Br,I). The organic products from CH3X are methane and ethane, and those from C2H5I are ethane and ethylene. The reactivity of the nickel(I) complexes is 10–20 times less than that of the nickel(0) complex. The result suggest that the first step of the reaction of nickel(0) with CH3I is the expected oxidative addition of the halide to the metal substrate. The intermediate thus formed decomposes to produce ethane (and small amounts of methane) without further reaction with the organic halide. This mechanism is supported by deuterium-labeling experiments. 相似文献