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1.
The tin-containing sulfide Me3Sn(CH2)3-S-C6H5CH3-4 obtained by photoaddition of 4-toluene- thiol to allyltrimethyltin was oxidized with hydrogen peroxide to synthesize the tin-containing sulfone Me3Sn(CH2)3-SO2-C6H4CH3-4, the tin and sulfur atoms in which are separated by a trimethylene bribge. Treatment of the sulfone with butyllithium gave a first tin-containing lithium salt having a red-brown color. The exchange reaction of this salt with methyl iodide resulted in formation of two new isomeric tin-containing sulfones Me3SnCH2CH2CH(CH3)-SO2-C6H4CH3 and Me3Sn(CH2)3-SO2-C6H4CH2CH3 identified by 1HNMR spectroscopy. The latter result implies that the tin-containing sulfone is lithiated both by the methylene group adjacent to the sulfonyl group and by the toluene methyl group.  相似文献   

2.
Reactions of Uranium Pentabromide. Crystal Structures of PPh4[UBr6], PPh4[UBr6] · 2CCl4, (PPh4)2[UBr6] · 4CH3CN, and (PPh4)2[UO2Br4] · 2CH2Cl2 PPh4[UBr6] and PPh4[UBr6] · 2CCl4 were obtained from UBr5 · CH3CN and tetraphenylphosphonium bromide in dichloromethane, the latter being precipitated by CCl4. Their crystal structures were determined by X-ray diffraction. PPh4[UBr6]: 2101 observed reflexions, R = 0.090, space group C2/c, Z = 4, a = 2315.5, b = 695.0, c = 1805.2 pm, β = 96.38°. PPh4[UBr6] · 2CCl4: 2973 reflexions, R = 0.074, space group P21/c, Z = 4, a = 1111.5, b = 2114.2, c = 1718.7 pm, β = 95.42°. Hydrogen sulfide reduces uranium pentabromide to uranium tetrabromide. Upon evaporation, bromide is evolved from solutions of UBr5 with 1 or more then 3 mol equivalents of acetonitrile in dichlormethane yielding UBr4 · CH3CN and UBr4 · 3CH3CN, respectively. These react with PPh4Br in acetonitrile affording (PPh4)2[UBr6] · 4CH3CN, the crystal structure of which was determined: 2663 reflexions, R = 0.050, space group P21/c, Z = 2, a = 981.8, b = 2010.1, c = 1549.3 pm, β = 98.79°. By reduction of uranium pentabromide with tetraethylammonium hydrogen sulfide in dichloromethane (NEt4)2[U2Br10] was obtained; (PPh4)2[U2Br10] formed from UBr4 and PPh4Br in CH2Cl2. Both compounds are extremely sensitive towards moisture and oxygen. The crystal structure of the oxydation product of the latter compound, (PPh4)2[U02Br4]· 2 CH2Cl2, was determined: 2163 reflexions, R = 0.083, space group C2/c, Z = 4, a = 2006.3, b = 1320.6, c = 2042,5 pm, β = 98.78°. Mean values for the UBr bond lengths in the octahedral anions are 266.2 pm for UBr6-, 276.7 pm for UBr62? and 282.5 pm for UO2Br42?  相似文献   

3.
AsPh4[W2Cl4(N3S2)3] · CCl4; Synthesis and Crystal Structure The title compound was obtained in form of black crystals along with other products by the reaction of H2S and AsPh4[WCl4(N3S2)] in dichloromethane and subsequent addition of CCl4. Its crystal structure was determined by X-ray diffraction (3036 observed reflexions, R = 0.051). Crystal data: triclinic, space group P¯1, Z = 2, a = 1369, b = 1398, c = 1441 pm, α = 64.8, β = 68.02 and γ = 58.1°. The compound consists of AsPh4 ions, CCl4 molecules and [W2Cl4(N3S2)3]? ions. In the latter, one tungsten atom is member of one planar WN3S2 ring while the second tungsten atom belongs to two such rings forming a nearly planar S2N3WN3S2 unit. Two nitrogen atoms of this unit are linked to the other tungsten atom forming a WN2W ring. Two chloro ligands at each tungsten atom complete the coordination sphere to coordination numbers of six.  相似文献   

4.
α,ω-Alkane-bis-diphenylarsines and -dimethylarsines, R2AsCnH2nAsR2, may be obtained from dichloroalkanes and sodium diorganyl-arsenides, R2AsNa. The latter are prepared from tetraphenyl- and tetramethyl-diarsenic-sulphide, respectively, (R2As)2S. Elemental sodium eliminates on each As atom of the tetraphenyl-diarseno-alkanes one phenyl group, and on oxidation α,ω-alkane-diphenylarsenic acids are obtained. Reduction of these acids by means of SO2 yields cyclic, secondary arsenic oxides, whereas H3PO2 gives cyclic arsines with As ? As bonds. Disodium-phenylarsenide, C6H5AsNa2, prepared from (C6H5AsS)4, reacts with longer dichloroalkanes to form cyclic tertiary phenylarsines which may contain, in addition to As, further heteroatoms such as N, O or S. Those arsines, which only contain carbon as the ring atoms, commutate with AsCl3 to 1-chloro-arsolane and 1-chloroarsenane.  相似文献   

5.
New Nitrosyl Complexes of Rhenium: ReCl3(NO)2, ReCl3(NO)2(CH3CN), AsPh4[ReCl4(NO)2] ReCl3(NO)2, which is associated via chlorine bridges, was obtained in quantitative yield from rhenium pentachloride and trichloro nitromethane. Using acetonitrile, the monomer complex ReCl3(NO)2(CH3CN) can be obtained from it, from which AsPh4[ReCl4(NO)2] arises with tetraphenylarsoniumchloride. The i.r. spectra are reported and assigned. The crystal structures were determined for the latter two compounds with the help of X-ray diffraction data. ReCl3(NO)2(CH3CN) crystallizes in the monoclinic space group P21/n with four molecules per unit cell, AsPh4[ReCl4(NO)2] crystallizes in the tetragonal space group P4/n with two formula units. In all three compounds, the two NO groups linked to a Re atom are arranged cis to one another. As the anion in AsPh4[ReCl4(NO)2] is situated on a fourfold axis, the cis-configuration causes a statistical disorder in the crystal.  相似文献   

6.
The main fragmentation pathways of the N-1, C-2 and C-4 stereoisomers of the 1,2-dimethyl-4-R-transdecahydroquinoline-4-ol N-oxides (R=C?CH, CH?CH2 and C2H5) under electron impact are discussed. The correlation between the mass spectrometric chromatographic behaviour and the configuration of polar groups in the N-oxides examined is discussed. The mass spectra of the N-1 stereoisomers may be subdivided into two groups, depending only on the orientation of N→O group and not of the 4-OH group. The spectra of N-oxides with the axial N-oxide group reveal less intense ions and much more intense [M? CH3]+, [M? O]+, [M? OH]+ and ions, whereas in the spectra of their equatorial epimers the abundance of the ions exceeds the intensities of the latter ions.  相似文献   

7.
The o.formylarylazomethylenetriphenylphosphoranes carrying an electron withdrawing group on the ylidic carbon undergo thermal intra molecular cyclization to 3-oxo-indazolin-2-yl-methylenetriphenylphosphorane derivatives. The latter compounds, and their 1-alkyl derivatives, in turn, undergo thermal and/or acid catalyzed rearrangement to 4-oxo-l,4-dihydroquinazoline derivatives and PPh3. Some possible reaction mechanisms are discussed, and some synthetic applications of the above reactions are shown.  相似文献   

8.
Cs[Ag4Zn2(SCN)9]     
Caesium tetrasilver dizinc nona­thio­cyanate, Cs[Ag4Zn2(SCN)9], forms a continuous structure, where the Ag atoms and the S atoms of the thio­cyanate groups form chains which run along [101]. These chains are bonded together through the Cs and Zn atoms. It is not possible to distinguish between space groups P1 and P, but, if the latter space group is correct, the structure contains a thio­cyanate group disordered across a centre of inversion. The structure is described in space group P, in which the Cs atom also lies on a centre of inversion.  相似文献   

9.
Our systematic studies on quaternary thioborates containing both a comparably small alkali metal ion and a large alkaline earth cation lead to the two new crystalline phases KBa4(BS3)3 and K4Ba11(BS3)8S. The former consists of isolated BS3 units and the corresponding counter‐ions while in the latter BS33– and S2– anions coexist. In both compounds boron is found in a trigonal‐planar coordination, in the case of K4Ba11(BS3)8S the additional sulfide anions are located inside an octahedron built of six barium cations. The two compounds were prepared in solid state reactions from the metal sulfides, amorphous boron and sulfur. Evacuated carbon coated silica tubes were used as reaction vessels since temperatures up to 870 K were applied. KBa4(BS3)3 crystallizes in the monoclinic space group C 2/c (no. 15) with a = 14.299(6) Å, b = 8.808(3) Å, c = 13.656(5) Å, β = 98.72(4)°, and Z = 4, while for K4Ba11(BS3)8S the trigonal space group R 3 c (no. 167) was found with a = 18.146(3) Å, c = 25.980(7) Å, and Z = 6. X‐ray powder patterns are compared to calculated diffraction data obtained from single crystal X‐ray structure determination, in the case of K4Ba11(BS3)8S vibrational spectra were recorded.  相似文献   

10.
The base-catalyzed isomerization of 4-arylamino- and 4-morpholino-2-sulfolenes to 3-substituted 2-sulfolenes was investigated by UV spectroscopy. A shift in the as frequencies of the SO2 group was noted in the IR spectra of the latter.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 627–630, May, 1975.  相似文献   

11.
The electronic structures of the oxides P4O6 and P4O10 are calculated by the self-consistent molecular orbital method including all valence electrons and the 3d orbitals on phosphorus. It is found that the former molecule appears to be virtually non-polar whilst in the latter, the P-O (terminal) bonds are highly polar. The bond order matrix shows that the internal P-P bonding in the P4 unit is not marked.  相似文献   

12.
The salt [(CH3)4N]2[Sb6O4(NCS)12] is the first identified thiocyanato-oxy-antimonate(III) complex. Reported are details of the synthesis, relevant infrared data and its x-ray structure. The compound crystallizes in the triclinic space group P1 with Z = 2 (C10H12N7O2S6Sb3) and unit cell dimensions a = 11.314(6), b = 12.846(3), c = 8.679(2) Å; α = 91.93(3)°, β = 90.31(3)° and γ = 99.13(3)°. It contains centrosymmetric [Sb6O4(NCS)12]2? anions packed with isolated tetramethyl-ammonium cations. The fundamental structural element of the anion is provided by the fusion of three SbOSbO rings forming a zig-zag portion of a ribbon, only slightly pleated. Peculiar is the unequivalence of the six thiocyanate ligands, though all primarily N-bonded to antimony atoms. Three thiocyanates are terminal while other three are asymmetrically N-bridging between two centers; two of this latter type are also interconnecting the anions via Sb???S contacts. There are three different antimony environments, the primary bonding at Sb being to one nitrogen and three oxygens, to one oxygen and three nitrogens and to two atoms of each type.  相似文献   

13.
4-(3-Alkylureido)-2, 2, 6, 6-tetramethylpiperidine-1-oxyls are rapidly oxidized by N2O4 or NOCl to 4-(3-alkylureido)-2, 2, 6, 6-tetramethyl-1-oxopiperidinium nitrates and chlorides, which are then nitrosated to 4-(3-alkyl-3-nitrosoureido)-2, 2, 6, 6-tetramethyl-1-oxopiperidinium salts. The perchlorates of the latter were prepared by an exchange reaction with HClO4. The nitrosation of alkylureidooxoammonium salts is the first example of chemical modification of oxoammonium derivatives in which the highly reactive >N+=O group is inert toward the reagent.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 542–547, March, 1993.  相似文献   

14.
Reactions of hydrated ruthenium chloride with 2-methyl-3-hydroxy-4-pyranone, ethylmaltol (etmaltH) and with 1,2-dimethyl-3-hydroxy-4-pyridinone (dmppH) are described. The former results in the formation of Ru(etmalt)3, but the course of the latter depends on conditions, producing the earlier-characterised Ru(dmmp)3Cl in ethanol–water solution, Ru(dmmp)3 in aqueous solution under mild conditions, and Ru(dmpp)2(H2O)2 after extended refluxing. EXAFS studies established ruthenium-oxygen distances in Ru(etmalt)3 and in Ru(dmmp)· 6H2O. Solubilities of Ru(dmmp)3 in methanol–water mixtures reveal greater solubility in methanol than in water, and indications of a modest solubility maximum, and thus synergic solvation, in methanol-rich mixtures.  相似文献   

15.
We report on the luminescence of doped and undoped PbMoO4 and PbWO4 single crystals; a red emission is found for the first time for PbMoO4. The degree of polarization of both the emissions of PbWO4 and of the shorter-wavelength emission of PbMoO4 is measured. The shorter-wavelength emissions are assigned to the 3T11A1 transition in the tetrahedral MoO42?(WO42?) group. It is assumed that the 3T1 level is split due to spin-orbit coupling. The longer-wavelength emissions are assigned to a transition in a molybdate (tungstate) group lacking an oxygen ion, i.e., a MoO3(WO3) group.  相似文献   

16.
The crystal structure of LiEu3O4 which represents a new structure type was solved by usual methods with the aid of integrated WEISSENBERG photographs (MoKα radiation, 787 reflexions) and refined to a reliability index of 4.3%. In LiEu3O4 just as in the first known europium(II, III)-oxide, Eu3O4, a clear distinction is possible between the divalent and trivalent europium ions. The given assignment which is based on crystal chemical arguments has been verified indirectly by means of the isostructural compound LiSr2EuO4, the cation distribution of which was established experimentally. The structure of LiEu3O4 is discussed in connection with the related oxides EuO and Eu3O4. The geometrical relations to the latter are of special interest, as LiEu3O4 undergoes a topotactical transformation into Eu3O4 by heating it in a high vacuum. There is an astonishing close structural relationship between LiEu3O4 and Yb3S4: except for lithium all the atoms are correlated as for isostructural compounds.  相似文献   

17.
A number of compounds of the type oftrans-4-FC6H4Pt(PAr3)2SC6H4F-4, where Ar is a substituted phenyl group, have been prepared starting from the corresponding chlorides. By exchange reactions oftrans-4-FC6H4Pt[P(C6H4F-4)3]2SC6H4F-4 with the above-mentioned compounds or Ar3P,trans-4-FC6H4Pt[P(C6H4F-4)3][PAr3]SC6H4F-4 have been generated in solution. For the latter compounds, the effect of Ar3P oncis- andtrans-ligands has been studied by the19F NMR technique. It has been shown that thecis- andtrans-effects of Ar3P run parallel and are well described by pK a values and ionization potentials of the unshared electron pair in Ar3P, as well as by 0 constants of the aryl groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1359–1363, July. 1995.  相似文献   

18.
Synthesis of 2-Hydroxy-3-methyl-2-hexen-4-olid The title compound 13a, a substance used in food-flavoring, was synthesized in 89% overall yield, starting from methyl 2-hydeoxy-3-butenoate (3a). The key step in this transformation is the isomerization of the C?C bond in 3a which yielded methyl 2-oxobutanoate as an intermediate. The latter underwent a self-condensation yielding 2-hydroxy-4-(methoxycarbonyl)-3-methyl-2-hexen-4-olid ( 11 a), which, after hydrolysis and decarboxylation, gave 13 a. In addition, the syntheses of five other compounds related to 13 a are reported.  相似文献   

19.
[{Cp(CO)3Mo}4In4(PSiMe3)4], an Organometallic In4P4-Heterocubane [{Cp(CO)3Mo}InCl2] reacts with P(SiMe3)3 in THF as solvent to form [{Cp(CO)3Mo}4In4(PSiMe3)4] 1. 1 crystallizes in the space group P1 . The lattice constants (at 208 K) are: a = 1 770.1(6), b = 1 490.3(6), c = 1 317.5(6) pm, α = 76.59(4),β = 88.54(3), γ = 88.98(3)°. According to the crystal structure analysis, 1 contains a slightly distorted In4P4-core with an alternating arrangement of In and P atoms. The In atoms are coordinated roughly tetrahedrally by three PSiMe3 groups (In–P: 256.9(3)–262.3(3) pm) and a {Cp(CO)3Mo} substituent (In? Mo: 278.0(2)–279.5(3) pm).  相似文献   

20.
This compound is obtained in several ways, at 900°C, from the components of the FePO system when the oxygen pressure is made suitable, or from Fe3(PO4)2 + Fe + Fe2O3 in a sealed tube under vacuum. It crystallizes under these latter conditions with a trace of FeCl2. The cell is monoclinic; a = 6.564(1), b = 11.271(2), c = 9.383(2) Å, β = 103.95 (2)°, with Z = 4, group P21c. The structure is determined thanks to the use of a direct method and Fourier synthesis and is refined to R = 0.033. The PO4 tetrahedra are isolated; the iron fills four crystallographic sites: three are more or less distorted octahedra, the fourth is a trigonal bipyramid. The oxyphosphate character is ascertained by the presence of some oxygen atoms connected to iron only, with, moreover, a low site potential. This compound is paramagnetic above 90°K. Its Mössbauer spectrum exhibits four doublets in good agreement with the structure; in order to identify which one corresponds to the hexahedral site, the phase Fe3Zn(PO4)2O has been prepared, but its Mössbauer spectrum, in spite of the zinc affinity for the V coordination, shows that two sites are modified, which does not allow conclusions to be made.  相似文献   

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