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1.
In the presence ofEt 3N·PF5, F4P(CH3N)2PF2NHNH+(CH3)2 (I) looses one molecule of HF to yield F3P(CH3N)2PF2NHN(CH3)2 (II). The reaction ofI withDABCO (1,4-diazabicyclo[2.2.2]octane) yieldsDABCO·2H++(CH3NPF4) 2 –– (III) and [CH3NPF2NHN(CH3)2]2 (IV). Even in the presence of CsF,II does not react with HF.
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2.
The polymethylhydrosiloxane (PMHS) modified by bifunctional organic compounds (diamines), offer the possibility of producing organic-inorganic hybrid materials. These materials present excellent opto-electronic properties and find numerous applications such as the manufacture of electroluminescent diodes and ion or radiation sensors.This work shows that monolithic and transparent hybrid gels were obtained by reaction at room temperature of PMHS with diamines in tetrahydrofuran, using hexachloroplatinic acid (H2PtCl6·6H2O) as catalyst. The products have been characterized by infrared and 29Si MAS-NMR spectroscopy. The results show that the diamines have reacted with the PMHS leading to the monolithic and transparent gels in which both organic-inorganic —Si—(H)N—(CH2) n —N(H)—Si— bridges are formed (n = 3, 4 and 6). The thermal analysis of the xerogels was determined by TGA and DTA. The structure and texture of the obtained materials, were studied by Chemical Analysis and the Brunauer-Emmett-Teller (BET) method.  相似文献   

3.
Summary New complex salts of lanthanide chlorides with hexamethylenetramine of the general formulaLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA-hexamethylenetetramine N4(CH2)6;n=8, 10, 12] have been obtained. On the basis of IR IR spectra (4000-200cm–1) and Raman spectra (3000-300 cm–1), changes in the coordination sphere structure of the salts occurring in the course of thermal dehydration have been determined.
Darstellung und Untersuchung der Eigenschaften von Komplexsalzen der Lanthanidchloride mit Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthanidchloride mit Hexamethylentetramin mit der allgemeinen FormelLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA — Hexamethylentetramin N4(CH2)6;n=8, 10, 12] wurden dargestellt. Die Änderungen in der Struktur der Koordinationssphäre während der thermischen Dehydration der Salze wurden mittels Infrarot-(4 000–200 cm–1) und Ramanspektroskopie (3 000–300 cm) bestimmt.
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4.
Summary New complex salts of lanthanide thiocyanates with hexamethylenetetramine of the general formulaLn(NCS)3·2[N4(CH2)6·nH2O, whereLn=La,Pr,Nd,Sm,Gd,Dy,Er andn=0–10, have been analyzed. IR spectra have been obtained in the range of 200–4000 cm–1, frequencies of vibrations of low and high hydration state compounds have been analyzed, and differences between the structures of the coordination speheres of these salts are demonstrated. Diffractometric examinations and measurements of the magnetic susceptibility of several salts have been performed.
Synthese und spektroskopische, diffraktometrische und magnetische Untersuchungen von Verbindungen der Lanthaniden mit Rhodanid und Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthaniden mit Rhodanid und Hexamethylentetramin mit der allgemeinen FormelLn(NCS)3·2[N4(CH2)6nH2O (Ln=La,Pr,Nd,Sm,Gd,Dy,Er;n=0–10) wurden untersucht. Die IR-Spektren der Verbindungen im Bereich von 200–4000 cm–1 wurden aufgenommen. Die Schwingungsfrequenzen hoch- und niederhydrierter Verbindungen wurden analysiert und die Unterschiede in der Struktur der Koordinationssphäre bestimmt. An einigen Komplexen wurden diffraktometrische Untersuchungen und Messungen der magnetischen Suzaptibilität durchgeführt.
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5.
The N—H and O—H bond dissociation energies in 4-hydroxydiphenylamine Ph—NH—C6H4—OH (D NH= 353.4, D OH=339.3 kJ mol–1) and its semiquinone radicals D NH(Ph—NH—C6H4—O·) = 273.6, D OH(Ph—N·—C6H4—OH) = 259.5 kJ mol–1 were first estimated using the parabolic model and experimental data (rate constants) on two elementary reactions with participation of N-phenyl-1,4-benzoquinonemonoimine (2). One of the reactions, namely, that of 2 with aromatic amines, was studied in this work using a specially developed method.  相似文献   

6.
The complexes of the type M(HDMBG)2(CH3COO)2·nH2O ((1) M:Mn, n=1.5; (2) M:Ni, n=0; (3) M:Cu, n=2; (4) M:Zn, n=2; DMBG: N,N-dimethylbiguanide) present in vitro antimicrobial activity. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamics effects that accompany them. The different nature of the ligands generates a different thermal behaviour for the complexes. The thermal transformations are complex processes according to TG and DTG curves including dehydration, oxidative condensation of –C=N– units as well as thermolysis processes. The final products of decomposition are the most stable metal oxides.  相似文献   

7.
In this study, Lnx(SiO4)6O(1.5x–12) (Ln: Nd, La) materials as electrolytes for solid oxide fuel cells (SOFC) were prepared by the sol-gel process. It has been reported that the apatite structure of Lnx(SiO4)6O(1.5x–12) shows higher ionic conductivity than yttrium-stabilized zirconium oxide at the working temperature of the SOFC. Ln10(SiO4)6O3 is a major component of the Lnx(SiO4)6O(1.5x–12) system. Ln10(SiO4)6O3 consists of Ln9.33(SiO4)6O2 and a small amount of Ln2SiO5. It has been proposed that the ionic conductivity of Lnx(SiO4)6O(1.5x–12) decreases with increasing Ln2SiO5 with non-apatite structure. The object of the present study was to bring about this decrease by generating Ln2SiO5 in the system.Precursor solutions for synthesis of the powder were prepared using tetraethoxysilane (Si(OC2H5)4) and neodymium acetate monohydrate (Nd(CH3COO)3·H2O) or lanthanum acetate monohydrate (La (CH3COO)3·H2O) as raw materials and acetic acid (CH3COOH), 2-methoxyethanol (C2H5OCH2CH2OH), and triethanolamine (N(CH2CH2OH)3) as solvents. To obtain the powder, the solution was dried and heat-treated at 600 °C for 2 h. Disks made from the powder were heat-treated at temperatures between 1100 and 1500 °C for 10 h. The results of an XRD investigation indicate that almost all diffraction peaks of these samples could be assigned to Ln9.33(SiO4)6O2. The sample with x = 10.00 included a small amount of Ln2SiO5. The ionic conductivity of this latter sample was higher than that of other samples with similar values of x (x = 9.33 and 10.67).  相似文献   

8.
Thermal transformations (at 340 to 390 °C) of coprecipitates of iron and cobalt acrylates, [Fe3O(CH2CHCOO)6OH][Co(CH2CHCOO)2]2.4 (1) and [Fe3O(CH2CHCOO)6OH][Co(CH2CHCOO)2]1.5·3H2O (2), are studied. The dependence of the degree of gas evolution () on time is described by the equation () wherek 1=2.3 · 1012 · exp[–49500/(RT)] s–1,k 2=6.0 · 106 · exp[–33000/(RT)] s–1 andk 1=2.6 · 1012 · exp[–49000/(RT)] s–1,k 2=6.6 · 105 · exp[–30000/(RT)] s–1 for cocrystallizates1 and2, respectively. The coefficient 1 decreases as the temperature increases. The value of 1 for compound1 is higher than that for compound2. The composition of products of the transformations of1 and2 are studied. The main solid state products of the decomposition are nanometer-sized particles of cobalt ferrite, CoFe2O4, with a narrow size distribution stabilized by the polymeric matrix. The thermal transformations of cocrystallizates1 and2 include dehydration, thermal decomposition, copolymerization in the solid state, and decarboxylation of the metallocarboxylate groups of the polymer. The effect of the ratio between the Fe clusters and the Co-containing fragments on the process of thermal transformation is analyzed.For Part 40, seeRuss. Chem. Bull., 1994,43, 2020.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 885–893, May, 1995.The authors are grateful to A. N. Titkov for optical microscopic and electron microscopic studies.  相似文献   

9.
Three crystalline complexes of sodium perchlorate with different flexible double betaines [Na 2(L1)(ClO4)(H2O) n ](ClO4) n (1), [Na 3(L2)(ClO4)3(H2O)2 n ] (2), and [Na(L 3)(CH3OH)n]-(ClO4) n ·xnH2O (x=0.25) (3) [O2CCH2N+Me2–(CH2) n -N+Me2CH2CO2 ,n=2 L1;n=3 L2;n=4 L3] have been synthesized and characterized by single-crystal X-ray structure analysis. Complex (1) comprises tetranuclear sodium units consolidated by betaine and aqua ligands, which are bridged by half of the ClO4 anions to form layers matching the (200) planes, the remaining uncoordinated ClO4 anions being accommodated between adjacent layers. Complex (2) possesses a double-layer polymeric structure with the sodium atoms bridged by ligand oxygen atoms to form columns running parallel to thea axis, which are interconnected by double-betaine ligands lying parallel to theac plane. All of the ClO4 groups and water molecules are coordinated to the metal atoms. In complex (3) the chains composed of alternating eight-membered and four-membered metallocycles are cross-linked by the betaine ligands, which lie in the (020) and (01/1) families of planes, to yield a three-dimensional network. All of the ClO4 groups and water molcules fill the resulting infinite channels running parallel to thea axis. Two unusual carboxylate coordination modes are identified, namely 3-O andhapto-3-O plushapto-2-O in (1) and (2), respectively.  相似文献   

10.
The clusters, (-H)3Ru3( 3-CY)(CO)9–n (PPh3) n [Y=–CH2CHCH2, n=0 (1); Y=–CH2CHCH2, n=3 (2); Y=–C6H4CH3, n=0 (3); Y=–C6H4CH3, n=3 (4)], have been synthesized in good yields and characterized by IR and NMR spectroscopy and by elemental analysis. The electrochemical properties of these clusters is also reported. These data indicate that the -system of the apical substituent does not interact significantly with the cluster and should be available for further chemistry.  相似文献   

11.
29Si NMR peaks due to species with the double four-membered ring siloxane backbone composed of both Si(O)4/2 and CH3Si(O)3/2 units, (CH3) n Si8O 20 – n /(8 – n) – (n=1–3), formed by co-hydrolysis of tetraethoxysilane and methyltriethoxysilane in the presence of tetramethylammonium ions in methanol have been assigned. It has been found that 29Si NMR peaks due to Si(OSi)3(O) units shift to lower frequencies by replacement of the adjacent Si(O)4/2 units by CH3Si(O)3/2 units, in other words, with increasing m value in Si[OSi(O)3]3 – m [OSi(CH3) (O)2] m (O) (m=0–2). Peaks from CH3 Si(OSi)3 units in the species have also appeared as separated due to the kind of neighbor structural units. On the basis of the assignments, positions of CH3Si(O)3/2 units in the cubic octameric siloxane framework of (CH3) n Si8O 20 – n /(8 – n) – (n=2, 3), for both of which three isomers are present, have been estimated.  相似文献   

12.
Organosilicon gels [Co(NH2R2)2Cl2] and [Cr(NH2R2)3Cl3], containing a diaminodichloride complex of cobalt(II) and triaminotrichloride complex of chromium(III) (R2 = CH2CH2CH2SiO(OEt)), were synthesized by the hydrolysis of complexes [Co(NH2R1)2Cl2] (I) and [Cr(NH2R1)3Cl3] (II) incorporating peripheral triethoxysilyl groups (R1 = CH2CH2CH2Si(OEt)3). The coprecipitated [Co(NH2R2)2Cl2] · 4NH2R3, [Cr(NH2R2)3Cl3] · 6NH2R3, [Co(NH2R2)2Cl2] · 2SiO2, and [Cr(NH2R2)3Cl3] ·xSiO2 · (3 – x)SiHO1.5 (R3 = CH2CH2CH2SiO1.5) gels were obtained by cohydrolysis of complexes I and II with 3-aminopropyltriethoxysilane or triethoxysilane. Interaction with SiH(OEt)3 is accompanied by the decomposition of silicon hydride groups and the formation of tetraethoxysilane derivatives. The heating of dry gels in a flow of argon or oxygen to 600° results in the formation of amorphous silica having a specific surface area 2–467 m2/g and containing crystalline metals, their chlorides, oxides, silicates, or carbides.  相似文献   

13.
Copper(II) complexes with (1R*,4S*)-1-N-morpholino-n-menth-8-en-4-one (HL), namely, [Cu2(HL)2Cl4] (I) and [Cu2(HL)LCl3] · CH3CN (II), were synthesized and characterized by X-ray diffraction analysis, magnetic susceptibility, and EPR methods. The complexes have binuclear structures. In compound I, the coordination polyhedron of CuCl3N2 is a square pyramid in planar Cu2Cl2 metal cycle; the exchange couplings of unpaired electrons of Cu(II) ions are weak. Complex II incorporates polyhedra of CuCl2N2 (flattened tetrahedron) and of CuCl2N2O (trigonal bipyramid). The Cu2ClNO metal cycle is nonplanar with antiferromagnetic exchange coupling and exchange parameter –2J = 182 cm–1. The EPR spectrum of compound I are analyzed.  相似文献   

14.
New inclusion complexes (n-C3H7)4N+C6H5CO 2 · 3(NH2)2CS (1), (n-C4H9)4N+[(C6H5CO2)2H]·6(NH2)2CS (2) and (C2H5)4N+C6H5CO 2 ·(NH2)2CS (3) have been prepared and characterized by X-ray crystallography. Crystal data, MoK radiation: 1, space group P212121, Z = 4, a = 8.544(3), b = 14.588(4), c = 24.448(4) Å, and R1 = 0.062 for 1536 observed data; 2, space group Pbcn, Z = 4, a = 24.938(3), b = 8.911(1), c = 23.733(9) Å, and R1 = 0.055 for 2132 observed data; 3, space group P212121, Z = 4, a = 9.996(2), b = 10.122(4), c = 18.350(2) Å, and R1 = 0.049 for 1180 observed data. In the crystal structure of 1, the (n-C3H7)4N+ cations are stacked in a single column and accommodated within each channel built up by wide thiourea ribbons and benzoate ions via N—H···O hydrogen bonds. In the crystal structure of 2, the tetrabutylammonium cations are arranged in a zigzag column within each channel built of parallel corrugated thiourea layers that are inter-linked by dimeric [(C6H5CO2)2H] groups through N—H·O hydrogen bonds. In compound 3 the (C2H5)4N+ cations are accommodated in pseudo-channels generated from infinitely extended thiourea-benzoate composite ribbons.  相似文献   

15.
Densities of aqueous solutions of a series of polymethonium chloride and bromide salts (CH3)3–N–(CH2)n–N–(CH3)3X2 have been measured at 25°C. Apparent molal volumes have been calculated, and methylene-group contributions to the limiting apparent molal volumes °v have been estimated. Constant values of the methylene-group contribution of 16.5 and 17.0 cm3-mole–1 were obtained for the bromide and chloride salts, respectively. These values are consistent with methylene-group contributions reported for other series of organic electrolytes.  相似文献   

16.
Two new phenol based macroacyclic Schiff base ligands, 2,6-bis({N-[2-(phenylselenato)ethyl]}benzimidoyl)-4-methylphenol (bpebmpH, 1) and 2,6-bis({N-[3-(phenylselenato)propyl]}benzimidoyl)-4-methylphenol (bppbmpH, 2) of the Se2N2O type have been prepared by the condensation of 4-methyl-2,6-dibenzoylphenol (mdbpH) with the appropriate (for specific reactions) phenylselenato(alkyl)amine. These ligands with Cu(II) acetate monohydrate in a 2:1 molar ratio in methanol form complexes of the composition [(C6H2(O)(CH3){(C6H5)CN(CH2)nSe(C6H5)}{(C6H5)CO}2Cu] (3 (n = 2), 4 (n = 3)) with the loss of phenylselenato(alkyl)amine and acetic acid. In both these complexes, one arm of the ligand molecule undergoes hydrolysis, and links with Cu(II) in a bidentate (NO) fashion, as confirmed by single crystal X-ray crystallography of complex 3. The selenium atoms do not form part of the copper(II) distorted square planar coordination sphere which has a trans-CuN2O2 core. The average Cu–N and Cu–O distances are, respectively, 1.973(3) and 1.898(2) Å. The N–Cu–N and O–Cu–O angles are, respectively, 167.4(11)° and 164.5(12)°. The compounds 1–4 have been characterized by elemental analysis, conductivity measurements, mass spectrometry, IR, electronic, 1H and 77Se{1H} NMR spectroscopy and cyclic voltammetry. The interaction of complex 3 with calf thymus DNA has been investigated by a spectrophotometric method and cyclic voltammetry.  相似文献   

17.
The intersecting parabolas model is used to analyze experimental data for the following radical cyclization and decyclization reactions: RCH=CH(CH2)nN·R1 cyclo-[NR1CH(CH2)n]C·HR,R(CH2)2OOCH2C·HR cyclo-[RCHOCH2] + RCH2CH2O·, cyclo-[(CH2)nOOCHC· HR] cyclo-[RCHOCH](CH2)nO·, cyclo-[(CH2)nOC·RO] RC(O)O(CH2) n–1C·H2, and cyclo-[(CH2)nCHO·] CH(O)(CH2) n–1C·H2. The activation energy of the thermally neutral reaction (E e,0) is calculated for each class of reactions. E e,0 depends on the electronegativity of the heteroatom Y of the reaction center C C...Y, the force constants of the reacting bonds, and the strain energy of the ring formed. For the cyclization and decyclization of six-membered rings, the empirical relationship between the elongation of the reacting bonds in the transition state (r e) and the difference in electronegativity (EA) between the C and Y atoms (Y = C, N, O) has the form r e ×1011, m = 3.83 – 0.0198(EA, kJ/mol).Translated from Kinetika i Kataliz, Vol. 46, No. 1, 2005, pp. 5–13.Original Russian Text Copyright © 2005 by Denisova, Denisov.  相似文献   

18.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

19.
Silver (I) complexes [Ag2(tptz)(dppm)2(DMF)](BF4)2·2DMF (1), [Ag(tptz)(dppe)]n(BF4)n·2nH2nMeOH (2), [Ag2(tptz)2(dppp)2](BF4)2 (3) and [Ag2(tptz)2(dppb)](BF4)2 (4) were obtained from the reactions of AgBF4 and diphosphine Ph2P(CH2) nPPh2 (Lpp, n=1–4) in the presence of 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) in MeOH–DMF. Single crystal analyses showed that the closed metallocyclic unit [Ag2(Lpp)2]2+ with double Lpp bridges was obtained in (1) and (3) with an odd number of n, while an open metallochain (Ag2Lpp)2+ with a single bridge formed in (2) and (4) with n being even. Coordination modes for the diphosphines are directly related to the rigid tptz ligand with a large -system.  相似文献   

20.
Three mercury(II) complexes containing double-betaine and halide ligands, [(HgCl2)2(L1)] n (1), [(HgBr2)2(L1)(H2O)2] n (2), and [2HgCl2(HL1)·Hg2Cl6] n (3) [L1=O2CCH2N+(CH2CH2)3-N+H2CO2 ], have been prepared and shown to have polymeric structures by single-crystal X-ray analysis. Complex (1) exhibits an infinite zigzag chain in which each mercury(II) atom is coordinated by pairs of carboxylate oxygen atoms and chloride ligands in a distorted tetrahedral geometry. In complex (2), the mercury(II) atom is in an unusual square-planar coordination geometry, and weak mercury-ligand and hydrogen bonding extend the structural skeletons into a three-dimensional network. Complex (3) consists primarily of an assembly of HgCl2(HL1) moieties and [Hg2Cl6] anions, and the mercury(II) atoms are in planar T-shaped and distorted tetrahedral coordination environments, respectively. The resulting three-dimensional network is based on the cross-linkage of nearly planar, wide ribbons running in thea direction.  相似文献   

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