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1.
Conclusions Complexes with the composition AlHnCl3–nN(C2H5)3 (n=0, 1, 2, 3) were produced. The IR and PMR spectra of the complexes indicate that when hydrogen atoms are replaced by chlorine atoms, an increase is observed in the acceptor capacity of aluminum compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2171–2173, October, 1974.  相似文献   

2.
The molecular and electronic structures of closo-hexaboranes B6H6 2–, B6H7 , and B6H8 and closo-heterohexaboranes XYB4H4 (X = Y = CH, N; X = BH, Y = CH, N, NH, O) were studed by the ab initio (MP2(full)/6-311+G**) and density functional (B3LYP/6-311+G**) methods. The bridging H atoms in closo-hexaboranes B6H7 and B6H8 can undergo facile low-barrier migrations around the boron cage (the barrier heights are about 10—15 kcal mol–1). All heteroboranes having octahedron-like structures with hypercoordinated N and O atoms are rather stable and can be the subject of synthetic research efforts.  相似文献   

3.
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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4.
Summary The syntheses of dichlorobis(cycloalkylamine)platinum(II) complexes withcis andtrans cycloalkylamine ligands [cis-PtCl2(C3H5NH2)2 tocis-PtCl2(C8H15NH2)2 (3–8) andtrans-PtCl2(C7H13NH2)2 (9) andtrans-PtCl2(C8H15NH2)2 (10)] are described. The distinction betweencis andtrans isomers was achieved by1H-NMR spectroscopy. The antitumor activity was determined on the cell proliferation of the human MDA-MB-231 breast cancer cell line during long-term drug exposure. The complexes with small cycloalkylamine ligands (3–6) were inferior, those with large cycloalkylamine ligands were comparable (7) or superior (8) to cisplatin. Surprisingly, thecis/trans isomers7/9 and8/10 were equally active. All cycloalkylamine ligands were inactive. IR-spectroscopic studies showed that the size of the cycloalkylamine ring does not lead to significant differences in the Pt-Cl binding strength. Therefore it is assumed that the markedly stronger antitumor activity of the higher homologues,7–10, is not the result of a faster reaction with bionucleophils such as DNA. A possible explanation of the high activity of7–10 is the strong lipophilicity of the complexes. This assumption was confirmed by toxicity tests against confluent cultures.In memory of Professor Dr. Günter Gliemann, late director of the Institut für Physikalische und Theoretische Chemie, Universität Regensburg.  相似文献   

5.
Half-titanocene is well-known as an excellent catalyst for the preparation of SPS (syndiotactic polystyrene) when activated with methylaluminoxane (MAO). Dinuclear half-sandwich complexes of titanium bearing a xylene bridge, (TiCl2L)2{(μ-η5, η5-C5H4-ortho-(CH2–C6H4–CH2)C5H4}, (4 (L = Cl), 7 (L = O-2,6-iPr2C6H3)) and (TiCl2L)2{(μ-η5, η5-C5H4-meta-(CH2–C6H4–CH2)C5H4} (5 (L = Cl), 8(L = O-2,6-iPr2C6H3)), have been successfully synthesized and introduced for styrene polymerization. The catalysts were characterized by 1H- and 13C NMR, and elemental analysis. These catalysts were found to be effective in forming SPS in combination with MAO. The activities of the catalysts with rigid ortho- and meta-xylene bridges were higher than those of catalysts with flexible pentamethylene bridges. The catalytic activity of four dinuclear half-titanocenes increased in the order of 4 < 5 < 7 < 8. This result displays that the meta-xylene bridged catalyst is more active than the ortho-xylene bridged and that the aryloxo group at the titanium center is more effective at promoting catalyst activity compared to the chloride group at the titanium center. Temperature and ratio of [Al]:[Ti] had significant effects on catalytic activity. Polymerizations were conducted at three different temperatures (25, 40, and 70 °C) with variation in the [Al]:[Ti] ratio from 2000 to 4000. It was observed that activity of the catalysts increased with increasing temperature, as well as higher [Al]:[Ti]. Different xylene linkage patterns (ortho and meta) were recognized to be a principal factor leading to the characteristics of the dinuclear catalyst due to its different spatial arrangement, causing dissimilar intramolecular interactions between the two active sites.  相似文献   

6.
The (C10H10N2)0.5[SnF(SO4)] compound was synthesized via reaction of SnF2 with 4,4"-bipyridine (C10H8N2) in a diluted sulfuric acid solution (pH 3) and its X-ray diffraction analysis was carried out. The Sn2+ atoms coordinate one fluorine atom (Sn–F 2.062(2) Å) and two oxygen atoms of two sulfate groups (Sn–O 2.149(2) and 2.313(3) Å) thus forming the coordination polyhedron as a trigonal bipyramid with a stereochemically active unshared electron pair in its vertex. The sulfate groups act as bidentate bridges and join the neighboring Sn2+ complexes into infinite chains of [SnF(SO4)] n n anions combined in pairs through the Sn–F contacts (2.450(2) Å) to form ribbons whose voids contain two-charge 4,4"-bipyridinium cations.  相似文献   

7.
Summary The synergistic solvent extraction of Pr, Gd, and Yb with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one (HP) and tridodecylammonium (TDAHA), trioctylammonium (TOAHA), and dioctylammonium (DOAHA) salts (A =Cl, NO 3 , and ClO 4 ) in C6H6 has been studied. The composition of the extracted species has been determined asAmH+[LnP 4] (AmH+: ammonium salt cation). The values of the equilibrium constant have been calculated. The influence of the ammonium salt ions on the extraction process is discussed.
Synergetische Extraktion von Lanthaniden mit Mischungen aus 1-Phenyl-3-methyl-4-benzoyl-pyrazol-5-on und aliphatischen Aminen: Einfluß der Ammoniumsalzionen
Zusammenfassung Die synergetische Extraktion von Pr, Gd und Yb mit Mischungen aus 1-Phenyl-3-methyl-4-benzoyl-pyrazol-5-on (HP) und Tridodecylammonium-(TDAHA), Trioctylammonium-(TOAHA) und Dioctylammoniumsalzen (DOAHA) (A =Cl, NO 3 und ClO 4 ) in C6H6 wurde untersucht. Die Zusammensetzung der Extraktionskomplexverbindungen wurde zuAmH+[LnP 4] bestimmt; die Gleichgewichtskonstanten wurden berechnet. Der Einfluß der Ionen des Ammoniumsalzes auf die Extraktion wird diskutiert.
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8.
Zusammenfassung Die Chloraminierung von sekundären aliphatischen Aminen in Gegenwart von NH3 führt zu 2,2-Dialkyltriazaniumchloriden. Auf diese Weise konnte das schon bekannte 2,2-Dimethyl- und 2,2-Diäthyltriazaniumchlorid sowie die noch unbekannten Verbindungen [(C3H7)2N3H4]+Cl, [(C4H9)2N3H4]+Cl und das 2-Methyl-2-benzyltriazaniumchlorid aus den entsprechenden sekundären Aminen dargestellt werden.
Chloramination of secondary aliphatic amines
Chloramination of secondary aliphatic amines in the presence of ammonia yields 2.2-dialkyltriazanium chlorides. The known compounds [me 2N3H4]+Cl and [et 2N3H4]+Cl and the hitherto undescribed triazanium chlorides [pr 2N3H4]+Cl, [bu 2N3H4]+Cl, and 2-methyl-2-benzyltriazanium chloride have been synthesized by this method.
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9.
The paper presents a comparative analysis of the possibilities and characteristic features of the application of various polyhedral boron compounds, viz., the closo-decaborate anion [B10H10]2–, the closo-dodecaborate anion [B12H12]2–, the carba-closo-dodecaborate anion [CB11H12], carboranes C2B10H12, and the bis(dicarbollide) complexes [M(C2B9H11)2] (M = Fe, Co, or Ni), in boron neutron capture therapy (BNCT) for cancer. The requirements on compounds used in BNCT are formulated and the advantages of the application of the closo-dodecaborate anion are considered. The data on the synthesis of various derivatives of the closo-dodecaborate anion, which either already found use in BNCT or are most promising in this field, are summarized. The possibilities of the application of agents derived from the closo-dodecaborate anion in medical diagnostics are discussed.  相似文献   

10.
Titanium tert-butoxide (Ti(OC(CH3)3)4; Ti(O t Bu)4) was chemically modified with catechol (C6H4(OH)2) and hydrolysis and condensation behavior of a resultant modified alkoxide was studied. Spectroscopic results revealed that the reaction between titanium tert-butoxide and catechol resulted in the formation of catecholate groups (C6H4O2 2–) bound to titanium and corresponding release of tert-butanol. The mass spectrometry and cryoscopy indicated that main species was a dimer [(C6H4O2)2Ti2(O t Bu)4]. The hydrolysis of the modified alkoxide in the system with Ti:tetrahydrofuran (THF):H2O = 1:10:x (x = 0.5–10) resulted in the partial hydrolysis, and all the hydrolyzed products after the drying under reduced pressure were soluble in THF and chloroform.  相似文献   

11.
The electrical conductivity of several trialkylaluminum and alkyl-aluminum halides was investigated in dry benzene at 25°C. within the concentration range of 10?1–10?3M. The equivalent conductance of the trialkylaluminum systems decreased in the following order: Al(n-C6H13)3 > Al(n-C10H19)3 > Al(n-C4H9)3 > Al(i-C4H9)3 > Al(n-C3H7)3 > Al(C2H5)3. The conductance (1/R) of a given series was also examined and found to decrease as each alkyl group was successively replaced by a chlorine atom, thus: Al(C2H5)3 > Al(C2H5)2Cl > Al(C2H5)1.5Cl1.5 > Al(C2H5)Cl2 and Al(i-C4H9)3 > Al(i-C4H9)2Cl > Al(i-C4H9)Cl2. The ion pair dissociation constants K were calculated and show in a qualitative manner the difference between various organoaluminum systems. The relative rate of olefin polymerization was related to the conductivity of various organoaluminum–transition metal catalyst systems used. The effect of Lewis bases such as monoglyme, diglyme, triglyme, and tetraglyme on triethylaluminum indicated that the first-mentioned base forms a 1:1 type of complex as ordinary ethers do, whereas the remaining three bases utilize only two of their available oxygen atoms to coordinate with triethylaluminum. The effect of TiCl3 (in the presence of an ether) on the conductance was also determined.  相似文献   

12.
Excess molar volumes V E and excess molar heat capacities C P E at constant pressure have been measured, at 25°C, as a function of composition for the four binary liquid mixtures propylene carbonate (4-methyl-1,3-dioxolan-2-one, C4H6O3; PC) + benzene (C6H6;B), + toluene (C6H5CH3;T), + ethylbenzene (C6H5C2H5;EB), and + p-xylene (p-C6H4(CH3)2;p-X) using a vibrating-tube densimeter and a Picker flow microcalorimeter, respectively. All the excess volumes are negative and noticeably skewed towards the hydrocarbon side: V E (cm3-mol–1) at the minimum ranges from about –0.31 at x1=0.43 for {x1C4H6O3+x2p-C6H4(CH3)2}, to –0.45 at x1=0.40 for {x1C4H6O3+x2C6H5CH3}. For the systems (PC+T), (PC+EB) and (PC+p-X) the C P E s are all positive and even more skewed. For instance, for (PC+T) the maximum is at x 1,max =0.31 with C P,max E =1.91 J-K–1-mol–1. Most interestingly, C P E of {x1C4H6O3+x2C6H6} exhibits two maxima near the ends of the composition range and a minimum at x 1,min =0.71 with C P,min E =–0.23 J-K–1-mol–1. For this type of mixture, it is the first reported case of an M-shaped composition dependence of the excess molar heat capacity at constant pressure.Communicated at the Festsymposium celebrating Dr. Henry V. Kehiaian's 60th birthday, Clermont-Ferrand, France, 17–18 May 1990.  相似文献   

13.
Pulse radiolysis transient UV–visible absorption spectroscopy was used to study the UV–visible absorption spectrum (225–575 nm) of the phenyl radical, C6H5(), and kinetics of its reaction with NO. Phenyl radicals have a strong broad featureless absorption in the region of 225–340 nm. In the presence of NO phenyl radicals are converted into nitrosobenzene. The phenyl radical spectrum was measured relative to that of nitrosobenzene. Based upon σ(C6H5NO)270 nm=3.82×10−17 cm2 molecule−1 we derive an absorption cross-section for phenyl radicals at 250 nm, σ(C6H5())250 nm=(2.75±0.58)×10−17 cm2 molecule−1. At 295 K in 200–1000 mbar of Ar diluent k(C6H5()+NO)=(2.09±0.15)×10−11 cm3 molecule−1 s−1.  相似文献   

14.
The crystal structure of the paramagnetic bis(pyridine-2,6-dithiocarbomethylamide) nickel(II) nitrate (NiPDTA) is described: C18H22N6S4·(NO3)2·(H2O)1,5, monoclinic, C2/c,Z=4,a=14.705 (3) Å,b=23.254 (8) Å,c=8.383 (3) A, =98.18 (2)°,d x=1.55 gcm–3,d m=1.53 gcm–3. The structure was solved withPatterson and differenceFourier techniques and refined to a residual ofR=0.053. The nickel is surrounded by a square bipyramidal coordination of four thioamide sulfur atoms and two pyridine nitrogen atoms. Vibrational and electronic band positions for this compound are discussed.
Kristallstruktur und Spektren des Pyridin-2,6-dithiocarbomethylamid Nickel(II)-Komplexes
Zusammenfassung Die Kristallstruktur des paramagnetischen bis(Pyridin-2,6-dithiocarbomethylamid) Nickel(II)-nitrats (NiPDTA) wurde bestimmt. C18H22N6S4Ni·(NO3)2·(H2O)1,5, monoklin, C2/c,Z=4,a=14,705 (3) Å,b=23,254 (8) Å,c=8,383 (3) A, =98,18 (2)°,d x=1,55gcm–3,d m=1,53gcm–3. Das Phasenproblem wurde mittelsPatterson-und Differenz-Fourier-Synthese bestimmt und die Struktur bis zu einem kristallographischenR-Faktor vonR=0.053 verfeinert. Das Nickel-Atom ist von vier Thioamid-Schwefelatomen und zwei Pyridin-Stickstoffatomen in quadratisch-bipyramidaler Anordnung umgeben. Schwingungsspektren und Anregungsspektren des Komplexes werden diskutiert.
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15.
A number of polynuclear mixed carboxylates of nickel(II) with the general composition [Ni(OOCCH3)2–n (OOCR) n ] x (whereR=C13H27, C15H31, C17H35 and C21H43 andn=1 or 2) have been synthesized by the transacylation reactions of anhydrous nickel acetate with higher carboxylic acids in refluxing toluene. On recrystallization from benzene-alcohol mixtures, mono-alcoholate complexes, Ni(OOCCH3)2–n (OOCR) n ·ROH (whereR=CH3 and C2H5) have been isolated. All these derivatives have been characterized by the molecular weight determinations, infra-red and electronic reflectance spectra and magnetic susceptibility measurements.
Synthese und Eigenschaften einiger gemischter Carboxylat-Komplexe von Nickel(II)
Zusammenfassung Komplexe des Typs [Ni(OOCCH3)2–n (OOCR) n ] x (mitR=C13H27, C15H31, C17H35 und C21H43,n=1 oder 2) wurden aus wasserfreiem Nickelacetat mit höheren Carbonsäuren in siedendem Toluol erhalten. Bei der Kristallisation aus Benzol-Alkohol-Mischungen wurden Monoalkoholate Ni(OOCCH3)2–n (OOCR) n ·ROH (mitR=CH3 und C2H5) isoliert. Die Charakterisierung der Komplexe erfolgte mittels Molekulargewichtsbestimmung, Infrarot- und Elektronenspektren und der Messung der magnetischen Susceptibilität.
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16.
From the reaction between W2Cl6(PEt3)2 and H2O in tetrahydrofuran the dark green crystalline compound [Et3PH][W4O3Cl7(PEt3)3] was obtained and characterized by X-ray crystallography. At –155° the cell dimensions werea=b=c=20.392(3) Å,Z=8,d calcd=2.36 g cm–3 in the space group I23. The compound is a triethylphosphonium salt of the [W4O3Cl7(PEt3)3] anion. The latter contains a tetrahedron of tungsten atoms with W–W=2.61 Å (ave) and may be viewed as a W3(-Cl)3Cl3(PEt3)3 cluster capped by ad 0-[WO3Cl] unit and this has proved useful in examining the bonding within the cluster by use of the M.O. calculational method of Fenske and Hall. The cluster anion has crystallographically imposed C3v symmetry. Theoxo-groups bridge the tungsten atoms in a notably asymmetric manner W–O=1.87(2) Å and 2.04(2) Å with the shorter distances being involved with the capping [WO3Cl] unit. The W–P bonds lie in the W3(3-Cl)3 plane and the three terminal W–Cl bonds are trans to theoxo-bridges.  相似文献   

17.
The chlorohydrination of allyl chloride with chlorine in water was studied at 20–80°C. The effect of the concentration of chloride ions within the range 0–3.6 mol/l on the selectivity of formation of glycerol dichlorohydrins was studied. An equation that relates the selectivity and the concentration of Clwas derived, which adequately describes experimental data. The schemes of parallel and consecutive reactions occurring in the system were suggested. The ratios between the rate constants of the following reactions were found: the reactions of chlorine with water and allyl chloride dissolved in water (k 1/k 4= 4.1 × 10–4), the reaction of allyl chloride with hypochlorous acid and the decomposition of hypochlorous acid (k 2/k 3= 1.7 × 103), and the reactions of the allyl chloride–chlorine complex with a water molecule and Cl(k 5/k 6= 2.9 × 10–2).  相似文献   

18.
Summary Solid complexes of 3-acetyl-1,5-diaryl and 3-cyano-1,5-diaryl formazans were prepared and characterized by elemental analysis, IR, NMR, TGA and DTA analyses. Based on these studies, the suggested general formula for the complexes is [M(HL) m (OH) n or (NO 3 or Cl) x ·(H2O) y or (C2H5OH orDMSO) z , where HL=formazanM=Ce3+, Th4+, and UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 andz=0–3. The metal ions are expected to have coordination numbers 6–8.
Strukturuntersuchungen an 3-Acetyl-1,5-diaryl- und 3-Cyan-1,5-diaryl-formazan-Chelaten mit Cer(III), Thorium(IV) und Uran(VI)
Zusammenfassung Die hergestellten Chelate wurden mittels Elementaranalyse, IR, NMR, TGA und DTA charakterisiert. Darauf basierend wird die generelle Formel [M(HL) m (OH) n bzw. (NO 3 oder Cl) x ·(H2O) y oder (C2H5OH bzw.DMSO) z ] vorgeschlagen, wobei HL=Formazan,M=Ce3+, Th4+ oder UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 undz=0–3. Die Metallionen haben Koordinationszahlen von 6–8.
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19.
The acetone adduct of trirhenium nonachloride, Re3Cl9 (acet)3, where acet=acetone, reacts in acetone solution at room temperature with tetrabutylammonium chalcogenides [N(C4H9)4]2E, where E=S, Se and Te, producing the tetrabutylammonium salts of the new cluster anions [Re3 (μ3-E) (μ2-Cl)3Cl6]2−. In the crystallographically determined structures of these compounds, triangles of rhenium atoms are capped by single chalcogen atoms, giving anions of near C3v symmetry. The compound where E=S is also formed in the reaction of Re3Cl9 with [N(C4H9)4]2 [MoS4] by sulfide transfer.  相似文献   

20.
Interaction of R n M-derivatives of 4-nitrophenol and thiophenol (R n M= PhHG, PPh3Au, Ph3Sn, Ph4Sb) with a set of inorganic and organic anions (Cl, Br, I, CN, [PhOCO], [4-NO2C6H4OCO]) was studied by IR and electronic spectroscopy in solvents with different polarities and coordinating properties (C6H6, CH2Cl2, DMSO). The dependence of the character of the interaction with the anions on the nature of the metal atom and heteroatom, the type of anions and the nature of the media was analyzed. Such interaction leads to ion-molecular complexes, and also to dissociation of the X-M bond (X = O, S, M = Au, Hg. Sb) with formation of the (4-NO2C6H4X) anion even in weakly polar media. Only in the case of 4-NO2C6H4OSnPh3 does the reaction stop at the stage of complex formation. In other cases the role of complex formation with anions is less than with neutral coordinating reagents.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1838–1841, July, 1996.  相似文献   

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