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1.
New inclusion complexes (C2H5)4N+HCO 3 ·(NH2)2CO·2H2O (1) and (n-C4H9)4N+HCO 3 ·3(NH2)2CO (2) have been prepared and characterized by X-ray crystallography. Crystal data, MoK radiation:1, space groupP21/n,Z=8,a=9.356(1),b=29.156(4),c=12.161(1) Å, =90.03(1)°,R F =0.062 for 2214 observed data;2, space groupP,Z=2,a=8.404(2),b=12.352(2),c=14.377(4) Å,a=88.20(2), =89.56(2), =71.68(1)°,R F =0.052 for 3092 observed data. In both compounds the tetraalkylammonium ions are sandwiched between puckered layers, which are constructed from [((NH2)2CO)2(HCO 3 )2], ribbons, each composed of centrosymmetric hydrogen-bonded urea dimers and bicarbonate dimers, by lateral linkage through water molecules in1, and by direct cross-linkage of an alternate, parallel arrangement of the urea/bicarbonate and complementary urea ribbons in2. Supplementary Data relating to this article have been deposited with the British Library as Supplementary Publication No. SUP 82201 (40 pages).  相似文献   

2.
The structures of the 1:2 molecular complexes of trans -9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with acetophenone (1), (C26H20O2·2 C8H8O) and with 3-methylcyclopentanone (2), (C26H20O2·2C6H10O) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P ,a =8.979(5) Å,b =9.316(3) Å,c = 11.12(1) Å, =94.40(6)°, = 106.53(6)°, = 109.92(5)°,V = 822.94 Å3,Z = 1,R = 0.097 for 2549 unique reflections. Compound (2):P ,a = 8.958(7) Å,b =9.815(4) Å,c = 9.807(4) Å, = 96.88(3)°, = 109.21(8)°, = 103.33(7)°,V = 774.10 Å3,Z = 1,R = 0.059 for 2494 unique reflections. The intermolecular arrangements in both structures are characterised by host-to-guest hydrogen bonding interactions. The thermal properties of compound (2) have been characterised by DTA and TGA thermograms.  相似文献   

3.
The electrochemical reduction of compounds with a common formula R1(H)C=C(CN)R2, where R1 is C6H5, n-CH3OC6H4, n-FC6H4, or -furyl; and R2 is CN or COOC2H5 is studied. The reduction of these compounds at a zinc cathode in the water–acetonitrile KH2PO4 solution yields both cyclic and linear hydrodimers. The relative yield of the linear hydrodimer increases with lowering the temperature and acetonitrile content in the catholyte. The obtained data well correlate with the suggestion that the cyclic products form in the catholyte bulk from linear hydrodimers.  相似文献   

4.
Summary New complexes of tin(II), silver([) and iron(II) withpara- andmeta-substituted benzeneseleninic acids are reported and studied by chemical analyses, spectroscopic methods, conductivity and magnetic measurements. The complexes, of the type Sn(XC6H4SeO2)2, Ag(XC6H4SeO2) and Fe(H2O)2(XC6H4SeO2)2, were obtained by reaction of SnCl2, · 2 H2O. AgNO3 and Fe(NH4)2(SO4)2·6 H2O with the sodium benzeneseleninates, XC6H4SeO2Na (X = H.p-Cl,m-Cl,p-Br,m-Br orp-Me). The i.r. spectral data suggest that the silver and iron complexes contain RSeO 2 ligands which act as bidentates in O,O-seleninato complexes. All the iron complexes have a distorted octahedralD 4h symmetry. The number of bands in the i.r. spectra of the tin derivatives indicates that there is no equivalence in the manner in which the two seleninato ligands are bonded. We could suggest that the tin atoms are intermolecularly O.O-bonded via one RSeO 2 group, whereas the second ligand is coordinated to the metal via one oxygen atom forming polymeric -tetrahedral derivatives.  相似文献   

5.
The synthesis, reduction, optical and e.p.r. spectral properties of a series of new binuclear copper(II) complexes, containing bridging moieties (OH, MeCO2 , NO2 , and N3 ), with new proline-based binuclear pentadentate Mannich base ligands is described. The ligands are: 2,6-bis[(prolin-1-yl)methyl]4-bromophenol [H3L1], 2,6-bis[(prolin-1-yl)methyl]4-t-butylphenol [H3L2] and 2,6-bis[(prolin-1-yl)methyl]4-methoxyphenol [H3L3]. The exogenous bridging complexes thus prepared were hydroxo: [Cu2L1(OH)(H2O)2] · H2O (1a), [Cu2L2(OH)(H2O)2] · H2O (1b), [Cu2L3(OH)(H2O)2] · H2O (1c), acetato [Cu2L1(OAc)] · H2O (2a), [Cu2L2(OAc)] · H2O (2b), [Cu2L3(OAc)] · H2O (2c), nitrito [Cu2L1(NO2)(H2O)2] · H2O (3a), [Cu2L2(NO2)(H2O)2] · H2O (3b), [Cu2L3(NO2)(H2O)2] · H2O (3c) and azido [Cu2L1(N3)(H2O)2] · H2O (4a), [Cu2L2(N3)(H2O)2] · H2O (4b) and [Cu2L3(N3)(H2O)2] · H2O (4c). The complexes were characterized by elemental analysis and by spectroscopy. They exhibit resolved copper hyperfine e.p.r. spectra at room temperature, indicating the presence of weak antiferromagnetic coupling between the copper atoms. The strength of the antiferromagnetic coupling lies in the order: NO2 N3 OH OAc. Cyclic voltammetry revealed the presence of two redox couples CuIICuII CuIICuI CuICuI. The conproportionality constant K con for the mixed valent CuIICuI species for all the complexes have been determined electrochemically.  相似文献   

6.
Summary A kinetic study of the regioselective homogeneous hydrogenation of quinoline (Q) to 1,2,3,4-tetrahydroquinoline (THQ) was carried out using the cationic complex [RuH(CO)(NCMe)2(PPh3)2]BF4 (1) as the precatalyst. The experimentally determined rate law wasr = {k 2 K 1/(1+K 1[H2])}[Ru0][H2]2, which becomesr = {k 2 K 1[Ru0]–[H2]2 at low hydrogen concentrations (k 2 K 1 = 28.5M –2 s–1 at 398 K). The corresponding activation parameters were found to be H = 42 + 6 kJ mol–1, S = – 115 ± 2JK–1mol–1 and G = 92 ± 8 kJ mol–1. Complex(1) was found to react with Q in CHCl3 under reflux to yield [RuH(CO)(NCMe)(N-Q)(PPh3)2]BF4 (2) which was also isolated from the hydrogenation runs. These experimental findings, together with the results ofab initio self-consistent-field molecular orbital calculations on the free organic molecules involved, are consistent with a mechanism involving a rapid and reversible partial hydrogenation of(2) to yield the corresponding dihydroquinoline (DHQ) species [RuH(CO)(NCMe)(DHQ)(PPh3)2]BF4 (4), followed by a rate-determining second hydrogenation of DHQ to yield [RuH(CO)(NCMe)(THQ)(PPh3)2]BF4 (3).  相似文献   

7.
The crystal structures of 2:1 inclusion complexes of gossypol with methyl propionate (GPMEP) and ethyl acetoacetate (GPEAA) have been determined by X-ray structure analysis. The crystals of GPMEP, C30H30O8l/2 C4H8O2, are monoclinic, space groupC2/c,a=11.079(3),b = 30.724(7), c = 16.515(5) Å, = 90.46(2)°,V = 5621(3) Å,Z = 8,D x = 1.33 g cm–3. The structure has been refined to the finalR value of 0.059 for 1899 observed reflections. The crystals of GPEAA, C30H30O8l/2 C6H10O3, are monoclinic, space groupC2/c,a=11.095(2),b=30.604(9),c = 16.955(5) Å, = 88.27(2)°,V = 5754(3) Å,Z = 8,D x = 1.35 g cm–3. The structure has been refined to the finalR value of 0.056 for 2502 observed reflections.In contrast to previously investigated inclusion complexes of gossypol the host molecules do not form centrosymmetric dimersvia hydrogen bonds. In the crystal structures the racemic gossypol is separated into enantiomers forming alternating bimolecular layers. Nearly perpendicular to these chiral bilayers run elongated cavities enclosed on each side by layers of opposite chirality. The surface of these layers is hydrophobic, the polar groups are hidden inside the layer. Guest molecules which are hydrogen bonded to the host are included in cylindrically shaped cavities. Possible hydrogen bonds between host and guest are analysed for this isostructural class of complexes.  相似文献   

8.
The CH4 molecule has been investigated ab initio, for four different distances RC? H and one distortion of a triangle HCH about the equilibrium condition, taking all 10 electrons into account, using the Allgemeines Programmsystem/SCF ? MO ? LC (LCGO ) Methode. The equilibrium distance RC? H was estimated to 2.053 a.u., the minimum of the total energy to ?40.06 a.u., the heat of formation to 17.0 eV and the ionization energy to 14.8 eV. For the breathing force constant and the force constant of the twisting vibration a ω1 of 3139 cm?1 and a ω2 of 1865 cm?1 were found.  相似文献   

9.
Summary Complexes of bidentate 3-amino-5-()-pyridyl-1,2,4-triazole (L1) and 3-amino-5-()-pyridyl-1, 2, 4-triazole (L2) of composition [ML1Cl2·H2O], [ML2Cl2·H2O], [ML 3 2/1 Cl2] and [ML 3 2/2 Cl2] [M=CoII, NiII, CuII, M=ZnII] have been prepared and characterized by elemental analyses, i.r., u.v./visible, e.s.r. spectra, magnetic moments and molar conductances.  相似文献   

10.
Paramagnetic copper(II) complexes with N-(3-hydroximino-2-methylbutan-2-yl)methylamine (HL), namely, Cu(HL)Cl2(I), Cu(HL)(SO4) · 2H2O (II), and Cu(HL)(NO3)2(III), were obtained. The crystal structures of I and II were determined. The blue crystals of these compounds are monoclinic. For I(C6H14Cl2CuN2O): a = 8.820(1) Å, b = 6.511(1) Å, c = 18.255(2) Å, = 92.86(1)° V = 1047.0(2) Å3, space group P21/c, calcd = 1.679 g/cm3, Z = 4 for R 1 = 0.0250; for II(C6H18CuN2O7S): a = 9.999(2) Å, b = 9.927(2) Å, c = 12.963(3) Å, = 106.37(3)°, V = 1234.5(4) Å3, space group P21/c, calcd = 1.753 g/cm3, Z = 4 for R 1 = 0.0324. Crystals of I have a molecular structure. The Cu coordination polyhedron is a square bipyramid (2N + 2Cl + Cl + Cl) due to additional contacts with two Cl atoms from the neighboring molecules. Structure II is built from polymeric chains. The environment of the Cu atom is a distorted cis-octahedron (2N + 2O(H2O) + 2O(SO4)). Complexes IIIIare characterized by IR and EPR spectroscopy.  相似文献   

11.
An ab initio SCF calculation of 42 points of the energy hypersurface of the fluoronium ion is presented using a contracted F(5s/3p), H(2s) gaussian basis set. In its equilibrium structure a bond length of 1.812 a.u. and a HFH bond angle of 127.2° are predicted. The calculated vibrational frequencies for H2F+, HDF+, and D2F+ are in good agreement with the experimental data.  相似文献   

12.
Complex compounds of divalent metal chlorides (CaCl2, NiCl2, MnCl2, CoCl2, CuCl2, CdCl2, PdCl2) are described, which had been obtained in a double complexation reaction in non aqueous media with nitro compounds and SbCl5:M II(CH3NO2) m (SbCl6)2 (m=4, 6),M II(C6H5NO2) m (SbCl6) (m=2, 3),M II(-C10H7NO2)2(SbCl6)2. Synthesis, analytical results and i.r. spectra are discussed.  相似文献   

13.
Crystals of (C2H5)4N+ CH3COOO · 4H2O crystallize in space groupP , witha=12.327(2),b=17.196(6),c=8.753(3) Å, =94.28(2), =91.09(2), =120.30(2)°, andZ=4. The structure was solved by direct methods and refined toR F -0.060 for 4803 MoK data. In the crystal structure, ordered (C2H5)4N+ cations are sandwiched between puckered layers of hydrogen-bonded water molecules and acetate anions. Each wateranion layer is constructed from an edge-sharing assembly of six independent, irregular, and non-planar polygons (two nonagons, two hexagons and two pentagons). All protons in the scheme of hydrogen bonding are uniquely located. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82036 (33 pages).Dedicated to Professor G. A. Jeffrey on the occasion of his retirement.  相似文献   

14.
Summary The syntheses of [Mo(5-C5H5)(3-C3H4R)(CO)(NO)]+ (R=H, 1- or 2-Me) and [Mo(5-C5H5)(3-C3H5)(NCR)(NO)]+ (R=Me or Ph), by treatment of Mo(5-C5H5)(CO)2(NO) with RC3H4Br and Ag+, and of Mo(5-C5H5)(3-C3H5)(NO)I with Ag+ in the presence of RCN, is described. Treatment of these cations with nucleophiles gives Mo(5-C5H5)(3-C3H5)(NO)X (X=halide, NCS or NCO), Mo(5-C5H5)(3-C3H5Q)(CO)(NO) (C3H5Q= propene ligand, Q= H, SCOMe, SEt, S2CNMe2, S2CNEt2, S2CN(Bu-n)2, C5H5, acac, OH, OMe or OAc), and [Mo(5-C5H5)(2C3H5L)(CO)(NO)]+ (L=PEt3, n-Bu3P, PPh3, PPh2H, PMe2Ph, C5H5N, 1-, 3- or 4-MeC5H4N and Me2NNH2). Reaction of [Mo(5-C5H5)(3-C3H5)(NCMe)(NO)+ with pyridine gave [Mo(5-C5H5)(3-C3H5)(pyr)(NO)]+, while treatment of [Mo(5-C5H5)(3-C3H5)(CO)(NO)]+ with PPh3 in the presence of NaOEt afforded Mo(5-C5H5)(CO)(NO)(PPh3). The1H and13C n.m.r. spectra of these complexes are discussed particularly in relation to the occurrence ofexo andendo isomers of the allylic species. Comparison is made briefly between Mo(5-C5H5)(3-C3H5)(NO)I and Mo(C5H5)2(NO)I.  相似文献   

15.
The1H and13C NMR spectra of two withasteroids isolated fromPhysalis ixocarpa Brot. have been studied in detail. Their spectral characteristics are discussed. A comparison of the results obtained has led to the identification of a withasteroid with the composition C28H40O8, mp 291–292°C (from methanol) as ixocarpalactone A, in spite of some difference in its physical constants. The other compound, with mp 252–253°C (from methanol), had the composition C28H40O6, [] D 20 +27±4°, is new and has been called ixocarpanolide. The structure of 5,20R-dihydroxy-1-oxo-6, 7-epoxy-22R-witha-2-enolide has been proposed for it.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 326–332, May–June, 1986.  相似文献   

16.
Summary A new ferrocene derivative, N-ferrocenylcarbonyl-N-benzoylhydrazine (H2FB) and its transition metal complexes, [M(FB)]2·H2O (M = MnII, CoII, CuII, ZnII, CdII or HgII) and M(HFB)2·nH2O (M = MnII or CdII) were prepared by reacting H2FB with the metal(II) acetates and characterized by elemental analyses, i.r. and u.v. spectroscopy and t.g.a. H2FB appears to act as a tetradentate ligand, coordinating to the metal through the nitrogen enolic oxygen atoms.  相似文献   

17.
Zusammenfassung Es wurde ein systematisches Studium des Systems im sauren Bereich durchgeführt. Aus den Ergebnissen der pH-Messungen wurden die Gleichgewichtskonstanten der Komplexe [YH3 T]2+, [YH2 T]+, [Y2H2 T]4+, [Y(H2 T)2] und HYT bestimmt. Es wurden die Verbindungen Y2(H2 T)3 · 8 H2O, Y2(H2 T)3 · 5 H2O und H[Y(H2 T)2] · 3 H2O isoliert. Diese wurden mit Hilfe von Röntgenstreuung, Thermoanalyse und IR-Absorptionsspektren untersucht.
A systematic investigation of the system in the acidic range was undertaken. The equilibrium constants of the complexes [YH3 T]2+, [YH2 T], [Y2H2 T]4+, [Y(H2 T)2] and HYT were determined, making use of the results of pH-measurements. The compounds Y2(H2 T)3 · 8 H2O, Y2(H2 T)3 · 5 H2O and H[Y(H2 T)2] · 3 H2O were isolated. Their X-ray diffraction, thermal analysis and IR spectra were investigated.


Mit 2 Abbildungen

Zugleich 24. Mitt. der Reihe: Koordinationsverbindungen von organischen Oxoubstanzen; H4 T=C4H6O6.  相似文献   

18.
The reactions of Cu2+, Co2+, and Ni2+ ions with N-phenyl-N-2-hydroxybenzyl- and N-phenyl-N-2-hydroxynaphthylmethyleneamine derivatives (HL n , n = 1–8) produced from the derivatives of aniline and aromatic -hydroxyaldehydes are studied. Among the ions studied, only Cu2+ forms stable complexes Cu(L n )2 · 2H2O. The structures of the synthesized compounds are studied by IR, UV, and EPR spectroscopies and differential thermal analysis. The magnetic moments of the Cu(L n )2 · 2H2O complexes are very small and range within 0.43–1.19 B, depending on the ligand structure, which indicates a strong antiferromagnetic interaction between the Cu2+ ions. The temperature dependence of the magnetic susceptibility measured for the Cu(L3)2 · 2H2O complex (where HL3 is N-4-methoxyphenyl-N-2-hydroxybenzylamine) is closest to the theoretical curve calculated for the binuclear Cu(II) complexes connected by the intermolecular exchange interaction. The Cu(II) complexes with HL n are shown to undergo oxidative dehydrogenation to form the corresponding metal salicyl-aldiminates. This reaction can occur on heating in the absence of oxygen and is accompanied by the Cu2+ Cu+ transition.  相似文献   

19.
Zusammenfassung Verbindungen des Typs R2NBCIN(Sime 3)2 * (R=C2H5,iC3H7, C6H11, C6H5) bleiben bis zu hohen Temperaturen beständig. Sie reagieren jedoch mit NaN(Sime 3)2 unter Übertragung einer Methylgruppe von einem Silicium-zu einem Boratom zu N,N-Bis(trimethylsilyl)-tetramethylcyclodisildiazan und R2NBmeN(Sime 3) (R=C2H5,iC3H7).
Compounds of the type R2NBClN(Sime 3)2 * were prepared. (R=C2H5,iC3H7, C6H11, C6H5. They do not show any tendency to condense thermally under elimination of trimethylchlorosilane. When these silylaminoboranes were allowed to react with NaN(Sime 3)2, complicated rearrangements were observed. The compounds in which R=C2H5 oriC3H7 rearranged under formation of N,N-bis(trimethylsilyl)-tetramethylcyclodisildiazane and R2NBmeN(Sime)2. In this reaction a migration of a methyl group from silicon to boron occurs.
  相似文献   

20.
Compounds of trigonal cluster chloroaqua complexes with cucurbit[8]uril were synthesized by slowly evaporating HCl solutions of chalcogenides heterometallic cubane cluster complexes of molybdenum and tungsten with cucurbit[8]uril in air; the complexes were characterized by X-ray diffraction analysis: (H3O)8[Mo3S4(H2O)2.5Cl6.5]2Cl(PdCl4)·(C48H48N32O16)· 29H2O (a = 13.3183(17) Å, b = 13.7104(18) Å, c = 18.225(3) Å; α = 80.263(3)°, β = 77. 958(3)°, γ = 87.149(4)°, V = 3207.4(7) Å3, space group P , Z = 1, ρ(calc) = 1.900 g/cm3), (H3O)4 [Mo3S4(H2O)3Cl6]2·(C48H48N32O16)3·68H2O (a = 21.413(6) Å, c = 49.832(10) Å; γ = 120°, V = 19788(8) Å3, space group R , Z = 3, ρ(calc) = 1.695 g/cm3), (H3O)6 [Mo3S4(H2O)3Cl6]2Cl2·(C48H48N32O16)·12H2O (a = 15.881(2) Å, b = 17.191(2) Å, c = 23.276(4) Å; β = 98.865(15)°, V = 6278.7(15) Å3, space group P21/c, Z = 2, ρ(calc) = 1.638 g/cm3), [W3S4(H2O)5Cl4]2·(C48H48N32O16)3·35H2O (a = 21.038(3) Å; α = 61.20(1)°, V = 6762.0(14) Å3, space group R , Z = 1, ρ(calc) = 1.582 g/cm3). The [Mo3S4(H2O)3Cl6]2− anion complex was isolated as three geometrical isomers.Original Russian Text Copyright © 2004 by E. V. Chubarova, D. G. Samsonenko, H. G. Platas, F. M. Dolgushin, A. V. Gerasimenko, M. N. Sokolov, Z. A. Starikova, M. Yu. Antipin, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1049–1058, November–December, 2004.  相似文献   

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