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1.
A seven-step synthesis ofS-(+)-hydroprene (S-1) in 20 % overall yield starting fromS-(+)-3,7-dimethyl-1,6-octadiene (2) of 55+-10 % optical purity is described. The introduction of an optical enhancement step in the synthetic sequence at the stage ofS-(–)-3,7-dimethyl-1-octanol (9) raises the optical purity ofS-1 from 50 % to 80 %.For part 13, see. ref.1 Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 342–348, February, 1993.  相似文献   

2.
The condensation of diacetylmonoxime (damnx) with morpholine N-thiohydrazide (mth) in 1:1 molar ratio in ethanol (16 h) afforded a nitrogen–sulfur zwitterionic heterocyclic compound, N-(3,4-dimethyl-1,2,5-thiadiazole-2-ium-2-yl)morpholine-4-carbothioate (dtmc). However, the same reaction in presence of [Zn(OAc)2]·2H2O in ethanol under gentle reflux on (3 h) yielded the zinc complex, [Zn(Hdammthiol)(OAc)(H2O)]·H2O, where H2dammthiol (H2L2) is the thiol form of tridentate NNS donor thiohydrazone ligand, diacetylmonoxime morpholine N-thiohydrazone (Hdammth). Both the nitrogen–sulfur heterocyclic compound and the zinc complex have been characterized by elemental analyses, spectroscopy (IR, UV–Vis, 1H NMR and 13C NMR) and single crystal X-ray crystallography. It is noteworthy that the heterocyclic compound shows SS interaction with distance 2.738 Å in its planar conformation. The heterocyclic compound forms two dimensional supramolecular sheets through C–HO and ππ interactions while the zinc complex, with distorted square pyramidal geometry, forms 1D supramolecular chain. A mechanism has been proposed for the formation of nitrogen–sulfur heterocyclic compound.  相似文献   

3.
The preparation and some properties of the cobalt(II) complexes Co(LH2)Cl2·2H2O, Co(LH2(NCS)2 and CoL·H2O (whereLH2=N,N-(dipicolyl)-1,8-naphthylenediamine) are reported. On the basis of magnetic moments, visible reflectance and IR data, the structure is proposed to be pseudo-octahedral for Co(LH2)Cl2·2 H2O, pseudo-tetrahedral for Co(LH2)(NCS)2 and square planar for CoL·H2O.
Deprotonierte und Nicht-deprotonierte Co(II)-Komplexe des vierzähnigen Bisamid-Liganden N,N-(Dipicolyl)-1,8-naphthyldiamin. Drei verschiedene Koordinationstypen
Zusammenfassung Es werden die Darstellung und einige Eigenschaften der Kobalt(II)-Komplexe Co(LH2)Cl2·2 H2O, Co(LH2)(NCS)2 und CoL·H2O [LH2=N,N-(dipicolyl)-1,8-naphthylendiamin] diskutiert. Auf der Grundlage von magnetischen Momenten, von Daten der sichtbaren Reflektions-und IR-Spektren wird eine pseudooctaedrische Struktur für Co(LH2)Cl2·2H2O, eine pseudotetraedrische für Co(LH2)(NCS)2 und eine planar-quadratische für CoL·H2O vorgeschlagen.
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4.
Potentially bi- and tetra-dentateSchiff bases derived from salicylaldehyde react with hydrated uranyl salts to give complexes: UO2H2 LX 2, UO2H2 LX 2 and UO2(HL)2 X 2 [H2 L=N,N-propane-1,3-diylbis(salicylideneimine), H2 L=N,N-ethylenebis(salicylideneimine) and HL=N-phenylsalicylideneimine;X =Cl, Br, I, NO3 , ClO4 , and NCS]. Because of marked spectral similrities with the structurally known Ca(H2 L) (NO3)2, theSchiff bases are coordinated through the negatively charged phenolic oxygen atoms and not the nitrogen atoms of the azomethine groups which carry the protons transferred from phenolic groups on coordination. Halide, nitrate, perchlorate and thiocyanate groups are covalently bonded to the uranyl ion, resulting a 6-coordinated uranium ion in the halo and thiocyanato complexes and 8-coordinated in nitrato and perchlorato complexes.
Komplexe von Dioxouranyl(VI) mit zwitterionischen Formen von zwei- und vierzähnigen Schiff-Basen
Zusammenfassung Von Salizylaldehyd abgeleitete zwei- und vierzähnigeSchiff-Basen reagieren mit hydratisierten Uranylsalzen zu Komplexen folgenden Typs: UO2H2 LX 2, UO2H2 LX 2 und UO2(HL)2 X 2 [H2 L=N,N-Propan-1,3-diylbis(salicylidenimin), H2 L=N,N-Ethylen-bis(salicylidenimin) und HL=N-Phenylsalicylidenimin;X =Cl, Br, I, NO3 , ClO4 und NCS]. Auf Grund eindeutiger spektraler Ähnlichkeiten mit dem bekannten Ca(H2 L) (NO3)2 wird auf Koordination über die negativ geladenen phenolischen Sauerstoffatome (und nicht über die Azomethin-Stickstoffe) geschlossen. Die AnionenX sind kovalent an das Uranyl-Ion gebunden; damit ergibt sich ein hexakoordiniertes Uranyl-Ion für die Halogen- und Thiocyanat-Komplexe und Oktakoordination für die Nitrat- und Perchlorat-Komplexe.
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5.
A new compound from the series of alkoxyketoiminates, Cu(II) bis-(2-methoxy-2,6-dimethyl-3-imino-5-heptanonate), has been synthesized and studied by X-ray crystallography. Crystal data for CuO4N2C20H36: a=10.154(1), b=9.921(1), c=11.684(2) , =96.17(1)°, space group P21/c, Z=2, dcalc =1.226 g/cm3, R=0.037. The structure is molecular and built from isolated trans-complexes. The copper atom has a plane square environment of two oxygen atoms (Cu–O 1.93 ) and two nitrogen atoms (Cu–N 1.90 ). The O–Cu–N chelate angle is 91.7°. The complex has an intramolecular hydrogen bond, N–H...O 2.16 , involving the alkoxy oxygen atom. The molecular packing in the crystal is close to that of copper(II) dipivaloylmethanate. The calculated van der Waals intermolecular interaction energies and thermogravimetric characteristics of the complexes are compared.  相似文献   

6.
Gas-phase reaction of acetylene with HgCl2 resulting in -chlorovinylmercury derivatives and their interaction with Cl and I anions and KI molecule was studied by the ab initio MP2 method with the Dunning—Hay double zeta basis set and LanL pseudopotential for Hg, K, and I atoms. The reaction was shown to proceed via a -complex of acetylene and HgCl2 (the calculated enthalpy of formation is –6.5 kcal mol–1). According to calculations, the activation energy of formation of cis--chlorovinylmercury chloride from acetylene and HgCl2 is 31 kcal mol–1. Chloride and iodide anions and KI molecule are readily added to both cis- and trans-isomer of -chlorovinylmercury chloride to give stable species.  相似文献   

7.
The effects of anti-symmetric electrolytes (CaCl2, Ca(SCN)2, MgCl2, and/or Mg(SCN)2) and pH on the phase behavior, the -potential, the hydrodynamic diameter and the surface charge density of an oil-inwater type (O/W-type) microemulsion formed in solutions of an amphoteric surfactant (N ,N -dimethyl-N -lauroyllysine, DMLL)/n-octane/1-pentanol/brine have been examined. The formation of the microemulsion in the presence of CaCl2 and/or Ca(SCN)2 is of Winsor-type with an increase in the concentration of 1-pentanol. Particularly, microemulsion is not formed by the addition of Ca(SCN)2 in a pH region less than 2.6. The -potential and the surface charge density of the microemulsion in the presence of CaCl2 decrease with an increase in pH and show slightly positive values in the isoelectric region (pH 5-7), while, in the presence of Ca(SCN)2, the -potential and the surface charge density show negative values in the same region at which the net charge of DMLL molecules becomes almost zero. The hydrodynamic diameters in the presence of CaCl2 show a maximum value around pH 2.5, whereas, in the presence of Ca(SCN)2, the minimum value is around pH 5.5. Similar tendencies are recognized in results for the -potential, the hydrodynamic diameter and the surface charge density of the O/W-type microemulsion in the presence of MgCl2 and Mg(SCN)2. A new formula to estimate the binding constants (K) of Ca2+, Mg2+, Cl, and SCN to the hydrophilic groups in DMLL molecules and the adsorption density of DMLL molecules on the oil/water interface (N) in the presence of antisymmetric electrolytes has been derived.K for Ca2+, Mg2+, Cl, and SCN was found to beK Ca=0.12M–1,K Mg=0.14 M–1,K Cl=0.0084±0.0016 M–1, respectively.N for DMLL molecules in the presence of CaCl2, Ca(SCN)2, MgCl2 and/or Mg(SCN)2 was found to be 0.50 nm–2, 0.38 nm–2, 0.44 nm–2, and 0.47 nm–2, respectively; and the surfactant (DMLL) numbers per O/W-type microemulsion droplet change from a few hundreds to a few thousands with changing pH. The larger the hydrodynamic diameter of the O/W-type microemulsion, the greater the number of DMLL molecules adsorbed on the O/W-type microemulsion surfaces.  相似文献   

8.
Bifunctional sulfides and sulfoxides containing carboxy, carbamoyl, or acylamino groups in the -position are synthesized, and their IR spectra were studied. An unusual decrease in the frequencies of the carbonyl vibrations (by 20–34 cm–1) was found for thiodipropionic acid, its amides, and bis(-acylaminoethyl) sulfides by comparison with the corresponding sulfoxides. The low-frequency shift of the CO band in these carbonylsulfides was not, as expected, associated with the intramolecular S...O coordination, since the x-ray structural investigation of thiodipropionic acid and bis(2-trifluoroacetylaminoethyl) sulfide did not show short intra- and intermolecular contacts involving the sulfur atom. Both structures contain intermolecular hydrogen bonds (C=O...HO or C=O...HN).For previous communication, see [1].A. N. Nesmeyanov Institute of Heteroorganic Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1766–1775, August, 1992.  相似文献   

9.
The AMI calculations of hydrocarbon molecules C20H10 (1) and C30H10 (2) and anions C20H15 –4 (3) and C30H15 (4) have been performed with the full energy optimization of the geometric parameters. The chosen topology of the carbon framework of the studied compounds is identical to the topology of the corresponding carbon fragments of C60 fullerene. Analysis of the structure of the frontier orbitals of systems1–4 demonstrated that the tendency of the C20H10 molecule to form sandwich -complexes of the 5-type with transition metal atoms is small; however, this tendency is significantly larger than that of C30H10. Moreover, the exclusion of the five-membered cycle of bowlshaped unsaturated hydrocarbon molecules and anions from the conjugated system (as a result of the conversion of five framing C atoms to saturated carbon centers) favors the stabilization of their 5-type -complexes with M(C5H5) species. The stability of these complexes must approach the stability of classical sandwich complexes of the ferrocene type. The results obtained have been extrapolated to polyhedral C60 and C70 carbon clusters.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 855–858, May, 1995.This work was financially supported by the Russian Foundation for Basic Research (Projects No. 93-03-4101 and 93-03-18725).  相似文献   

10.
A new highly selective thiocyanate electrode based on N,N-bis-(furaldehyde)-1,2-phenylenediamine-dipicolyl copper(II) complex [Cu(II)-BFPD] as neutral carrier is described. The electrode has an anti-Hofmeister selectivity sequence: SCN>I>Sal>ClO4 >Br>NO2 >Cl>NO3 >SO4 2–>SO3 2–>H2PO4 and a near-Nernstian potential linear range for thiocyanate from 1.0×10–1 to 5.0×10–6 mol L–1 with a detection limit 2.0×10–6 mol L–1 and a slope of 57.5 mV decade–1 in pH 5.0 of phosphate buffer solution at 20 °C. The response mechanism is discussed on the basis of results from A.C. impedance measurement and UV spectroscopy. The anti-Hofmeister behavior of the electrode results from a direct interaction between the central metal and the analyte ion and a steric effect associated with the structure of the carrier. The electrode has the advantages of simplicity, fast response, fair stability and reproducibility, and low detection limit. The selectivity of electrodes based on [Cu(II)-BFPD] exceeds that of classical anion-sensitive membrane electrodes based on ion exchangers such as lipophilic quaternary ammonium or phosphonium salts. Application of the electrode for determination of thiocyanate in waste water samples from a laboratory and a gas factory, and in human urine samples, is reported. The results obtained were fair agreement with the results obtained by HPLC.  相似文献   

11.
The general thermochemical reaction LnCl3·6H2O(c)+3Hthd(1)+73.92H2O(1) = Ln(thd)3(c) +3HCl·26.64H2O(aq); rHm (Ln = Pr, Ho and thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) was employed to determine through solution-reaction calorimetry at 298.15 K the standard molar enthalpies of formation of crystalline chelates, –2434.3±11.5 (Pr) and –2384.8±11.5 (Ho) kJ mol–1. These values and the corresponding molar enthalpies of sublimation enabled the determination of the standard molar enthalpies of chelates in the gaseous phase. From these values the mean enthalpies of the lanthanide-oxygen bond, 265±10 (Pr) and 253±10 (Ho) kJ mol–1 were calculated.  相似文献   

12.
The anion-exchange properties of a new organomineral sorbent obtained by modification of clinoptilolite-containing tuffs by polyhexamethyleneguanidine have been studied after different periods of storage (time after synthesis) and numbers of sorption-regeneration cycles. The sorbent can be used as a cation- and an anion-exchanger simultaneously. Selectivity coefficients (exchange constants) for F, SO4 2–, and HPO4 2– ionsvs. Cl ions on modified clinoptilolite-containing tuffs have been determined. The modification improves the mechanical properties of clinoptilolite tuffs.For part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1554–1556, September, 1994.  相似文献   

13.
The process of structurization in solutions of H-complexes of dimethyl 3,3,4,4 -benzophenonetetracarboxylate with 4,4 -diaminodiphenylmethane has been investigated in 90 % aqueous methanol in the concentration range 6 to 0.2 g L–1. Structural instability of the solutions has been found in the concentration range from 1.2 to 2 g L–1. The addition of an ionogenic substance stabilizes the solution and results in monotonic changes in the structural parameters as solution is diluted. A tendency toward variation of the extemum in the mean correlation radius of the polarizability fluctuation has been found in the concentration range 0.6-–1 g L–1, which had been observed previously for polymer systems.For Part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1219–1221, July, 1994.  相似文献   

14.
The reaction ofmeso- andD,L-forms of bis(cyclohexyl)-2,2-dione with a methanol solution of hydrogen peroxide in a neutral medium has been studied. It has been established that in the case of theD,L-formrac-(1R,4R,9S,10S)-1,4-dihydroxy-2,3-dioxatricyclo-[8.4.0.04,9] tetradecane is formed, while themeso-form affordsrac-(1R,4R,9S,10R)-1-methoxy-4-hydroxy-2, 3-dioxatricyclo[8.4.0.04,9]tetradecane. The structures of the compounds have been established by X-ray structural analysis and by1H and13C NMR spectroscopy.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 934–939, May, 1995.This work was financially supported by the International Science Foundation (Grant M04 000), the American Crystallographic Association, and the Russian Foundation for Basic Research (Project No. 94-03-09189).  相似文献   

15.
Summary The Schiff base ligand diethyl(ethylenebis--aminocrotonate) (LH2) reacts with lanthanide(III) chlorides and nitrates in various solvents to give solid complexes of the stoichiometriesLn(LH2)Cl3 (Ln=La–Yb),Ln(LH2)2Cl3 (Ln=La–Sm),Ln 2(LH2)3Cl6(Ln=Eu–Yb) andLn(LH2)(NO3)3 (Ln=La–Yb). Properties, conductivity measurements, X-ray powder patterns, thermal data, magnetic moments and spectroscopic (IR,1H-NMR, electronic diffuse reflectance and solid state emission f-f spectra) are discussed in terms of the nature of the bonding and the possible structural types.
Synthese und Charakterisierung der Komplexe von Lanthanid(III)chloriden und -nitraten mit der vierzähnigen Schiff-Base Diethyl(ethylenbis--aminocrotonat)
Zusammenfassung Der Schiffbasen-Ligand Diethyl(ethylenbis--aminocrotonat) reagiert mit Lanthanid(III)chloriden und -nitraten in verschiedenen Lösungsmitteln unter der Bildung von festen Komplexen der StöchiometrienLn(LH2)Cl3 (Ln = La – Yb),Ln(LH2)2Cl3 (Ln = La – Sm),Ln(LH2)3Cl6 (Ln = Eu – Yb) undLn(LH2)(NO3)3 (Ln = La – Yb). Die allgemeinen Eigenschaften, Leitfähigkeitsmessungen, Röntgen-Pulverdiagramme, thermische Daten, magnetische Momente und spektroskopische Daten (IR,1H-NMR, Elektronenreflexionsspektren und Festkörperemissions-f-f-Spektren) werden im Hinblick auf die Bildungsverhältnisse im Komplex und strukturelle Möglichkeiten diskutiert.
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16.
Photochemical reactions of M(CO)3(5-C9H7), where M=Mn (1) or Re (2), with indene have produced 2-indene complexes M(CO)2(2-C9H8)(5-C9H7), where M=Mn (3) or Re (4). Deprotonation of complex3 witht-BuOK in THF at –60 °C gives the anion [Mn(CO)2(1-C9H7)(5-C9H7) (5), in which there occurs a rapid interchange of the Mn(CO)2(5-C9H7) group between positions 1 and 3 in the 1-indenyl ligand. The reaction of complex4 with Ph3CPF6 in CH2Cl2 at 0 °C leads to the complex [Re(CO)2(3-C9H7)(5-C9H7)PF6, whereas the similar reaction of complex3 gives only decomposition products even at –20 °C.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1280–1285, July, 1993.  相似文献   

17.
Crystal structures of the - and -phase inclusion complexes of dianilinegossypol with acetone obtained at 20° and 30 °C, respectively, have been determined by X-ray structure analysis. Crystal data of the -phase complex are: C42H40O6N22C3H6O, orthorhombic, space group Pccn, a = 29.501(9), b = 10.866(2), c = 13.756(3) Å, V = 4409(1) Å3, Z = 4, D x = 1.18 g cm-3. The structure has been refined to a final R value of 0.117 for 1401 observed reflections. The host–guest ratio for the -phase complex is the same (1 : 2) and the crystals are monoclinic, space group C2/c, a = 28.352(6), b = 11.836(2), c = 13.196(1) Å, = 93.05(1)°, V = 4422(2) Å3, Z = 4, D x =1.18 g cm-3. The structure has been refined to a final R value of 0.077 for 1414 observed reflections.In both phases molecules of dianilinegossypol form hydrogen-bondedribbons by O(4)–-HO(3) H-bonds. Phases are determined by the same structural motif. In the -phase complex the cages are in the form of prisms but in the -phase clathrate they undergo a modification by shrinking in two directions and widening in one. Molecules of acetone are hydrogen bonded to the host molecules via aO(1)–-HO(G) bond and are accommodated in cavities for both complexes, i.e. both phases are cryptate-type inclusion complexes.Supplementary data relevant to this publicationhave been deposited with the British Library,No. SUP 82227 (24 pages).  相似文献   

18.
A convenient electrochemical method for the synthesis of 8,8-dihalogen derivatives of bis(1,2-dicarbollyl)cobalt(III) anion [8,8X2-3,3-Co(1,2-C2B9H10)] (X = Cl, Br, I) was developed. The method includes the electrolysis of a solution of alkaline metal halide and tetramethylammonium salt of bis(1,2-dicarbollyl)cobalt(III) in methanol at 50 °C in a one-compartment electrochemical cell with a nickel cathode and platinum anode.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2448–2451, November, 2004.  相似文献   

19.
Density functional (DFT) calculations have been performed on (3-allyl)palladium complexes with amines. The effects of the donor properties of amines on the structure of the complexes and electron density distribution have been analyzed. As the number of donor methyl groups increases in the series NH3–n (CH3) n , where n = 0, 1, 2, the Pd-C bond, which is in the trans position relative to the amine, becomes longer, leading to increased probability of an intraspheric attack of the amine on the appropriate terminal carbon atom of the allyl ligand; when n = 3, this tendency is violated.Original Russian Text Copyright © 2004 by O. Yu.Tkachenko and A. P. BelovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 442–444, May–June, 2004.  相似文献   

20.
Zusammenfassung Cu(I) bildet mit zahlreichen nicht lumineszierenden Thionoliganden (N-monosubstituierten N-Sulfonylthioharnstoffen, N,N-Dialkyl-N-phenylthioharnstoffen und N,N-Dialkylmonothiocarbamaten) rot lumineszierende oktaedrische Cluster (CuL)6. Die Lumineszenz tritt sowohl im Festzustand als auch in Lösungen auf. Abklingzeiten von 10–5s deuten auf kurzlebige Phosphoreszenz hin. Der Einfluß verschiedener Strukturelemente auf die Lage der Emissionsmaxima wird diskutiert. Dabei bewirken Veränderungen in der Metall-Ligand-Koordination die stärkste Verschiebung der Lumineszenzbanden. Tetraedrische (CuL)4-Cluster mit den obigen Thionoliganden zeigen keine Lumineszenz. Generelle Unterschiede in der Struktur oktaedrischer und tetraedrischer Cluster werden diskutiert.Ag(I) bildet nur mit N-Alkyl-N-sulfonylthioharnstoffen lumineszierende Cluster (AgL)6. Die Lumineszenz ist im Gegensatz zu den Cu-Clustern auf den Festzustand beschränkt.
Luminescent Cu(I) and Ag(I) clusters with thiono ligands
Summary Octahedrical (CuL)6 clusters with several non luminescent thiono ligands (N-monosubstituted N-sulfonylthioureas, N,N-dialkyl-N-phenylthioureas and N,N-dialkylmonothiocarbamates) show red luminescence in the solid state and in solution. The luminescence lifetimes of 10–5s are typical of short lived phosphorescence. The emission bands are affected by structural variation of the ligand. Changes of the coordination bonds cause the strongest shifts of the luminescence maxima. Tetrahedrical (CuL)4 clusters with the same thiono ligands are not luminescent. General structural differences between octahedral and tetrahedral clusters are discussed.(AgL)6 clusters are only luminescent in the solid state and if the ligand is a N-monosubstituted N-sulfonylthiourea
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